Meditations on First Philosophy





Translated by Ian Johnston
Vancouver Island University
Nanaimo, BC, Canada



This translation is based upon the first Latin edition of Descartes’ Mediations (1641), omitting the Objections and Replies included in that text. I have incorporated most of the relatively few corrections made to that text in the second Latin edition (1642), none of which is particularly important, other than the title page. I have also inserted a number of additions made to the Latin text in the first French edition (1647), which was supervised by Descartes, who approved of the result. These additions from the French edition, which are indicated by square brackets, are inserted here only where they help to clarify the meaning of the original Latin. Other changes in the French text I have ignored.

I have provided some endnotes for the reader who might require assistance with Descartes’ argument. These are not intended to provide a through or satisfactory commentary, but merely occasional guidance.

Students, teachers, and members of the general public may download and distribute this text without permission and without charge. They may also freely edit the text to suit their purposes. All commercial use without the permission of the translator is, however, prohibited. Please contact Ian Johnston for details.

This translation was posted on the web in 2012. A published book of this translation (2013) is available from Broadview Press.

An RTF format of this translation (compatible with Word and Open Office) is available at the following site: Meditations [RTF]















To the very learned and most illustrious
Dean and Doctors
of the Sacred Faculty of Theology
in Paris

The reason urging me to offer you this treatise is compelling, and I believe that, once you understand the organizing principle of what I have undertaken, you will have an equally just reason for taking the work under your protection. Such is my confidence, in fact, that I can find no better way of recommending it to you than by outlining briefly what I set out to do in it.

Of those questions which ought to be resolved with the help of philosophy rather than of theology, I have always thought that the two most important concerned God and the soul. For although among those of us who believe, faith is sufficient to accept that the human soul does not perish with the body and that God exists, it really does not seem at all possible to convince non-believers about any religion and perhaps about any moral virtue, as well, unless one first establishes the truth of those two questions for them by natural reason. And since this life frequently offers greater rewards for vice than for virtue, few people would prefer what is right to what is convenient, if they did not fear God and were not anticipating a life hereafter. It is indubitably true that we must believe in the existence of God, because that is what we are taught by the Holy Scriptures, and that, on the other hand, we must believe the Holy Scriptures because they come from God, for since faith is a gift from God, obviously the same Being who gives us grace to believe other things can also give us grace to believe in His own existence. However, we cannot make this argument to non-believers, for they would claim that such reasoning is circular. And, indeed, I have observed not only that all of you, as well as other theologians, affirm that the existence of God can be proved by natural reason, but also that it can be inferred from sacred Scripture, that we can acquire knowledge of Him [much] more readily than of many created things, and that, in fact, it is so utterly easy that those who lack such knowledge are themselves to blame, as we can see from these words in Wisdom 13: And these men ought not to be forgiven, for if they could know so much that they were able to assess the things of this world, why did they not find the Lord of these things more easily? And Romans, Chapter 1, states that such men have no excuse. And, once again, in the same place, the following words What is known of God is manifest in them appear to be advising us that everything which can be known about God can be revealed by reasons we do not derive from anywhere other than our own minds. Thus, I did not think it would be inappropriate for me to explore how that might be done and by what road God might be known more easily and more certainly than worldly matters.

As far as the soul is concerned, many people have judged that its nature cannot be investigated easily, and some have even dared to claim that human reasoning has convinced them that the soul dies at the same time as the body and that faith alone can maintain the opposite. However, since the Lateran Council, in its eighth session, held under Pope Leo X, condemns those who make such claims and expressly commands Christian philosophers to refute their arguments and to use their full abilities to demonstrate the truth, I have not hesitated to take on this task as well.(3)

Furthermore, I know that several impious people are unwilling to believe that God exists and that the human mind is distinct from the body, for no other reason than, as they allege, no one has been able to prove the truth of these two claims up to now. I in no way agree with these people but, by contrast, believe that almost all [the reasons] great men have brought forward in support of these two questions, once they are sufficiently understood, have the force of demonstrations, and I am convinced that it is virtually impossible to offer any arguments that have not been previously set out by other people. Nevertheless, I consider that there can be no more useful task facing philosophy than to seek out diligently, once and for all, the best of all these arguments and to set them down so accurately and clearly that everyone from now on will accept them as sure proofs. Finally, since I was urgently requested to carry out this work by several people who knew that I had cultivated a certain method for resolving some difficulties in the sciences—not a new method, to be sure, because there is nothing more ancient than the truth, but one which they had often seen me use, and not without success, in other areas—I thought it was my duty to make some sort of attempt at it in this matter.

Whatever I have been able to offer is all contained in this treatise. Not that I have tried to gather together here all the various arguments which one could adduce to serve as demonstrations of the same points, for this did not seem to be worth the effort, except where there was no one proof which was sufficiently certain. Instead, I have described in detail only the first and most important ones in such a way that I now venture to publish them as very certain and very clear demonstrations. Furthermore, I will add that these proofs are also such that I do not believe there is any road open to the human mind by which it is possible for people ever to come up with better ones. For the urgency of the subject and the glory of God, to which everything here relates, compel me to speak here of my own work somewhat more freely than I usually do. However, although I believe these arguments are clear and certain, that still does not convince me that they are well suited to everyone’s understanding. In geometry there are many works written by Archimedes, Apollonius, Pappus, and others that everyone has accepted on the basis of their clarity and certainty, because, in fact, their arguments contain nothing which, examined in and of itself, is not very easy to understand and because none of the stages lacks an accurate and coherent link with what has gone before.(4) Nevertheless, because these works are rather long and demand an assiduously attentive reader, they are understood by relatively few people. And so, although I believe that the clarity and certainty of the demonstrations I use here are equal to, or even better than, those in geometric [proofs], I still fear that there are not many people who can grasp them sufficiently, partly because they, too, are somewhat long and some depend on others, and, most importantly, because they demand a mind that is entirely free of prejudice and that can easily detach itself from its association with the senses. Besides, we will certainly not find more people in the world well equipped for metaphysics than for geometry. However, there is an additional difference. In geometry, everyone is convinced that, as a rule, nothing is written down which has not been clearly proven, and so unskilled readers more frequently make the mistake of approving what is false, because they wish to look as if they understand it, than of refuting what is true. But in philosophy, by contrast, people believe that there is nothing which cannot be disputed on one side or the other, and therefore few of them investigate the truth, while the vast majority, eager to acquire a reputation for genius, boldly assail the most important truths.

Hence, because my arguments, whatever their quality, are exploring philosophical issues, I do not expect to achieve very much with them, unless you assist me with your patronage and protection. Your faculty is held in such high esteem in everyone’s mind, and the name Sorbonne carries such great authority, that, after the sacred councils, there has never been a society in whom people have placed more trust, and not merely in matters of faith, for in human philosophy, too, everyone believes that it is impossible to find anywhere else more perspicuity and solidity, more integrity and wisdom in rendering judgments than among you. Thus, if you deigned to consider this work sufficiently worth the effort and, first of all, were to correct it—for being aware not only of my humanity but also, above all, of my ignorance, I do not claim that there are no errors in it—and, second, were to add what is lacking, perfect what is insufficiently complete, and illustrate what requires further explanation—if you were to do this on your own or at least give me your advice, so that then I could do it—and, finally, once those arguments in the work proving that God exists and that the mind is different from the body have been established and made as clear as I believe they can be, so that they must be truly accepted as extremely accurate proofs, if you were willing to confirm and publicly endorse them, then, if all this happens, I have no doubt that all the errors which have ever existed concerning these two questions will soon be erased from human minds. For truth itself will quickly see to it that other intellectuals and scholars subscribe to your judgment. And your authority will lead the atheists, who tend to be superficial thinkersrather than people with natural acuity or learning, to set aside their spirit of contradiction and perhaps even to take up arms themselves in support of arguments which they know are considered established truths by all those endowed with real intelligence, in order to avoid appearing as if they do not understand them. And finally all the others will quickly accept the evidence of so many testimonials, and there will no longer be anyone in the world who ventures to call into doubt either that God exists or that the human soul is truly distinct from the body. Given your extraordinary wisdom, you yourselves are able to judge better than anyone else how useful this might be. However, it would not be appropriate for me here to commend further the cause of God and religion to those who have always been the greatest support of the Catholic Church.


I have previously touched briefly on questions of God and the human mind in my Discourse on the Method of Reasoning Correctly and Investigating Truth in the Sciences, published in French in the year 1637. In that work, to be sure, my purpose was not to treat them thoroughly but only to consider them generally and to learn from the judgments of my readers how I ought to address them later on. For these questions seemed to me so important that I judged they should be dealt with more than once. And the road I follow in explaining them is so seldom trodden and so remote from the usual path, that I did not think it would be helpful to explain it at length in French and in a discourse which anyone anywhere might read, in case it encouraged those with weaker minds to believe that they, too, should set out along the same route.

However, in that earlier work I asked all those who came across something they considered objectionable in my writings to do me the favour of advising me what that was. Where my remarks on these questions of God and the soul were concerned, they found nothing worth objecting to, except for two things. These comments I will respond to briefly here, before I undertake a more detailed discussion of these matters.

The first objection is as follows: from the fact that the human mind reflecting on itself does not perceive itself to be anything other than a thinking thing, it does not follow that its nature or essence consists merely in its being a thing that thinks, in the sense that this word merely excludes everything else which one might perhaps be able to claim pertains to the nature of the soul. To this objection I reply that in that argument I did not wish to exclude those other attributes in a sequence of thoughts leading to the truth of the matter (which was not really my concern at that time) but only in a sequence following my own perceptions. Thus, what I meant was that I had no distinct awareness of anything which I knew belonged to my essence, other than the fact that I was a thinking thing, or a thing possessing in itself the faculty of thinking. In what follows, however, I will show how from the fact that I know nothing else pertains to my essence, it also follows that there is, in fact, nothing else belonging to it.

The second objection is that from the fact that I have within me the idea of something more perfect than myself, it does not follow that the idea itself is more perfect than I am and, even less, that what is represented by this idea exists. However, my answer to this objection is that here an ambiguity lies concealed in the word idea. For it can be understood materially, as an operation of my intellect, in which sense it cannot be said that it is more perfect than me, or it can be understood objectively, as the thing represented by that operation. Even if we do not assume that this thing exists outside my intellect, it can still be more perfect than I am because of its essence. How it follows merely from the fact that there is within me the idea of something more perfect than myself that this thing truly exists, I will explain in detail in what follows.

In addition to these objections, I have seen two fairly lengthy works, but they were less concerned to attack my reasoning about these matters than my conclusions, using arguments borrowed from sources common among atheists. But arguments like theirs can have no effect on those who understand my reasoning, and the judgments of many people are so perverse and feeble, that they are persuaded by opinions they have earlier adopted, no matter how false and remote from reason they may be, rather than by a true and firm refutation of these opinions which they hear about later on. And so I am unwilling to respond to those criticisms here, because I wish to avoid having to begin by stating them. I will only make the general point that everything atheists commonly toss out to attack the existence of God always depends upon the fact that we attribute human feelings to God or else attribute so much strength and wisdom to our own minds, that we attempt to determine and understand what God can and ought to do. But we will have no difficulty with this type of objection, provided only that we remember to think of our minds as finite things and of God as beyond our comprehension and infinite.

However, now that I have in one way or another taken a preliminary test of people’s opinions, I am here addressing once more the same two questions concerning God and the human mind and at the same time dealing fully with the basic principles of First Philosophy, but not in a way that leads me to expect any praise from the general public or from many readers. In fact, I would even advise people not to read this treatise, unless they are able and willing to meditate seriously with me, to detach their minds from their senses, and at the same time to remove all preconceived notions from their thinking. I know well enough that one finds relatively few readers like that. And as for those who do not take the trouble to understand the order and the connections in my arguments and who are keen to chatter on only about individual conclusi0ns, as many habitually do, such people will not harvest much fruit by reading this treatise. Although they may perhaps find in many parts an occasion to quibble, it will still not be easy for them to make a significant objection or any which merits a reply.

And because I am also not committing myself to satisfying other people in all points immediately and am not arrogant enough to believe that I can foresee everything that will seem difficult to anyone, I will first of all set down in the Meditations the very thoughts with whose help I reached, so it seems to me, a certain and manifest knowledge of the truth, in order to discover whether, using the same arguments which convinced me, I may perhaps be able to persuade others as well. Then, after that, I will reply to the objections of several people of exceptional intelligence and learning to whom I sent these Meditations for their perusal, before I submitted them to the printer. For they have made so many and such varied objections, that I venture to hope it will not be easy for other criticisms—at least ones of any importance—to arise in anyone’s mind which these people have not already touched on. And so I also urge those who read the Meditations not to render judgment on it before they have taken the trouble to read all the objections and my replies to them.(5)


In the First Meditation I set down the reasons which enable us to place everything in doubt, especially material things, at least so long as we do not have foundations for the sciences different from those we have had up to now. Although at first glance the usefulness of such a widespread doubt is not apparent, it is, in fact, very great, because it frees us from all prejudices, sets down the easiest route by which we can detach our minds from our senses, and finally makes it impossible for us to doubt anymore those things which we later discover to be true.

In the Second Meditation, the mind, using its own unique freedom, assumes that all those things about whose existence it can entertain the least doubt do not exist and recognizes that during this time it is impossible that it itself does not exist. And that is also extremely useful, because in this way the mind can easily differentiate between those things pertaining to it, that is, to its intellectual nature, and those pertaining to the body. However, since at this point some people may perhaps expect an argument [proving] the immortality of the soul, I think I should warn them here that I have tried to avoid writing anything which I could not accurately demonstrate and that, therefore, I was unable to follow any sequence of reasoning other than the one used by geometers. That means I start by setting down everything on which the proposition we are looking into depends, before I reach any conclusions about it. Now, the first and most important prerequisite for understanding the immortality of the soul is to form a conception of the soul that is as clear as possible, one entirely distinct from every conception [we have] of the body. And that I have done in this section. After that, it is essential also for us to know that all those things we understand clearly and distinctly are true in a way which matches precisely how we think of them. This I was unable to prove before the Fourth Meditation. We also need to have a distinct conception of corporeal nature. I deal with that point partly in this Second Meditation and partly in the Fifth and Sixth Meditations, as well. And from these we necessarily infer that all those things we conceive clearly and distinctly as different substances, in the same way we think of the mind and the body, are, in fact, truly different substances, distinct from one another, a conclusion I have drawn in the Sixth Meditation. This conclusion is also confirmed in the same meditation from the fact that we cannot think of the body as anything other than something divisible, and, by contrast, [cannot think of] the mind as anything other than something indivisible. For we cannot conceive of half a mind, in the same way we can with a body, no matter how small. Hence, we realize that their natures are not only different but even, in some respects, opposites. However, I have not pursued the matter any further in this treatise, both because these points are enough to show that the annihilation of the mind does not follow from the corruption of the body and that we mortals thus ought to entertain hopes of another life and also because the premises on the basis of which we can infer the immortality of the mind depend upon an explanation of all the principles of physics. For that, first of all, we would have to know that all substances without exception—or those things which, in order to exist, must be created by God—are by their very nature incorruptible and can never cease to exist, unless God, by denying them his concurrence, reduces them to nothing, and then, second, we would have to understand that a body, considered generally, is a substance and thus it, too, never dies.(6) But the human body, to the extent that it differs from other bodies, consists merely of a certain arrangement of parts, with other similar accidental properties; whereas, the human mind is not made up of any accidental properties in this way, but is a pure substance.(7) For even if all the accidental properties of the mind were changed, if, for example, it were to think of different things or have different desires and perceptions, and so on, that would not mean it had turned into a different mind. But the human body becomes something different from the mere fact that the shape of some of its parts has changed. From this it follows that the [human] body does, in fact, perish very easily, but that the mind, thanks to its nature, is immortal.(8)

In the Third Meditation I have set out what seems to me a sufficiently detailed account of my main argument to demonstrate the existence of God. However, in order to lead the minds of the readers as far as possible from the senses, in this section I was unwilling to use any comparisons drawn from corporeal things, and thus many obscurities may still remain. But these, I hope, have later been entirely removed in the replies [I have made] to the objections. For instance, among all the others, there is the issue of how the idea of a supremely perfect being, which is present within us, could have so much objective reality, that it is impossible for it not to originate from a supremely perfect cause. This is illustrated [in the replies] by the comparison with a wholly perfect machine, the idea of which exists in the mind of some craftsman. For just as the objective ingenuity of this idea must have some cause, that is, the technical skill of this craftsman or of someone else from whom he got the idea, so the idea of God, which is in us, cannot have any cause other than God Himself.(9)

In the Fourth Meditation, I establish that all the things which we perceive clearly and distinctly are true, and at the same time I explain what constitutes the nature of falsity, things that we have to know both to confirm what has gone before and to understand what still remains. (However, in the meantime I must observe that in this part I do not deal in any way with sin, that is, with errors committed in pursuit of good and evil, but only with those which are relevant to judgments of what is true and false. Nor do I consider matters relevant to our faith or to the conduct of our lives, but merely those speculative truths we can know only with the assistance of our natural light).(10)

In the Fifth Meditation, I offer a general explanation of corporeal nature and, in addition, also demonstrate the existence of God in a new argument, in which, however, several difficulties may, once again, arise. These I have resolved later in my replies to the objections. And finally, I point out in what sense it is true that the certainty of geometrical demonstrations depends upon a knowledge of God.

Finally, in the Sixth Meditation, I differentiate between the understanding and the imagination and describe the principles of this distinction. I establish that the mind is truly distinct from the body, and I point out how, in spite of that, it is so closely joined to the body that they form, as it were, a single thing. I review all the errors which customarily arise through the senses and explain the ways in which such errors can be avoided. And then finally, I set down all the reasons which enable us to infer the existence of material things. Not that I believe that these are particularly useful because they demonstrate the truth of what they prove, for example, that there is truly is a world, that human beings have bodies, and things like that, which no one of sound mind ever seriously doubted, but rather because, when we examine these reasons, we see that they are neither as firm or as evident as those by which we arrive at a knowledge of our own minds and of God, so that the latter are the most certain and most evident of all things which can be known by the human intellect. The proof of this one point was the goal I set out to attain in these Mediations. For that reason I am not reviewing here various [other] questions I have also dealt with as they arise [in this treatise].


It is now several years since I noticed how from the time of my early youth I had accepted many false claims as true, how everything I had later constructed on top of those [falsehoods] was doubtful, and thus how at some point in my life I needed to tear everything down completely and begin again from the most basic foundations, if I wished to establish something firm and lasting in the sciences. But this seemed an immense undertaking, and I kept waiting, until I would be old enough and sufficiently mature to know that no later period of my life would come [in which I was] better equipped to undertake this disciplined enquiry. This reason made me delay for so long, that I would now be at fault if, by [further] deliberation, I used up the time which still remains to carry out that project. And so today, when I have conveniently rid my mind of all worries and have managed to find myself secure leisure in solitary withdrawal, I will at last find the time here for an earnest and unfettered general demolition of my [former] opinions.

Now, for this task it will not be necessary to show that every opinion I hold is false, something which I might well be incapable of ever carrying out. But since reason now convinces me that I should withhold my assent from opinions which are not entirely certain and indubitable, no less than from those which are plainly false, then, if I uncover any reason for doubt in each of them, that will be enough to reject them all. For that I will not need to run through them separately, a task that would take forever, because once the foundations are destroyed, whatever is built above them will collapse on its own. Thus, I shall at once assault the very principles upon which all my earlier beliefs rested.

Up to this point, what I have accepted as very true I have derived either from the senses or through the senses. However, sometimes I have discovered that these are mistaken, and it is prudent never to place one’s entire trust in things which have deceived us even once.

However, although from time to time the senses deceive us about miniscule things or those further away, it could well be that there are still many others matters about which we cannot entertain the slightest doubt, even though we derive [our knowledge] of them from sense experience, for example, the fact that I am now here, seated by the fire, wearing a winter robe, holding this paper in my hands, and so on. And, in fact, how could I deny that these very hands and this whole body are mine, unless perhaps I were to compare myself with certain insane people whose cerebellums are so troubled by the stubborn vapours of black bile that they constantly claim that they are kings, when, in fact, they are very poor, or that they are dressed in purple, when they are nude, or that they have earthenware heads, or are complete pumpkins, or made of glass? But these people are mad, and I myself would appear no less demented, if I took something from them and applied it to myself as an example.

That is outstanding reasoning—as if I were not a person who in the night habitually sleeps and experiences in my dreams all the same things as these [mad] people do when wide awake, sometimes even less probable ones. How often have I had an experience like this: while sleeping at night, I am convinced that I am here, dressed in a robe and seated by the fire, when, in fact, I am lying between the covers with my clothes off! At the moment, my eyes are certainly wide awake and I am looking at this piece of paper, this head which I am moving is not asleep, and I am aware of this hand as I move it consciously and purposefully. None of what happens while I am asleep is so distinct. Yes, of course—as if I do not recall other times when I, too, have been deceived by similar thoughts in my sleep. As I  reflect on this matter carefully, it becomes completely clear to me that there are no certain indicators which ever enable us to differentiate between being awake and being asleep, so much so that I am astounded, and this confused state itself almost convinces me that I may be sleeping.

So then, let us suppose that I am asleep and that these particular details—that my eyes are open, that I am moving my head, that I am stretching out my hand—are not true and that perhaps I do not even have hands like these or a whole body like this. We must, of course, still concede that the things we see while asleep are like painted images which could only have been made as representations of real things. And so these general things—these eyes, this head, this hand, and this entire body—at least are not imaginary things but really do exist. For even when painters themselves take great care to form sirens and satyrs with the most unusual shapes, they cannot, in fact, give them natures which are entirely new. Instead, they simply mix up the limbs of various animals or, if they happen to come up with something so new that nothing at all like it has been seen before and thus [what they have made] is completely fictitious and false, nonetheless, at least the colours which make up the picture certainly have to be real. For similar reasons, although these general things—eyes, head, hand, and so on—could also be imaginary, still we are at least forced to concede the reality of certain even simpler and more universal objects, out of which, just as with real colours, all those images of things that are in our thoughts, whether true or false, are formed.

To this class [of things], corporeal nature appears, in general, to belong, as well as its extension, the shape of extended things, their quantity or their size and number, the place where they exist, the time which measures how long they last, and things like that.

Thus, from these facts perhaps we are not reaching an erroneous conclusion [by claiming] that physics, astronomy, medicine, and all the other disciplines which rely upon a consideration of composite objects are indeed doubtful, but that arithmetic, geometry, and the other [sciences] like them, which deal with only the simplest and most general matters and have little concern whether or not they exist in the nature of things, contain something certain and indubitable. For whether I am awake or asleep, two and three always add up to five, a square does not have more than four sides, and it does not seem possible that such manifest truths could ever arouse the suspicion that they are false.(11)

Nevertheless, a certain opinion has for a long time been fixed in my mind—that there is an all-powerful God who created me and [made me] just as I am. But how do I know He has not arranged things so that there is no earth at all, no sky, no extended thing, no shape, no magnitude, no place, and yet seen to it that all these things appear to me to exist just as they do now? Besides, given that I sometimes judge that other people make mistakes with the things about which they believe they have the most perfect knowledge, might I not in the same way be wrong every time I add two and three together, or count the sides of a square, or do something simpler, if that can be imagined? Perhaps God is unwilling to deceive me in this way, for He is said to be supremely good. But if it is contrary to the goodness of God to have created me in such a way that I am always deceived, it would also seem foreign to His goodness to allow me to be occasionally deceived. The latter claim, however, is not one that I can make.

Perhaps there may really be some people who prefer to deny [the existence of] such a powerful God, rather than to believe that all other things are uncertain. But let us not seek to refute these people, and [let us concede] that everything [I have said] here about God is a fiction. No matter how they assume I reached where I am now, whether by fate, or chance, or a continuous series of events, or in some other way, given that being deceived and making mistakes would seem to be something of an imperfection, the less power they attribute to the author of my being, the greater the probability that I will be so imperfect that I will always be deceived. To these arguments I really do not have a reply. Instead, I am finally compelled to admit that there is nothing in the beliefs which I formerly held to be true about which one cannot raise doubts. And this is not a reckless or frivolous opinion, but the product of strong and well-considered reasoning. And therefore, if I desire to discover something certain, in future I should also withhold my assent from those former opinions of mine, no less than [I do] from opinions which are obviously false.

But it is not sufficient to have called attention to this point. I must [also] be careful to remember it. For these habitual opinions constantly recur, and I have made use of them for so long and they are so familiar that they have, as it were, acquired the right to seize hold of my belief and subjugate it, even against my wishes, and I will never give up the habit of deferring to and relying on them, so long as I continue to assume that they are what they truly are, that is, opinions which are to some extent doubtful, as I have already pointed out, but still very probable, so that it is much more reasonable to believe them than to deny them. For that reason, I will not go wrong, in my view, if I deliberately turn my inclination into its complete opposite and deceive myself, [by assuming] for a certain period that these earlier opinions are entirely false and imaginary, until I have, as it were, finally brought the weight of both my [old and my new] prejudices into an equal balance, so that corrupting habits will no longer twist my judgment away from the correct perception of things. For I know that doing this will not, for the time being, lead to danger or error and that it is impossible for me to indulge in excessive distrust, since I am not at this point concerned with actions, but only with knowledge.(12)

Therefore, I will assume that it is not God, who is supremely good and the fountain of truth, but some malicious demon, at once omnipotent and supremely cunning, who has been using all the energy he possesses to deceive me. I will suppose that sky, air, earth, colours, shapes, sounds, and all other external things are nothing but the illusions of my dreams with which this spirit has set traps for my credulity. I will think of myself as if I had no hands, no eyes, no flesh, no blood, nor any senses, and yet as if I still falsely believed I had all these things. I shall continue to concentrate resolutely on this meditation, and if, in doing so, I am, in fact, unable to learn anything true, I will at least do what is in my power and with a resolute mind take care not to agree to what is false or to enable the deceiver to impose anything on me, no matter how powerful and cunning [he may be]. But this task is onerous, and a certain idleness brings me back to my customary way of life. I am not unlike a prisoner who in his sleep may happen to enjoy an imaginary liberty and who, when he later begins to suspect that he is asleep, fears to wake up and willingly cooperates with the pleasing illusions [in order to prolong them]. In this way, I unconsciously slip back into my old opinions and am afraid of waking up, in case from now on I would have to spend the period of challenging wakefulness that follows this peaceful relaxation not in the light, but in the inextricable darkness of the difficulties I have just raised.


Yesterday’s meditation threw me into so many doubts that I can no longer forget them or even see how they might be resolved. Just as if I had suddenly fallen into a deep eddying current, I am hurled into such confusion that I am unable to set my feet on the bottom or swim to the surface. However, I will struggle along and try once again [to follow] the same path I started on yesterday, that is, I will reject everything which admits of the slightest doubt, just as if I had discovered it was completely false, and I will proceed further in this way, until I find something certain, or at least, if I do nothing else, until I know for certain that there is nothing certain. In order to shift the entire earth from its location, Archimedes asked for nothing but a fixed and immovable point. So I, too, ought to hope for great things if I can discover something, no matter how small, which is certain and immovable.

Therefore, I assume that everything I see is false. I believe that none of those things my lying memory represents has ever existed, that I have no senses at all, and that body, shape, extension, motion, and location are chimeras.(13) What, then, will be true? Perhaps this one thing: there is nothing certain.

But how do I know there is not something different from all these things I have just listed, about which one could not entertain the slightest momentary doubt? Is there not some God, by whatever name I call him, who places these very thoughts inside me? But why would I think this, since I myself could perhaps have produced them? So am I then not at least something? But I have already denied that I have senses and a body. Still, I am puzzled, for what follows from this? Am I so bound up with my body and my senses that I cannot exist without them? But I have convinced myself that there is nothing at all in the universe—no sky, no earth, no minds, no bodies. So then, is it the case that I, too, do not exist? No, not at all: if I persuaded myself of something, then I certainly existed. But there is some kind of deceiver, supremely powerful and supremely cunning, who is constantly and intentionally deceiving me. But then, if he is deceiving me, there is no doubt that I, too, for that very reason exist. Let him trick me as much as he can, he will never succeed in making me nothing, as long as I am aware that I am something. And so, after thinking all these things through in great detail, I must finally settle on this proposition: the statement I am, I exist is necessarily true every time I say it or conceive of it in my mind.

But I do not yet understand enough about what this I is, which now necessarily exists. Thus, I must be careful I do not perhaps unconsciously substitute something else in place of this I and in that way make a mistake even in the conception which I assert is the most certain and most evident of all. For that reason, I will now reconsider what I once believed myself to be, before I fell into this [present] way of thinking. Then I will remove from that whatever could in the slightest way be weakened by the reasoning I have [just] brought to bear, so that, in doing this, by the end I will be left only with what is absolutely certain and immovable.

What then did I believe I was before? Naturally, I thought I was a human being. But what is a human being? Shall I say a rational animal? No. For then I would have to ask what an animal is and what rational means, and thus from a single question I would fall into several greater difficulties. And at the moment I do not have so much leisure time, that I wish to squander it with subtleties of this sort. Instead I would prefer here to attend to what used to come into my mind quite naturally and spontaneously in earlier days every time I thought about what I was. The first thought, of course, was that I had a face, hands, arms, and this entire mechanism of limbs, the kind one sees on a corpse, and this I designated by the name body. Then it occurred to me that I was nourished and that I walked, felt, and thought. These actions I assigned to the soul. But I did not reflect on what this soul might be, or else I imagined it as some kind of attenuated substance, like wind, or fire, or aether, spread all through my denser parts. However, I had no doubts at all about my body—I thought I had a clear knowledge of its nature. Perhaps if I had attempted to describe it using the mental conception I used to hold, I would have explained it as follows: By a body I understand everything that is appropriately bound together in a certain form and confined to a place; it fills a certain space in such a way as to exclude from that space every other body; it can be perceived by touch, sight, hearing, taste, or smell, and can also be moved in various ways, not, indeed, by itself, but by something else which makes contact with it. For I judged that possessing the power of self-movement, like the ability to perceive things or to think, did not pertain at all to the nature of body. Quite the opposite in fact, so that when I found out that faculties rather similar to these were present in certain bodies, I was astonished.

But what [am I] now, when I assume that there is some extremely powerful and, if I may be permitted to speak like this, malignant and deceiving being who is deliberately using all his power to trick me? Can I affirm that I possess even the least of all those things which I have just described as pertaining to the nature of body? I direct my attention [to this], think [about it], and turn [the question] over in my mind. Nothing comes to me. It is tedious and useless to go over the same things once again. What, then, of those things I used to attribute to the soul, like nourishment or walking? But given that now I do not possess a body, these are nothing but imaginary figments. What about sense perception? This, too, surely does not occur without the body. And in sleep I have apparently sensed many objects which I later noticed I had not [truly] perceived. What about thinking? Here I discover something: thinking does exist. This is the only thing which cannot be detached from me. I am, I exist—that is certain. But for how long? Surely for as long as I am thinking. For it could perhaps be the case that, if I were to abandon thinking altogether, then in that moment I would completely cease to be.At this point I am not agreeing to anything except what is necessarily true. Therefore, strictly speaking, I am merely a thinking thing, that is, a mind or spirit, or understanding, or reason—words whose significance I did not realize before. However, I am something real, and I truly exist. But what kind of thing? As I have said, a thing that thinks.(14)

And what else besides? I will let my imagination roam. I am not that interconnection of limbs we call a human body. Nor am I even some attenuated air which filters through those limbs—wind, or fire, or vapour, or breath, or anything I picture to myself. For I have assumed those things were nothing. Let this assumption hold. Nonetheless, I am still something. Perhaps it could be the case that these very things which I assume are nothing, because they are unknown to me, are truly no different from that I which I do recognize. I am not sure, and I will not dispute this point right now. I can render judgment only on those things which are known to me: I know that I exist. I am asking what this I is—the thing I know. It is very certain that knowledge of this I, precisely defined like this, does not depend on things whose existence I as yet know nothing about and therefore on any of those things I conjure up in my imagination. And this phrase conjure up warns me of my mistake, for I would truly be conjuring something up if I imagined myself to be something, since imagining is nothing other than contemplating the form or the image of a physical thing. But now I know for certain that I exist and, at the same time, that it is possible for all those images and, in general, whatever relates to the nature of body to be nothing but dreams [or chimeras]. Having noticed this, it seems no less foolish for me to say “I will let my imagination work, so that I may recognize more clearly what I am” than if I were to state, “Now I am indeed awake, and I see some truth, but because I do yet not see it with sufficient clarity, I will quite deliberately go to sleep, so that in my dreams I will get a truer and more distinct picture of it.” Therefore, I realize that none of those things which I can understand with the aid of my imagination is pertinent to this idea I possess about myself and that I must be extremely careful to summon my mind back from such things, so that it may perceive its own nature on its own with the utmost clarity.

But what then am I? A thinking thing. What is this? It is surely something that doubts, understands, affirms, denies, is willing, is unwilling, and also imagines and perceives.

This is certainly not an insubstantial list, if all [these] things belong to me. But why should they not? Surely I am the same I who now doubts almost everything, yet understands some things, who affirms that this one thing is true, denies all the rest, desires to know more, does not wish to be deceived, imagines many things, even against its will, and also notices many things which seem to come from the senses? Even if I am always asleep and even if the one who created me is also doing all he can to deceive me, what is there among all these things which is not just as true as the fact that I exist? Is there something there that I could say is separate from me? For it is so evident that I am the one who doubts, understands, and wills, that I cannot think of anything which might explain the matter more clearly. But obviously it is the same I that imagines, for although it may well be case, as I have earlier assumed, that nothing I directly imagine is true, nevertheless, the power of imagining really exists and forms part of my thinking. Finally, it is the same I that feels, or notices corporeal things, apparently through the senses: for example, I now see light, hear noise, and feel heat. But these are false, for I am asleep. Still, I certainly seem to see, hear, and grow warm—and this cannot be false. Strictly speaking, this is what in me is called sense perception and, taken in this precise meaning, it is nothing other than thinking.

From these thoughts, I begin to understand somewhat better what I am. However, it still appears that I cannot prevent myself from thinking that corporeal things, whose images are formed by thought and which the senses themselves investigate, are much more distinctly known than that obscure part of me, the I, which is not something I can imagine, even though it is really strange that I have a clearer sense of those things whose existence I know is doubtful, unknown, and alien to me than I do of something which is true and known, in a word, of my own self. But I realize what the matter is. My mind loves to wander and is not yet allowing itself to be confined within the limits of the truth. All right, then, let us at this point for once give it completely free rein, so that a little later on, when the time comes to pull back, it will consent to be controlled more easily.

Let us consider those things we commonly believe we understand most distinctly of all, that is, the bodies we touch and see—not, indeed, bodies in general, for those general perceptions tend to be somewhat more confusing, but rather one body in particular. For example, let us take this [piece of] wax. It was collected from the hive very recently and has not yet lost all the sweetness of its honey. It [still] retains some of the scent of the flowers from which it was gathered. Its colour, shape, and size are evident. It is hard, cold, and easy to handle. If you strike it with your finger, it will give off a sound. In short, everything we require to be able to recognize a body as distinctly as possible appears to be present. But watch. While I am speaking, I bring the wax over to the fire. What is left of its taste is removed, its smell disappears, its colour changes, its shape is destroyed, its size increases, it turns to liquid, and it gets hot. I can hardly touch it. And now, if you strike it, it emits no sound. After [these changes], is what remains the same wax? We must concede that it is. No one denies this; no one thinks otherwise. What then was in [this piece of wax] that I understood so distinctly? Certainly nothing I apprehended with my senses, since all [those things] associated with taste, odour, vision, touch, and sound have now changed. [But] the wax remains.

Perhaps what I now think is as follows: the wax itself was not really that sweetness of honey, that fragrance of flowers, that white colour, or that shape and sound, but a body which a little earlier appeared perceptible to me in those forms, but which is now [perceptible] in different ones. But what exactly is it that I am imagining in this way? Let us consider that point and, by removing those things which do not belong to the wax, see what is left over. It is clear that nothing [remains], other than something extended, flexible, and changeable. But what, in fact, do flexible and changeable mean? Do these words mean that I imagine that this wax can change from a round shape to a square one or from [something square] to something triangular? No, that is not it at all. For I understand that the wax has the capacity for innumerable changes of this kind, and yet I am not able to run through these innumerable changes by using my imagination. Therefore, this conception [I have of the wax] is not produced by the faculty of imagination. What about extension? Is not the extension of the wax also unknown? For it becomes greater when the wax melts, greater [still] when it boils, and once again [even] greater, if the heat is increased. And I would not be judging correctly what wax is if I did not believe that it could also be extended in various other ways, more than I could ever grasp in my imagination. Therefore, I am forced to admit that my imagination has no idea at all what this wax is and that I perceive it only with my mind. I am talking about this [piece of] wax in particular, for the point is even clearer about wax in general.(15) But what is this wax which can be perceived only by the mind? It must be the same as the wax I see, touch, and imagine—in short, the same wax I thought it was from the beginning. But we should note that the perception of it is not a matter of sight, or touch, or imagination, and never was, even though that seemed to be the case earlier, but simply of mental inspection, which could be either imperfect and confused as it was before, or clear and distinct as it is now, depending on the lesser or greater degree of attention I bring to bear on those things out of which the wax is composed.

However, now I am amazed at how my mind is [weak and] prone to error. For although I am considering these things silently within myself, without speaking aloud, I still get stuck on the words themselves and am almost deceived by the very nature of the way we speak. For if the wax is there [in front of us], we say that we see the wax itself, not that we judge it to be there from the colour or shape. From that I could immediately conclude that I recognized the wax thanks to the vision in my eyes, and not simply by mental inspection, unless by chance I happen at that moment to glance out of the window at people crossing the street, for in normal speech I also say I see the people themselves, just as I do with the wax. But what am I really seeing other than hats and coats, which could be concealing automatons underneath? However, I judge that they are people. And thus what I thought I was seeing with my eyes I understand only with my faculty of judgment, which is in my mind.

But someone who wishes [to elevate] his knowledge above the common level should be ashamed to have looked for uncertainty in the forms of speech which ordinary people use, and so we should move on to consider next whether my perception of what wax is was more perfect and more evident when I first perceived it and believed I knew it by my external senses, or at least by my so-called common sense, in other words, by the power of imagination, or whether it is more perfect now, after I have investigated more carefully both what wax is and how it can be known.(16) To entertain doubts about this matter would certainly be silly. For in my first perception of the wax what was distinct? What did I notice there that any animal might not be capable of capturing? But when I distinguish the wax from its external forms and look at it as something naked, as if I had stripped off its clothing, even though there could still be some error in my judgment, it is certain that I could not perceive it in this way without a human mind.

But what am I to say about this mind itself, in other words, about myself? For up to this point I am not admitting there is anything in me except mind. What, I say, is the I that seems to perceive this wax so distinctly? Do I not know myself not only much more truly and certainly, but also much more distinctly and clearly than I know the wax? For if I judge that the wax exists from the fact that I see it, then from the very fact that I see the wax it certainly follows much more clearly that I myself also exist. For it could be that what I see is not really wax. It could be the case that I do not have eyes at all with which to see anything. But when I see or think I see (at the moment I am not differentiating between these two), it is completely impossible that I, the one doing the thinking, am not something. For similar reasons, if I judge that the wax exists from the fact that I am touching it, the same conclusion follows once again, namely, that I exist. The result is clearly the same if [my judgment rests] on the fact that I imagine the wax or on any other reason at all. But these observations I have made about the wax can be applied to all other things located outside of me. Furthermore, if my perception of the wax seemed more distinct after it was drawn to my attention, not merely by sight or touch, but by several [other] causes, I must concede that I now understand myself much more distinctly, since all of those same reasons capable of assisting my perception either of the wax or of any other body whatsoever are even better proofs of the nature of my mind! However, over and above this, there are so many other things in the mind itself which can provide a more distinct conception of its [nature] that it hardly seems worthwhile to review those features of corporeal things which might contribute to it.

And behold—I have all on my own finally returned to the place where I wanted to be. For since I am now aware that bodies themselves are not properly perceived by the senses or by the faculty of imagination, but only by the intellect, and are not perceived because they are touched or seen, but only because they are understood, I realize this obvious point: there is nothing I can perceive more easily or more clearly than my own mind. But because it is impossible to rid oneself so quickly of an opinion one has long been accustomed to hold, I would like to pause here, in order to impress this new knowledge more deeply on my memory with a prolonged meditation.


Now I will close my eyes, stop up my ears, and withdraw all my senses. I will even blot out from my thinking all images of corporeal things, or else, since this is hardly possible, I will dismiss them as empty and false images of nothing at all, and by talking only to myself and looking more deeply within, I will attempt, little by little, to acquire a greater knowledge of and more familiarity with myself. I am a thinking thing, in other words, something that doubts, affirms, denies, knows a few things, is ignorant of many things, wills, refuses, and also imagines and feels. For, as I have pointed out earlier, although those things which I sense or imagine outside of myself are perhaps nothing, nevertheless, I am certain that the thought processes I call sense experience and imagination, given that they are only certain modes of thinking, do exist within me.

In these few words, I have reviewed everything I truly know, or at least [everything] that, up to this point, I was aware I knew. Now I will look around more diligently, in case there are perhaps other things in me that I have not yet considered. I am certain that I am a thinking thing. But if that is the case, do I not then also know what is required for me to be certain about something? There is, to be sure, nothing in this first knowledge other than a certain clear and distinct perception of what I am affirming, and obviously this would not be enough for me to be certain about the truth of the matter, if it could ever happen that something I perceived just as clearly and distinctly was false. And so it seems to me that now I can propose the following general rule: all those things I perceive very clearly and very distinctly are true.

However, before now I have accepted as totally certain and evident many things that I have later discovered to be doubtful. What, then, were these things? [They were], of course, the earth, the sky, the stars, and all the other things I used to grasp with my senses. But what did I clearly perceive in them? Obviously I was observing in my mind ideas or thoughts of such things. And even now I do not deny that those ideas exist within me. However, there was something else which I held to be true and which, because I was in the habit of believing it, I also thought I perceived clearly, although I really was not perceiving it at all, namely, that certain things existed outside of me from which those ideas proceeded and which were like them in every way. And here was where I went wrong, or if I was judging truthfully, that certainly had nothing to do with the strength of my perception.

What [then was] true? When I was thinking about something very simple and easy in arithmetic or geometry—for example, that two and three added together make five, and things of that sort—was I not recognizing these with sufficient clarity at least to affirm that they were true? Later on, to be sure, I did judge that such things could be doubted, but the only reason I did so was that it crossed my mind that some God could perhaps have placed within me a certain kind of nature, so that I deceived myself even about those things which appeared most obvious. And every time this preconceived opinion about the supreme power of God occurs to me, I cannot but confess that if He wished, it would be easy for Him to see to it that I go astray, even in those matters which I think I see as clearly as possible with my mind’s eye. But whenever I turn my attention to those very things which I think I perceive with great clarity, I am so completely persuaded by them, that I spontaneously burst out with the following words: Let whoever can deceive me, do so; he will still never succeed in making me nothing, not while I think I am something, or in making it true someday that I never existed, since it is true that I exist now, or perhaps even in making two and three, when added together, more or less than five, or anything like that, in which I clearly recognize a manifest contradiction. And since I have no reason to think that some God exists who is a deceiver and since, up to this point, I do not know enough to state whether there is a God at all, it is clear that the reason for any doubt which rests on this opinion alone is very tenuous and, if I may say so, metaphysical. However, to remove even that doubt, as soon as the occasion presents itself, I ought to examine whether God exists and, if He does, whether He can be a deceiver. For as long as this point remains obscure, it seems to me that I can never be completely certain about anything else.(17)

But now an orderly arrangement would seem to require that I first divide all of my thoughts into certain kinds and look into which of these [kinds], strictly speaking, contain truth or error. Some of my thoughts are, so to speak, images of things, and for these alone the name idea is appropriate, for example, when I think of a man, or a chimera, or the sky, or an angel, or God. But other thoughts, in addition to these, possess certain other forms. For example, when I will, when I fear, when I affirm, and when I deny, I always apprehend something as the object of my thinking, but in my thought I also grasp something more than the representation of that thing. In this [group of thoughts], some are called volitions or feelings, and others judgments.

Now, where ideas are concerned, if I consider these only in and of themselves and do not refer them to anything else, they cannot, strictly speaking, be false. For whether I imagine a goat or a chimera, it is no less true that I imagine one than it is that I imagine the other. And we also need have no fear of error in willing or in feeling, for although I can desire something evil or even things which have never existed, that still does not make the fact that I desire them untrue. And thus, all that remains are judgments, in which I must take care not to be deceived. But the most important and most frequent error I can discover in judgments consists of the fact that I judge the ideas within me are similar to or conform to certain things located outside myself. For obviously, if I considered ideas themselves only as certain modes of my thinking, without referring them to anything else, they would hardly furnish me any material for making a mistake.

Of these ideas, some, it seems to me, are innate, others come from outside, and still others I have myself made up. For the fact that I understand what a thing is, what truth is, and what thinking is I seem to possess from no source other than my own nature. But if I now hear a noise, see the sun, or feel heat, I have up to now judged that [these sensations] come from certain things placed outside of me. And, finally, sirens, hippogriffs, and such like are things I myself dream up.(18) But I could also perhaps believe that all [these ideas] come from outside, or else are all innate, or else are all made up, for I have not yet clearly perceived their true origin.

However, the most important point I have to explore here concerns those ideas which I think of as being derived from objects existing outside me: What reason leads me to suppose that these ideas are similar to those objects? It certainly seems that I am taught to think this way by nature. Furthermore, I know by experience that these [ideas] do not depend on my will and therefore not on me myself, for they often present themselves to me even against my will. For example, whether I will it or not, I now feel heat, and thus I believe that the feeling or the idea of heat reaches me from some object apart from me, that is, from [the heat] of the fire I am sitting beside. And nothing is more obvious than my judgment that this object is sending its own likeness into me rather than something else.

I will now see whether these reasons are sufficiently strong. When I say here that I have been taught to think this way by nature, I understand only that I have been carried by a certain spontaneous impulse to believe it, not that some natural light has revealed its truth to me. There is an important difference between these two things. For whatever natural light reveals to me—for example, that from the fact that I am doubting, it follows that I exist, and things like that—cannot admit of any possible doubt, because there cannot be another faculty [in me] as trustworthy as natural light, one which could teach me that the ideas [derived from natural light] are not true. But where natural impulses are concerned, in the past, when there was an issue of choosing the good thing to do, I often judged that such impulses were pushing me in the direction of something worse, and I do not see why I should place more trust in them in any other matters.

Moreover, although those ideas do not depend on my will, it is not therefore the case that they must come from objects located outside of me. For just as those impulses I have been talking about above are within me and yet seem to be different from my will, so perhaps there is also some other faculty in me, one I do not yet understand sufficiently, which produces those ideas, in the same way they have always appeared to be formed in me up to now while I sleep, without the help of any external objects [which they represent].

Finally, even if these ideas did come from things different from me, it does not therefore follow that they have to be like those things. Quite the contrary, for in numerous cases I seem to have often observed a great difference [between the object and the idea]. So, for example, I find in my mind two different ideas of the sun. One, which is apparently derived from the senses and should certainly be included among what I consider ideas coming from outside, makes the sun appear very small to me. However, the other, which is derived from astronomical reasoning, that is, elicited by certain notions innate in me or else produced by me in some other manner, makes the sun appear many times larger than the earth. Clearly, these two [ideas] cannot both resemble the sun which exists outside of me, and reason convinces [me] that the one which seems to have emanated most immediately from the sun itself is the least like it.

All these points offer me sufficient proof that previously, when I believed that certain things existed apart from me that conveyed ideas or images of themselves, whether by my organs of sense or by some other means, my judgment was not based on anything certain but only on some blind impulse.

However, it crosses my mind that there is still another way of exploring whether certain things of which I have ideas within me exist outside of me. To the extent that those ideas are [considered] merely certain ways of thinking, of course, I do not recognize any inequality among them, and they all appear to proceed from me in the same way. But to the extent that one idea represents one thing, while another idea represents something else, it is clear that they are very different from each other. For undoubtedly those that represent substances to me and contain in themselves more objective reality, so to speak, are something more than those that simply represent modes or accidents. And, once again, that idea thanks to which I am aware of a supreme God—eternal, infinite, omniscient, omnipotent, the Creator of all things that exist outside of Him—certainly has more objective reality in it than those ideas through which finite substances are represented.(19)

Now, it is surely evident by natural light that there must be at least as much [reality] in the efficient and total cause as there is in the effect of this cause. For from where, I would like to know, can the effect receive its reality if not from its cause? And how can the cause provide this reality to the effect, unless the cause also possesses it? But from this it follows that something cannot be made from nothing and also that what is more perfect, that is, contains more reality in itself, cannot be produced from what is less perfect. This is obviously true not only of those effects whose reality is [what the philosophers call] actual or formal, but also of those ideas in which we consider only [what they call] objective reality.(20) For example, some stone which has not existed yet cannot now begin to exist, unless it is produced by something which has in it, either formally or eminently, everything that goes into the stone, and heat cannot be brought into an object which was not warm previously, except by something which is of an order at least as perfect as heat, and so on with all the other examples. But beyond this, even the idea of heat or of the stone cannot exist within me, unless it is placed in me by some cause containing at least as much reality as I understand to be in the heat or in the stone. For although that cause does not transfer anything of its own reality, either actual or formal, into my idea, one should not therefore assume that [this cause] must be less real. Instead, [we should consider] that the nature of the idea itself is such that it requires from itself no formal reality other than what it derives from my own thinking, of which it is a mode [that is, a way or style of thinking]. But for the idea to possess this objective reality rather than another, it must surely obtain it from some cause in which there is at least as much formal reality as the objective reality contained in the idea itself. For if we assume that something can be discovered in the idea which was not present in its cause, then it must have obtained this from nothing. But no matter how imperfect the mode of being may be by which a thing is objectively present in the understanding through its idea, that mode is certainly not nothing, and therefore [this idea] cannot come from nothing.(21)

And although the reality which I am considering in my ideas is only objective, I must not  imagine that it is not necessary for the same reality to exist formally in the causes of those ideas but that it is sufficient if [the reality] in them is objective, as well. For just as that mode of existing objectively belongs to ideas by their very nature, so the mode of existing formally belongs to the causes of [these] ideas, at least to the first and most important causes, by their nature. And although it may well be possible for one idea to be born from another, still this regress cannot continue on ad infinitum, for we must finally come to some first [idea], whose cause is, as it were, the archetype [or original idea], which formally contains the entire reality that exists only objectively in the idea. And thus natural light makes it clear to me that ideas exist within me as certain images that can, in fact, easily fall short of the perfection of the things from which they were derived but that cannot contain anything greater or more perfect than those things do.

And the more time and care I take examining these things, the more clearly and distinctly I recognize their truth. But what am I finally to conclude from them? It is clear that if the objective reality of any of my ideas is so great that I am certain that the same reality is not in me either formally or eminently and that therefore I myself cannot be the cause of that idea, it necessarily follows that I am not alone in the world but that some other thing also exists which is the cause of that idea.(22) But if I do not find any such idea within me, then I will obviously have no argument that confirms for me the existence of anything beyond myself. For I have been searching very diligently and have not been able to find any other argument up to now.

But of these ideas of mine, apart from the one which reveals my own self to me, about which there can be no difficulty, there is another [that represents] God [to me], and there are others which represent corporeal and inanimate things, as well as others representing angels, animals, and finally other men who resemble me.

As far as concerns those ideas which display other human beings or animals or angels, I understand readily enough that I could have put these together from ideas I have of myself, of corporeal things, and of God, even though, apart from me, there might be no people or animals or angels in the world.

Where the ideas of corporeal things are concerned, I see nothing in them so great that it seems as if it could not have originated within me. For if I inspect these ideas thoroughly and examine them individually in the same way I did yesterday with the idea of the wax, I notice that there are only a very few things I perceive in them clearly and distinctly, for example, magnitude or extension in length, breadth, and depth; shape, which emerges from the limits of that extension; position, which different forms derive from their relation to each other; and motion or a change of location. To these one can add substance, duration, and number. However, with the other things, like light, colours, sounds, odours, tastes, heat, cold, and other tactile qualities, my thoughts of them involve so much confusion and obscurity, that I still do not know whether they are true or false, in other words, whether the ideas I have of these [qualities] are ideas of things or of non-things. For although I observed a little earlier that falsehood or, strictly speaking, formal falsehood could occur only in judgments, nonetheless there is, in fact, a certain other material falsehood in ideas, when they represent a non-thing as if it were a thing. Thus, for example, ideas which I have of heat and cold are so unclear and indistinct that I am not able to learn from them whether cold is merely a lack of heat, or heat a lack of cold, or whether both of these are real qualities, or whether neither [of them is]. And because there can be no ideas which are not, as it were, ideas of things, if it is indeed true that cold is nothing other than a lack of heat, the idea which represents cold to me as if it were something positive and real will not improperly be called false, and that will also hold for all other ideas [like this].

To such ideas I obviously do not have to assign any author other than myself, for, if they are, in fact, false, that is, if they represent things which do not exist, my natural light informs me that they proceed from nothing, in other words, that they are in me only because there is something lacking in my nature, which is not wholly perfect. If, on the other hand, they are true, given that the reality they present to me is so small that I cannot distinguish the object from something which does not exist, then I do not see why I could not have come up with them myself.

As for those details which are clear and distinct in my ideas of corporeal things, some of them, it seems to me, I surely could have borrowed from the idea of myself, namely, substance, duration, number, and other things like that. For when I think that a stone is a substance, or something equipped to exist on its own and that I, too, am a substance, even though I conceive of myself as a thinking and non-extended thing and of the stone as an extended thing which does not think, so that there is the greatest difference between the two conceptions, they both still seem to fit the category of substance. In the same way, when I perceive that I now exist and also remember that I have existed for some time earlier and when I have various thoughts whose number I recognize, I acquire ideas of duration and number, which I can then transfer to any other things I choose. As for all the other qualities from which I put together my ideas of corporeal things, that is, extension, shape, location, and motion, they are, it is true, not formally contained in me, since I am nothing other than a thinking thing, but because they are merely certain modes of a substance and I, too, am a substance, it seems that they could be contained in me eminently.(23)

And so the only thing remaining is the idea of God. I must consider whether there is anything in this idea for which I myself could not have been the origin. By the name God I understand a certain infinite, [eternal, immutable,] independent, supremely intelligent, and supremely powerful substance by which I myself was created, along with everything else that exists, if, [in fact], anything else does exist. All of these [properties] are clearly [so great] that the more diligently I focus on them, the less it seems that I could have brought them into being by myself alone. And thus, from what I have said earlier, I logically have to conclude that God necessarily exists.

For although the idea of a substance is, indeed, in me by the very fact that I am a substance, that still does not mean [that I possess] the idea of an infinite substance, since I am finite, unless it originates in some other substance which is truly infinite.

And I should not think that my perception of the infinite comes, not from a true idea, but merely from a negation of the finite, in [same] way I perceive rest and darkness by a negation of motion and light. For, on the contrary, I understand clearly that there is more reality in an infinite substance than in a finite one and that therefore my perception of the infinite is somehow in me before my perception of the finite, in other words, my perception of God comes before my perception of myself. For how would I know that I am doubting or desiring, or, in other words, that something is lacking in me and that I am not entirely perfect, unless some idea of a perfect being was in me and I recognized my defects by a comparison?(24)

And one cannot claim that this idea of God might well be materially false and thus could have come from nothing, the way I observed a little earlier with the ideas of heat and cold and things like that. Quite the reverse: for [this idea] is extremely clear and distinct and contains more objective reality than any other, and thus no idea will be found which is more inherently true and in which there is less suspicion of falsehood. This idea, I say, of a supremely perfect and infinite being is utterly true, for although it may well be possible to imagine that such a being does not exist, it is still impossible to imagine that the idea of Him does not reveal anything real to me, in the way I talked above about the idea of cold. This idea of a perfect Being is also entirely clear and distinct, for whatever I see clearly and distinctly which is real and true and which introduces some perfection is totally contained within [this idea]. The fact that I cannot comprehend the infinite or that there are innumerable other things in God that I do not understand or even perhaps have any way of contacting in my thoughts—all this is irrelevant. For something finite, like myself, cannot comprehend the nature of the infinite, and it is sufficient that I understand this very point and judge that all things which I perceive clearly and which I know convey some perfection, as well as innumerable others perhaps which I know nothing about, are in God, either formally or eminently, so that the idea I have of Him is the truest, clearest, and most distinct of all the ideas within me.

But perhaps I am something more than I myself understand, and all those perfections which I attribute to God are potentially in me somehow, even though they are not yet evident and are not manifesting themselves in action. For I already know by experience that my knowledge is gradually increasing, and I do not see anything which could prevent it from increasing more and more to infinity. Nor do I even know of any reasons why, with my knowledge augmented in this way, I could not, with its help, acquire all the other perfections of God or, finally, why, if the power [to acquire] those perfections is already in me, it would not be sufficient to produce the idea of those perfections.

And yet none of these things is possible. For, in the first place, although it is true that my knowledge is gradually increasing and that there are potentially many things within me which have not yet been realized, still none of these is relevant to the idea of God, in which, of course, nothing at all exists potentially. For the very fact that my knowledge is increasing little by little is the most certain argument for its imperfection. Beyond that, even if my knowledge is always growing more and more, nonetheless, that does not convince me that it will ever be truly infinite, since it can never reach a stage where it is not capable of increasing any further. But I judge that God is actually infinite, so that nothing can possibly be added to His perfection. And lastly, I perceive that the objective existence of an idea cannot be produced from a being that is merely potential, which, strictly speaking, is nothing, but only from something which actually or formally exists.

Obviously there is nothing in all these thoughts that is not evident to the natural light in anyone who reflects carefully [on the matter]. But when I pay less attention and when images of sensible things obscure the vision in my mind, I do not so readily remember why the idea of a being more perfect than myself must necessarily proceed from some entity that is truly more perfect than me. Therefore, I would like to enquire further whether I, who possess this idea [of God], could exist if such a being did not exist.

If that were the case, then from whom would I derive my existence? Clearly from myself or from my parents or from some other source less perfect than God. For we cannot think of or imagine anything more perfect than God or even anything equally perfect.

However, if I originated from myself, then I would not doubt or hope, and I would lack nothing at all, for I would have given myself all the perfections of which I have any idea within me, and thus I myself would be God. I must not assume that those things which I lack could well be more difficult to acquire than those now within me. On the contrary, it clearly would have been much more difficult for me—that is, a thinking thing or substance—to emerge from nothing than to acquire a knowledge of the many things about which I am ignorant, for knowing such things is merely an accident of that thinking substance. And surely if I had obtained from myself that greater perfection [of being the author of my own existence], then I could hardly have denied myself the perfections which are easier to acquire, or, indeed, any of those I perceive contained in the idea of God, since, it seems to me, none of them is more difficult to produce. But if there were some perfections more difficult to acquire, they would certainly appear more difficult to me, too, if, indeed, everything else I possessed was derived from myself, because from them I would learn by experience that my power was limited.

And I will not escape the force of these arguments by assuming that I might perhaps have always been the way I am now, as if it followed from that assumption that I would not have to seek out any author for my own existence. For since the entire period of my life can be divided into innumerable parts, each individual one of which is in no way dependent on the others, therefore, just because I existed a little while ago, it does not follow that I must exist now, unless at this very moment some cause is, at it were, creating me once again, in other words, preserving me. For it is clear to anyone who directs attention to the nature of time that, in order for the existence of anything at all to be preserved in each particular moment it lasts, that thing surely needs the same force and action which would be necessary to create it anew, assuming it did not yet exist. Thus, one of the things natural light reveals is that preservation and creation are different only in the ways we think of them.

Consequently, I now ought to ask myself whether I have any power which enables me to bring it about that I, who am now existing, will also exist a little later on, for since I am nothing other than a thinking thing—or at least since my precise concern at the moment is only with that part of me which is a thinking thing—if such a power is in me, I would undoubtedly be conscious of it. But I experience nothing [of that sort], and from this fact alone I recognize with the utmost clarity that I depend upon some being different from myself.

But perhaps that being is not God, and I have been produced by my parents or by some other causes less perfect than God. But [that is impossible]. As I have already said before, it is clear that there must be at least as much [reality] in the cause as in the effect and that thus, since I am a thinking thing and have a certain idea of God within me, whatever I finally designate as my own cause, I must concede that it is also a thinking substance containing the idea of all the perfections I attribute to God. It is possible once again to ask whether that cause originates from itself or from something else. If it comes from itself, then, given what I have said, it is obvious that the cause itself is God. For clearly, if it derives its power of existing from itself, it also undoubtedly has the power of actually possessing all the perfections whose idea it contains within itself, that is, all those that I think of as existing in God. But if it is produced from some other cause, then I ask once again in the same way whether this cause comes from itself or from some other cause, until I finally reach a final cause, which will be God.

For it is clear enough that this questioning cannot produce an infinite regress, particularly because the issue I am dealing with here is a matter not only of the cause which once produced me but also—and most importantly—of the cause which preserves me at the present time.

And I cannot assume that perhaps a number of partial causes came together to produce me and that from one of them I received the idea of one of the perfections I attribute to God and from another the idea of another perfection, so that all those perfections are indeed found somewhere in the universe, but they are not all joined together in a single being who is God. Quite the contrary, [for] the unity and simplicity—or the inseparability of all those things present in God—is one of the principal perfections which I recognize in Him. And surely the idea of this unity of all His perfections could not have been placed in me by any cause from which I did not acquire ideas of the other perfections as well, for no single cause could have made it possible for me to understand that those perfections were joined together and inseparable, unless at the same time it enabled me to recognize what those perfections were.

And finally, as far as my parents are concerned, even if everything I have ever believed about them is true, it is still perfectly clear that they are not the ones who preserve me and that, to the extent that I am a thinking thing, there is no way they could have even made me. Instead they merely produced certain arrangements in the material substance which, as I have judged the matter, contains me—that is, contains my mind, for that is all I assume I am at the moment. And thus in this discussion there can be no difficulties with my parents. Given all this, however, from the mere fact that I exist and that the idea of a supremely perfect being, or God, is within me I must conclude that I have provided an extremely clear proof that God does, indeed, exist.

All that is left now is to examine how I have received that idea from God. For I have not derived it from the senses, and it has never come to me unexpectedly, as habitually occurs with the ideas of things I perceive with the senses, when those ideas of external substances impinge, or seem to impinge, on my sense organs. Nor is it something I just made up, for I am completely unable to remove anything from it or add anything to it. Thus, all that remains is that the idea is innate in me, just as the idea of myself is also innate in me.

And obviously it is not strange that God, when He created me, placed that idea within me, so that it would be, as it were, the mark of the master craftsman impressed in his own work, not that it is at all necessary for this mark to be different from the work itself. But from this one fact that God created me it is highly credible that He made me in some way in His image and likeness and that I perceive this likeness, which contains the idea of God, by the same faculty with which I perceive myself. In other words, when I turn my mind’s eye onto myself, I not only understand that I am an incomplete thing, dependent on something else, and one that aspires [constantly] to greater and better things without limit, but at the same time I also realize that the one I depend on contains within Himself all those greater things [to which I aspire], not merely indefinitely and potentially, but actually and infinitely, and thus that He is God. The entire force of my argument rests on the fact that I recognize I could not possibly exist with the sort of nature I possess, namely, having the idea of God within me, unless God truly existed as well—that God, I say, whose idea is in me, in other words, one having all those perfections which I do not understand but which I am somehow capable of contacting in my thoughts, and who is entirely free of any defect. These reasons are enough to show that He cannot be a deceiver, for natural light clearly demonstrates that every fraud and deception depends upon some defect.

But before I examine this matter more carefully and at the same time look into other truths I could derive from it, I wish to pause here for a while to contemplate God himself, to ponder His attributes, and to consider, admire, and adore the beauty of His immense light, to the extent that the eyes of my darkened intellect can bear it. For just as we believe through faith that the supreme happiness of our life hereafter consists only in this contemplation of the Divine Majesty, so we know from experience that the same [contemplation] now, though far less perfect, is the greatest joy we are capable of in this life.


In these last few days, I have grown accustomed to detaching my mind from my senses, and I have clearly noticed that, in fact, I perceive very little with any certainty about corporeal things and that I know a great deal more about the human mind and even more about God. As a result, I now have no difficulty directing my thoughts away from things I [perceive with the senses or] imagine and onto those purely intellectual matters divorced from all material substance. And clearly the idea I have of the human mind, to the extent that it is a thinking thing that has no extension in length, breadth, and depth and possesses nothing else which the body has, is much more distinct than my idea of any corporeal substance. Now, when I direct my attention to the fact that I have doubts, in other words, that [I am] something incomplete and dependent, the really clear and distinct idea of an independent and complete being, that is, of God, presents itself to me. From this one fact that there is an idea like this in me or else because of the fact that I, who possess this idea, exist, I draw the clear conclusion that God also exists and that my entire existence depends on Him every single moment [of my life]. Thus, I believe that the human intellect can know nothing with greater clarity and greater certainty. And now it seems to me I see a way by which I can go from this contemplation of the true God, in whom all the treasures of science and wisdom are hidden, to an understanding of everything else.

First of all, I recognize that it is impossible that God would ever deceive me, for in everything false or deceptive one discovers some sort of imperfection. And although it may appear that the ability to deceive is evidence of a certain acuity or power, the wish to deceive undoubtedly demonstrates either malice or mental weakness and is therefore not found in God.

Then, I know from experience that there is in me a certain faculty of judgment, which I certainly received from God, like all the other things within me. Since He is unwilling to deceive me, He obviously did not give me the kind of faculty that could ever lead me into error, if I used it correctly.

There would remain no doubt about this, if it did not seem to lead to the conclusion that I could never make mistakes. For if whatever is within me I have from God and if He did not give me any power to commit errors, it would appear that I could never make a mistake. Now, it is true that as long as I am thinking only about God and directing myself totally to Him, I detect no reason for errors or falsity. But after a while, when I turn back to myself, I know by experience that I am still subject to innumerable errors. When I seek out their cause, I notice that I can picture not only a certain real and positive [idea] of God, or of a supremely perfect being, but also, so to speak, a certain negative idea of nothingness, or of something removed as far as possible from every perfection, and [I recognize] that I am, as it were, something intermediate between God and nothingness, that is, I am situated between a supreme being and non-being in such a way that, insofar as I was created by a supreme being, there is, in fact, nothing in me which would deceive me or lead me into error, but insofar as I also participate, to a certain extent, in nothingness or non-being—in other words, given that I myself am not a supreme being—I lack a great many things. Therefore, it is not strange that I am deceived. From this I understand that error, to the extent that it is error, is not something real which depends on God, but is merely a defect. Thus, for me to fall into error, it is not necessary that I have been given a specific power to do this by God. Instead, I happen to make mistakes because the power I have of judging what is true [and what is false], which I do have from God, is not infinite within me.

However, this is not yet entirely satisfactory, for error is not pure negation, but rather the privation or lack of a certain knowledge that somehow ought to be within me. But to anyone who thinks about the nature of God, it does not seem possible that He would place within me any power that is not a perfect example of its kind or that lacks some perfection it ought to have. For [if it is true] that the greater the skill of the craftsman, the more perfect the works he produces, what could the supreme maker of all things create which was not perfect in all its parts? And there is no doubt that God could have created me in such a way that I was never deceived, and, similarly, there is no doubt that He always wills what is best. So then, is it better for me to make mistakes or not to make them?

As I weigh these matters more attentively, it occurs to me, first, that I should not find it strange if I do not understand the reasons for some of the things God does, and thus I should not entertain doubts about His existence just because I happen to learn from experience about certain other things and do not grasp why or how He has created them. For given the fact that I already know my nature is extremely infirm and limited and that, by contrast, the nature of God is immense, incomprehensible, and infinite, I understand sufficiently well that He is capable of innumerable things about whose causes I am ignorant. For that reason alone, I believe that the entire class of causes we are in the habit of searching out as final causes is completely useless in matters of physics, for I do not think I am capable of investigating the final purposes of God without appearing foolhardy.(25)

It also occurs to me that, whenever we look into whether the works of God are perfect, we should not examine one particular creature by itself, but rather the universal totality of things. For something which may well appear very imperfect, and not unjustly so, if it is by itself, is utterly perfect [if we think of it] as part of the [entire] universe. And although, given my wish to doubt everything, I have up to now recognized nothing as certain, other than the existence of myself and God, nonetheless, since I have observed the immense power of God, I cannot deny that He may have created many other things or at least is capable of creating them and therefore that I may occupy a place in a universe of things.(26)

After that, by examining myself more closely and looking into the nature of my errors (the only things testifying to some imperfection in me), I observe that they proceed from two causes working together simultaneously, namely, from the faculty of knowing, which I possess, and from the faculty of choosing, or from my freedom to choose, in other words from both the intellect and the will together. For through my intellect alone I [do not affirm or deny anything, but] simply grasp the ideas of things about which I can make a judgment, and, if I consider my intellect in precisely this way, I find nothing there which is, strictly speaking, an error. For although countless things may well exist of which I have no idea at all within me, I still should not assert that I am deprived of them, in the proper sense of that word, [as if that knowledge were something my understanding was entitled to thanks to its nature]. I can only make the negative claim that I do not have them, for obviously I can produce no reason which enables me to prove that God ought to have given me a greater power of understanding than He has provided. And although I know that a craftsman is an expert, still I do not assume that he must therefore place in each of his works all the perfections he is capable of placing in some. Moreover, I certainly cannot complain that I have received from God a will or a freedom to choose that is insufficiently ample and perfect. For I clearly know from experience that my will is not circumscribed by any limits. And what seems to me particularly worthy of notice is the fact that, apart from my will, there is nothing in me so perfect or so great that I do not recognize that it could be still more perfect or even greater. For, to consider an example: if I think about the power of understanding, I see at once that in me it is very small and extremely limited. At the same time, I form an idea of another understanding which is much greater, even totally great and infinite, and from the mere fact that I can form this idea, I see that it pertains to the nature of God. By the same reasoning, if I examine my faculty of memory or of imagination or any other faculty, I find none at all which I do not recognize as tenuous and confined in me and immense in God. It is only my will or my freedom to choose which I experience as so great in me that I do not apprehend the idea of anything greater. Thus, through my will, more than through anything else, I understand that I bear a certain image of and resemblance to God. For although the will is incomparably greater in God than in myself, because the knowledge and power linked to it make it much stronger and more efficacious and because, with respect to its object, His will extends to more things, nonetheless, if I think of the will formally and precisely in and of itself, His does not appear greater than mine. For the power of will consists only in the ability to do or not to do [something] (that is, to affirm or to deny, to follow or to avoid) or rather in this one thing alone, that whether we affirm or deny, follow or avoid [something] which our understanding has set before us, we act in such a way that we do not feel that any external force is determining what we do. For to be free, I do not have to be inclined in two [different] directions. On the contrary, the more I am inclined to one—whether that is because I understand that the principle of the true and the good are manifestly in it or because that is the way God has arranged the inner core of my thinking—the more freely I choose it. Clearly divine grace and natural knowledge never diminish liberty, but rather increase and strengthen it. However, the indifference I experience when there is no reason urging me to one side more than to the other is the lowest degree of liberty. It does not demonstrate any perfection in [the will], but rather a defect in my understanding or else a certain negation. For if I always clearly perceived what is true and good, I would never need to deliberate about what I ought to be judging or choosing, and thus, although I would be entirely free, I could never be indifferent.

For these reasons, however, I perceive that the power of willing, which I have from God, considered in itself, is not the source of my errors. For it is extremely spacious and a perfect example of its kind. And the source is not my power of understanding. For when I understand something, I undoubtedly do so correctly, since my [power of] understanding comes from God, and thus it is impossible for it to deceive me. So from where do my errors arise? Surely from the single fact that my will ranges more widely than my intellect, and I do not keep it within the same limits but extend it even to those things which I do not understand. Since the will does not discriminate among these things, it easily turns away from the true and the good, and, in this way, I make mistakes and transgress.

For example, in the past few days, when I was examining whether anything in the world existed and I observed that, from the very fact that I was exploring this [question], it clearly followed that I existed, I was not able [to prevent myself] from judging that what I understood so clearly was true, not because I was forced to that conclusion by any external force, but because a great light in my understanding was followed by a great inclination in my will, and thus the less I was indifferent to the issue, the more spontaneous and free was my belief. However, now not only do I know that I exist, to the extent I am a thinking thing, but also, beyond that, a certain idea of corporeal nature has revealed itself to me, and, as it so happens, I am in doubt whether the thinking nature which is within me, or rather, which I myself am, is something different from that corporeal nature or whether both of them are the same, and I assume that up to this point no reason has offered itself to my understanding which might convince me of one rather than the other. From this single fact it is clear that I am indifferent as to which of the two I should affirm or deny, or whether I should even make any judgment in the matter.

Furthermore, this indifference extends not merely to those things about which the understanding knows nothing at all, but also, in general, to everything which it does not recognize with sufficient clarity at the time when the will is deliberating about them. For, however probable the conjectures [may be] which draw me in one direction, the mere knowledge that they are only conjectures and not certain and indubitable reasons is enough to urge me to assent to the opposite view. In the past few days I have learned this well enough by experience, once I assumed that all those things I had previously accepted as absolutely true were utterly false, because of the single fact that I discovered they could in some way be doubted.

But when I do not perceive that something is true with sufficient clarity and distinctness, if, in fact, I abstain from rendering judgment, I am obviously acting correctly and am not deceived. But if at that time I affirm or deny, [then] I am not using my freedom to choose properly. And if I change my mind [and affirm] something false, then, of course I will be deceived. However, if I embrace the alternative, then I may, indeed, hit upon the truth by chance, but that would not free me from blame, since natural light makes it clear that a perception of the understanding must always precede a determination of the will. And it is in this incorrect use of the freedom of the will that one finds the privation which constitutes the nature of error. Privation, I say, inheres in this act of the will, to the extent that it proceeds from me, but not in the faculty I have received from God, nor even in the act, insofar as it depends upon Him.

For I have no cause to complain at all about the fact that God has not given me a greater power of understanding or a more powerful natural light than He has, because it is in the nature of a finite intellect not to understand many things and it is in the nature of a created intellect to be finite. Instead, I should thank Him, who has never owed me anything, for His generosity, rather than thinking that He has deprived me of something He did not provide or else has taken it away.

And I also have no reason to complain on the ground that He gave me a will more extensive than my understanding. For since the will consists of only a single thing and is, so to speak, indivisible, it does not seem that its nature is such that anything could be removed [without destroying it]. And, of course, the more extensive my will, the more I ought to show gratitude to the one who gave it to me.

And finally I also ought not to complain because God concurs with me in bringing out those acts of will or those judgments in which I am deceived. For those actions are true and good in every way, to the extent that they depend on God, and in a certain way there is more perfection in me because I am capable of eliciting these actions than if I were not. But privation, in which one finds the only formal reason for falsity and failure, has no need of God’s concurrence, because it is not a thing, and if one links it to Him as its cause, one should not call it privation but merely negation. For obviously it is not an imperfection in God that He has given me freedom to assent or not to assent to certain things, when He has not placed a clear and distinct perception of them in my understanding. However, it is undoubtedly an imperfection in me that I do not use that liberty well and that I bring my judgment to bear on things which I do not properly understand. Nonetheless, I see that God could easily have created me so that I never made mistakes, even though I remained free and had a limited understanding. For example, He could have placed in my intellect a clear and distinct perception of everything about which I would ever deliberate, or He could have impressed on my memory that I should never make judgments about things which I did not understand clearly and distinctly, and done that so firmly that it would be impossible for me ever to forget. And I readily understand that, if God had made me that way, insofar as I have an idea of this totality, I would have been more perfect than I am now. But I cannot therefore deny that there may somehow be more perfection in this whole universe of things because some of its parts are not immune to errors and others are, than if all things were entirely alike. And I have no right to complain just because the part God wanted me to play in the universe is not the most important and most perfect of all.

Besides, even if I am unable to avoid errors in the first way [mentioned above], which depends upon a clear perception of all those things about which I need to deliberate, I can still use that other [method], which requires me only to remember to abstain from rendering judgment every time the truth of something is not evident. For although experience teaches me that I have a weakness which renders me incapable of keeping [my mind] always focused on one and the same thought, I can still see to it that by attentive and frequently repeated mediation I remember that fact every time the occasion demands. In this way I will acquire the habit of not making mistakes.

Since the greatest and preeminent perfection of human beings consists in this ability to avoid mistakes, I think that with the discovery in today’s meditation of the cause of error and falsity I have gained a not inconsiderable gift. Clearly that cause can be nothing other than what I have identified. For as long as I keep my will restrained when I deliver judgments, so that it extends itself only to those things which reveal themselves clearly and distinctly to my understanding, I will surely be incapable of making mistakes, because every clear and distinct perception is undoubtedly something [real]. Therefore, it cannot exist from nothing but necessarily has God as its author—God, I say, that supremely perfect being, who would contradict His nature if He were deceitful. And thus, [such a perception] is unquestionably true. I have learned today not only what I must avoid in order to ensure that I am never deceived, but also at the same time what I must do in order to reach the truth. For I will assuredly reach that if I only pay sufficient attention to all the things I understand perfectly and distinguish these from all the other things which I apprehend confusedly and obscurely. In future, I will pay careful attention to this matter.


Many other [issues] concerning the attributes of God are still left for me to examine, [as well as] many things about myself, that is, about the nature of my mind. However, I will perhaps return to those at another time. Now (after I have taken note of what I must avoid and what I must do to arrive at the truth) nothing seems to be more pressing than for me to attempt to emerge from the doubts into which I have fallen in the last few days and to see whether I can know anything certain about material things.

But before I look into whether any such substances exist outside of me, I ought to consider the ideas of them, insofar as they are in my thinking, and see which of them are distinct and which confused.

For example, I distinctly imagine quantity, which philosophers commonly refer to as continuous, that is, the extent of the length, breadth and depth in this quantity, or rather in the object being quantified. I enumerate the various parts of the object, and assign to those parts all sorts of sizes, shapes, locations, and local movements, and to those movements all sorts of durations.

And in this way I not only clearly observe and acquire knowledge of those things when I examine them in general, but later, by devoting my attention to them, I also perceive innumerable particular details about their shapes, number, motion, and so on, whose truth is so evident and so well suited to my nature, that when I discover them for the first time, it does not seem as if I am learning anything new so much as remembering what I already used to know about them before, or else noticing for the first time things which were truly within me earlier, although I had not previously directed my mental gaze on them.

And here I believe that the most important issue for me to consider is that I find within me countless ideas of certain things which, even if they perhaps do not exist outside of me at all, still cannot be called nothing. Although in a certain sense I can think of them whenever I wish, still I do not create them. They have their own true and immutable natures. For example, when I imagine a triangle whose particular shape perhaps does not exist and has never existed outside my thinking, it nevertheless has, in fact, a certain determinate nature or essence or form which is immutable and eternal, which I did not produce, and which does not depend upon my mind, as is clear enough from the fact that I can demonstrate the various properties of that triangle, namely, that the sum of its three angles is equal to two right angles, that its longest side subtends its largest angle, and so on. These properties I now recognize clearly whether I wish to or not, although earlier, when I imagined the triangle [for the first time], I was not thinking of them at all and therefore did not invent them.

In this case it is irrelevant if I tell [myself] that perhaps this idea of a triangle came to me from external things through my sense organs, on the ground that I have certainly now and then seen objects possessing a triangular shape. For I am able to think up countless other shapes about which there can be no suspicion that they ever flowed into me through my senses, and yet [I can] demonstrate various properties about them, no less than I can about the triangle, all of which are manifestly true, since I clearly conceive of them, and thus they are something and not pure nothingness. For it is evident that everything which is true is something, and I have already shown in great detail [above] that all those things I clearly conceive are true. Besides, even if I had not proved this, the nature of my mind is certainly such that I cannot refuse to assent to them, at least for as long as I am perceiving them clearly. And I remember that, even in those earlier days, when I was attracted as strongly as possible to objects of sense experience, I always maintained that the most certain things of all were those kinds of truth which I recognized clearly as shapes, numbers, or other things pertinent to arithmetic or geometry or to pure and abstract mathematics generally.

But if from the mere fact that I can draw the idea of some object from my thinking it now follows that all things which I perceive clearly and distinctly as pertaining to that object really do belong to it, can I not also derive from this an argument which proves that God exists? For clearly I find the idea of Him, that is, of a supremely perfect being, within me just as much as I do the idea of some shape or number. I know that [actual and] eternal existence belongs to His nature just as clearly and distinctly as [I know] that what I prove about some shape or number also belongs to the nature of that shape or number. And therefore, even if all the things I have meditated on in the preceding days were not true, for me the existence of God ought to have at least the same degree of certainty as [I have recognized] up to this point in the truths of mathematics.

At first glance, however, this argument does not look entirely logical but [appears to] contain some sort of sophistry. For, since in all other matters I have been accustomed to distinguish existence from essence, I can easily persuade myself that [existence] can also be separated from the essence of God and thus that I [can] think of God as not actually existing. However, when I think about this more carefully, it becomes clear that one can no more separate existence from the essence of God, than one can separate the fact that the sum of the three angles in a triangle is equal to two right angles from the essence of a triangle or the idea of a valley from the idea of a mountain. Thus, it is no less contradictory to think of a God (that is, of a supremely perfect being) who lacks existence (that is, who lacks a certain perfection) than it is to think of a mountain without a valley.

Nonetheless, although I cannot conceive of God other than as something with existence, any more than I can of a mountain without a valley, the truth is that just because I think of a mountain with a valley, it does not therefore follow that there is any mountain in the world. In the same way, just because I think of God as having existence, it does not seem to follow that God therefore exists. For my thinking imposes no necessity on things, and in the same way as I can imagine a horse with wings, even though no horse has wings, so I could perhaps attribute existence to God, even though no God exists.

But this [objection] conceals a fallacy. For from the fact that I cannot think of a mountain without a valley, it does not follow that a mountain and valley exist anywhere, but merely that the mountain and valley, whether they exist or not, cannot be separated from each other. However, from the fact that I cannot think of God without existence, it does follow that existence is inseparable from God, and thus that He truly does exist. Not that my thought brings this about or imposes any necessity on anything, but rather, by contrast, because the necessity of the thing itself, that is, of the existence of God, determines that I must think this way. For I am not free to think of God without existence (that is, of a supremely perfect being lacking a supreme perfection) in the same way that I am free to imagine a horse with wings or without them.

Nor should anyone claim here that it is, in fact, necessary for me to admit that God exists, once I have assumed that He has every perfection, since existence is one of these, but that my first assumption was unnecessary, just as it is unnecessary for me to claim that all quadrilaterals [can] be inscribed in a circle. For supposing I believed this, I would have to concede that a rhombus [could] be inscribed in a circle, an assertion which is, however, clearly false. For although it may not be necessary for me ever to entertain any thought of God, nevertheless, whenever I do happen to think of a first and supreme being, and, as it were, to derive an idea of Him from the storehouse of my mind, I have to attribute to Him all perfections, even though I do not enumerate them all at that time or attend to each one of them individually. And this necessity is obviously sufficient to make me conclude correctly, once I have recognized that existence is a perfection, that a first and supreme being exists. In the same way, it is not necessary that I ever imagine any triangle, but every time I wish to consider a rectilinear figure with only three angles, I have to attribute to it those [properties] from which I correctly infer that its three angles are no greater than two right angles, although at that time I may not notice this. But when I think about which figures [are capable of being] inscribed in a circle, it is not at all necessary that I believe every quadrilateral is included in their number. On the contrary, I cannot even imagine anything like that, as long as I do not wish to admit anything unless I understand it clearly and distinctly. Thus, there is a great difference between false assumptions of this kind and the true ideas born within me, of which the first and most important is the idea of God. For, in fact, I understand in many ways that this [idea] is not something made up which depends upon my thought but [is] the image of a true and immutable nature: first, because I cannot think of any other thing to whose essence existence [necessarily] pertains, other than God alone; second, because I am unable to conceive of two or more Gods of this sort and because, given that I have already assumed that one God exists, I see clearly that it is necessary that He has previously existed from [all] eternity and will continue [to exist] for all eternity; and finally because I perceive many other things in God, none of which I can remove or change.

But, in fact, no matter what reasoning I finally use by way of proof, I always come back to the point that the only things I find entirely persuasive are those I perceive clearly and distinctly. And although among the things I perceive in this way, some are obvious to everyone, while others reveal themselves only to those who look into them more closely and investigate more diligently, nonetheless once the latter have been discovered, they are considered no less certain than the former. For example, even though in a right-angled triangle it is not so readily apparent that the square of the base is equal to the squares of the [other two] sides, as [it is that] the base subtends the greatest angle, nonetheless, after we have recognized this for the first time, we are no less certain of its truth [than we are of the other]. But where God is concerned, if I were not overwhelmed with prejudices and if images of sensible things were not laying siege to my thinking from every quarter, there is certainly nothing I would recognize sooner or more easily than Him. For what is more inherently evident than that there is a supreme being, in other words, that God exists, for existence [necessarily and eternally] belongs to His essence alone?

And although it required careful reflection on my part to perceive this [truth], nonetheless I am now not only as sure about it as I am about all the other things which seem [to me] most certain, but also, beyond that, I see that the certainty of everything else is so dependent on this very truth that without it nothing could ever be perfectly known.

For although my nature is such that, as long as I perceive something really clearly and distinctly, I am unable to deny that it is true, nevertheless, because I am also by nature incapable of always fixing my mental gaze on the same thing in order to perceive it clearly, [and because] my memory may often return to a judgment I have previously made at a time when I am not paying full attention to the reasons why I made such a judgment, other arguments can present themselves which, if I knew nothing about God, might easily drive me to abandon that opinion. Thus, I would never have any true and certain knowledge, but merely vague and changeable opinions. For example, when I consider the nature of a triangle, it is, in fact, very evident to me, given that I am well versed in the principles of geometry, that its three angles are equal to two right angles, and, as long as I focus on the proof of this fact, it is impossible for me not to believe that it is true. But as soon as I turn my mental gaze away from that, although I still remember I perceived it very clearly, it could still easily happen that I doubt whether it is true, if, in fact, I had no knowledge of God. For I can convince myself that nature created me in such a way that I am sometimes deceived by those things I think I perceive as clearly as possible, especially when I remember that I have often considered many things true and certain that I later judged to be false, once other reasons had persuaded me.

However, after I perceived that God exists, because at the same time I also realized that all other things depend on Him and that He is not a deceiver, I therefore concluded that everything I perceive clearly and distinctly is necessarily true. Thus, even if I am not fully attending to the reasons why I have judged that something is true, if I only remember that I have perceived it clearly and distinctly, no opposing argument can present itself that would force me to have doubts. Instead, I possess true and certain knowledge about it—and not just about that, but about all other matters which I remember having demonstrated at any time, for example, [about the truths] of geometry and the like. For what argument could I now bring against them? What about the fact that I am created in such a manner that I often make mistakes? But now I know that I cannot be deceived about those things which I understand clearly. What about the fact that I used to consider many other things true and certain which I later discovered to be false? But I was not perceiving any of these [things] clearly and distinctly, and, in my ignorance of this rule [for confirming] the truth, I happened to believe them for other reasons which I later discovered to be less firm. What then will I say? Perhaps I am dreaming (an objection I recently made to myself), or else everything I am now thinking is no more true than what happens when I am asleep? But even this does not change anything: for surely even though I am asleep, if what is in my intellect is clear, then it is absolutely true.

In this way I fully recognize that all certainty and truth in science depend only on a knowledge of the true God, so much so that, before I knew Him, I could have no perfect knowledge of anything else. But now I am able to understand innumerable things completely and clearly, about both God Himself and other intellectual matters, as well as about all those things in corporeal nature that are objects of study in pure mathematics.


It remains for me to examine whether material things exist. At the moment, I do, in fact, know that they can exist, at least to the extent that they are objects of pure mathematics, since I perceive them clearly and distinctly. For there is no doubt that God is capable of producing everything which I am capable of perceiving in this way, and I have never judged that there is anything He cannot create, except in those cases where there might be a contradiction in my clear perception of it. Moreover, from my faculty of imagination, which I have learned by experience I use when I turn my attention to material substances, it seems to follow that they exist. For when I consider carefully what the imagination is, it seems nothing other than a certain application of my cognitive faculty to an object which is immediately present to it and which therefore exists.

In order to clarify this matter fully, I will first examine the difference between imagination and pure intellection. For example, when I imagine a triangle, not only do I understand that it is a shape composed of three lines, but at the same time I also see those three lines as if they were, so to speak, present to my mind’s eye. This is what I call imagining. However, if I wish to think about a chiliagon, even though I understand that it is a figure consisting of one thousand sides just as well as I understand that a triangle is a figure consisting of three sides, I do not imagine those thousand sides in the same way, nor do I see [them], as it were, in front of me. And although, thanks to my habit of always imagining something whenever I think of a corporeal substance, it may happen that [in thinking of a chiliagon] I create for myself a confused picture of some shape, nevertheless, it is obviously not a chiliagon, because it is no different from the shape I would also picture to myself if I were thinking of a myriagon or of any other figure with many sides.(27) And that shape is no help at all in recognizing those properties which distinguish the chiliagon from other polygons. However, if it is a question of a pentagon, I can certainly understand its shape just as [well as] I can the shape of a chiliagon, without the assistance of my imagination, but, of course, I can also imagine the pentagon by applying my mind’s eye to its five sides and to the area they contain. From this I clearly recognize that, in order to imagine things, I need a certain special mental effort that I do not use to understand them, and this new mental effort reveals clearly the difference between imagination and pure understanding.

Furthermore, I notice that this power of imagining, which exists within me, insofar as it differs from the power of understanding, is not a necessary part of my own essence, that is, of my mind. For even if I did not have it, I would still undoubtedly remain the same person I am now. From this it would seem to follow that my imagination depends upon something different from [my mind]. I understand easily enough that if a certain body exists to which my mind is joined in such a way that whenever my mind so wishes, it can direct itself, so to speak, to examining it, then it would be possible, thanks to this particular body, for me to imagine corporeal things.(28) Thus, the only difference between this mode of thinking and pure understanding would be that the mind, while it is understanding, in some way turns its attention onto itself and considers one of the ideas present in itself, but when it is imagining, it turns its attention to the body and sees something in it which conforms to an idea which it has either conceived by itself or perceived with the senses. I readily understand, I say, that the imagination could be formed in this way, if the body exists, and because no other equally convenient way of explaining it comes to mind, I infer from this that the body probably exists—but only probably—and although I am looking into everything carefully, I still do not yet see how from this distinct idea of corporeal nature which I find in my imagination I can derive any argument which necessarily concludes that anything corporeal exists.

However, I am in the habit of imagining many things apart from the corporeal nature which is the object of study in pure mathematics, such as colours, sounds, smells, pain, and things like that, although not so distinctly. And since I perceive these better with my senses, through which, with the help of my memory, they appear to have reached my imagination, then in order to deal with them in a more appropriate manner, I ought to consider the senses at the same time as well and see whether those things which I perceive by this method of thinking, which I call sensation, will enable me to establish some credible argument to prove the existence of corporeal things.

First of all, I will review in my mind the things that I previously believed to be true, because I perceived them with my senses, along with the reasons for those beliefs. Then I will also assess the reasons why I later called them into doubt. And finally I will consider what I ought to believe about them now.

To begin with, then, I sensed that I had a head, hands, feet, and other limbs making up that body which I looked on as if it were a part of me or perhaps even my totality. I sensed that this body moved around among many other bodies which could affect it in different ways, either agreeably or disagreeably. I judged which ones were agreeable by a certain feeling of pleasure and which ones were disagreeable by a feeling of pain. Apart from pain and pleasure, I also felt inside me sensations of hunger, thirst, and other appetites of this kind, as well as certain physical inclinations towards joy, sadness, anger, and other similar emotions. And outside myself, besides the extension, shapes, and motions of bodies, I also had sensations in them of hardness, heat, and other tactile qualities and, beyond that, of light, colours, smells, tastes, and sounds. From the variety of these, I distinguished sky, land, sea, and other bodies, one after another. And because of the ideas of all those qualities which presented themselves to my thinking and which I kept sensing as merely my own personal and immediate ideas, I reasonably believed that I was perceiving certain objects entirely different from my thinking, that is, bodies from which these ideas proceeded. For experience taught me that these ideas reached me without my consent, so that I was unable to sense any object, even if I wanted to, unless it was present to my organs of sense, and I was unable not to sense it when it was present. And since the ideas I perceived with my senses were much more vivid and expressive and even, in their own way, more distinct than any of those which I myself intentionally and deliberately shaped by meditation or which I noticed impressed on my memory, it did not seem possible that they could have proceeded from myself. Thus, the only conclusion left was that they had come from some other things. Because I had no conception of these objects other than what I derived from those ideas themselves, the only thought my mind could entertain was that [the objects] were similar to [the ideas they produced]. And since I also remembered that earlier I had used my senses rather than my reason and realized that the ideas which I myself formed were not as expressive as those which I perceived with my senses and that most of the former were composed of parts of the latter, I easily convinced myself that I had nothing at all in my intellect which I had not previously had in my senses. I also maintained, not without reason, that this body, which, by some special right, I called my own, belonged to me more than any other object, for I could never separate myself from it, as I could from other [bodies], I felt every appetite and emotion in it and because of it, and finally, I noticed pain and the titillation of pleasure in its parts, but not in any objects placed outside it. But why a certain strange sadness of spirit follows a sensation of pain and a certain joy follows from a sensation of [pleasurable] titillation, or why some sort of twitching in the stomach, which I call hunger, is urging me to eat food, while the dryness of my throat [is urging me] to drink, and so on—for that I had no logical explanation, other than that these were things I had learned from nature. For there is clearly no relationship (at least, none I can understand) between that twitching [in the stomach] and the desire to consume food, or between the sensation of something causing pain and the awareness of sorrow arising from that feeling. But it seemed to me that all the other judgments I made about objects of sense experience I had learned from nature. For I had convinced myself that that was how things happened, before I thought about any arguments which might prove it.

However, many later experiences have gradually weakened the entire faith I used to have in the senses. For now and then towers which seemed round from a distance appeared square from near at hand, immense statues standing on the tower summits did not seem large when I viewed them from the ground, and in countless other cases like these I discovered that my judgments were deceived in matters dealing with external senses. And not just with external [senses], but also with internal ones as well. For what could be more internal than pain? And yet I heard that people whose legs or arms had been cut off sometimes still seemed to feel pain in the part of their body which they lacked. Thus, even though I were to feel pain in one of my limbs, I did not think I could be completely certain that it was the limb which caused my pain. To these reasons for doubting sense experience, I recently added two extremely general ones. First, there was nothing I ever thought I was sensing while awake that I could not also think I was sensing now and then while asleep, and since I do not believe that those things I appear to sense in my sleep come to me from objects placed outside me, I did not see why I should give more credit to those I appear to sense when I am awake. Second, because I was still ignorant—or at least was assuming I was ignorant—of the author of my being, there seemed to be nothing to prevent nature from constituting me in such a way that I would make mistakes, even in those matters which seemed to me most true. And as far as concerns the reasons which had previously convinced me of the truth of what I apprehended with my senses, I had no difficulty answering them. For since nature seemed to push me to accept many things which my reason opposed, I believed I should not place much trust in those things nature taught. And although perceptions of the senses did not depend upon my will, I did not believe that was reason enough for me to conclude that they must come from things different from myself, because there could well be some other faculty in me, even one I did not yet know, which produced them.

But now that I am starting to gain a better understanding of myself and of the author of my being, I do not, in fact, believe that I should  rashly accept all those things I appear to possess from my senses, but, at the same time, [I do not think] I should call everything into doubt.

First, since I know that all those things I understand clearly and distinctly could have been created by God in a way that matches my conception of them, the fact that I can clearly and distinctly understand one thing apart from something else is sufficient to convince me that the two of them are different, because they can be separated from each other, at least by God. The power by which this [separation] takes place is irrelevant to my judgment that they are distinct. And therefore, given the mere fact that I know I exist and that, at the moment, I look upon my nature or essence as absolutely nothing other than that I am a thinking thing, I reasonably conclude that my essence consists of this single fact: I am a thinking thing. And although I may well possess (or rather, as I will state later, although I certainly do possess) a body which is very closely joined to me, nonetheless, because, on the one hand, I have a clear and distinct idea of myself, insofar as I am merely a thinking thing, without extension, and, on the other hand, [I have] a distinct idea of body, insofar as it is merely an extended thing which does not think, it is certain that my mind is completely distinct from my body and can exist without it.

Moreover, I discover in myself faculties for certain special forms of thinking, namely, the faculties of imagining and feeling. I can conceive of myself clearly and distinctly as a complete being without these, but I cannot do the reverse and think of these faculties without me, that is, without an intelligent substance to which they belong. For the formal conception of them includes some act of intellection by which I perceive that they are different from me, just as [shapes, movement, and the other] modes [or accidents of bodies are different] from the object [to which they belong]. I also recognize certain other faculties [in me], like changing position, assuming various postures, and so on, which certainly cannot be conceived, any more than those previously mentioned, apart from some substance to which they belong, and therefore they, too, cannot exist without it. However, it is evident that these [faculties], if indeed they [truly] exist, must belong to some corporeal or extended substance, and not to any intelligent substance, since the clear and distinct conception of them obviously contains some [form of] extension, but no intellectual activity whatsoever. Now, it is, in fact, true that I do have a certain passive faculty of perception, that is, of receiving and recognizing ideas of sensible things. But I would be unable to use this power unless some active faculty existed, as well, either in me or in some other substance capable of producing or forming these ideas.(29) But this [active faculty] clearly cannot exist within me, because it presupposes no intellectual activity at all and because, without my cooperation and often even against my will, it produces those ideas. Therefore I am left to conclude that it exists in some substance different from me that must contain, either formally or eminently, all the reality objectively present in the ideas produced by that faculty (as I have just observed above). This substance is either a body, that is, something with a corporeal nature which obviously contains formally everything objectively present in the ideas, or it must be God, or some other creature nobler than the body, one that contains [those same things] eminently. But since God is not a deceiver, it is very evident that He does not transmit these ideas to me from Himself directly or even through the intervention of some other creature in which their objective reality is contained, not formally but only eminently. For since He has given me no faculty whatsoever for recognizing such a source, but by contrast, has endowed me with a powerful tendency to believe that these ideas are sent out from corporeal things, I do not see how it would be possible not to think of Him as a deceiver, if these [ideas] were sent from any source other than corporeal things. And therefore corporeal things exist. However, perhaps they do not all exist precisely in the ways I grasp them with my senses, since what I comprehend with my senses is very obscure and confused in many things. But at least [I should accept as true] all those things in them which I understand clearly and distinctly, that is, generally speaking, everything which is included as an object in pure mathematics.(30)

But as far as concerns other material things which are either merely particular, like that the sun is of such and such a magnitude and shape, and so on, or less clearly understood, like light, sound, pain, and things like that, although these may be extremely doubtful and uncertain, nonetheless, because of the very fact that God is not a deceiver and thus it is impossible for there to be any falsity in my opinions which I cannot correct with another faculty God has given me, I have the sure hope that I can reach the truth even in these matters. And clearly there is no doubt that all those things I learn from nature contain some truth. For by the termnature, generally speaking, I understand nothing other than either God himself or the coordinated structure of created things established by God, and by the term my nature, in particular, nothing other than the combination of all those things I have been endowed with by God.

However, there is nothing that nature teaches me more emphatically than the fact that I have a body, which does badly when I feel pain, which needs food or drink when I suffer from hunger or thirst, and so on. And therefore I should not doubt that there is some truth in this.

For through these feelings of pain, hunger, thirst, and so on, nature teaches me that I am not only present in my body in the same way a sailor is present onboard a ship, but also that I am bound up very closely and, so to speak, mixed in with it, so that my body and I form a certain unity.(31) For if that were not the case, then when my body was injured, I, who am merely a thinking thing, would not feel any pain because of it; instead, I would perceive the wound purely with my intellect, just as a sailor notices with his eyes if something is broken on his ship. And when my body needed food or drink, I would understand that clearly and not have confused feelings of hunger and thirst. For those sensations of thirst, hunger, pain, and so on are really nothing other than certain confused ways of thinking, which arise from the union and, as it were, the mixture of the mind with the body.

Moreover, nature also teaches me that various other bodies exist around my own and that I should pursue some of these and stay away from others. And certainly from the fact that I sense a wide diversity of colours, sounds, odours, tastes, heat, hardness, and similar things, I reasonably conclude that in the bodies from which these different sense perceptions come there are certain variations which correspond to these perceptions, even if they are perhaps not like them. And given the fact that I find some of these sense perceptions pleasant and others unpleasant, it is entirely certain that my body, or rather my totality, since I am composed of body and mind, can be affected by various agreeable and disagreeable bodies surrounding it.

However, many other things which I seemed to have learned from nature I have not really received from her, but rather from a certain habit I have of accepting careless judgments [about things]. And thus it could easily be the case that these judgments are false—for example, [the opinion I have] that all space in which nothing at all happens to stimulate my senses is a vacuum, that in a warm substance there is something completely similar to the idea of heat which is in me, that in a white or green [substance] there is the same whiteness or greenness which I sense, that in [something] bitter or sweet there is the same taste I sense, and so on, that stars and towers and anything else some distance away have bodies with the same size and shape as the ones they present to my senses, and things of that sort. But in order to ensure that what I perceive in this matter is sufficiently distinct, I should define more accurately what it is precisely that I mean when I say I have learned something from nature. For here I am taking the word nature in a more restricted sense than the combination of all those things which have been bestowed on me by God. For this combination contains many things which pertain only to the mind, such as the fact that I perceive what has been done cannot be undone, and all the other things I grasp by my natural light [without the help of the body]. Such things are not under discussion here. This combination also refers to many things which concern only the body, like its tendency to move downward, and so on, which I am also not dealing with [here]. Instead, I am considering only those things which God has given me as a combination of mind and body.32

And so nature, in this sense, certainly teaches me to avoid those things which bring a sensation of pain and to pursue those which [bring] a sensation of pleasure, and such like, but, beyond that, it is not clear that with those sense perceptions nature teaches us that we can conclude anything about things placed outside of us without a previous examination by the understanding, because to know the truth about them seems to belong only to the mind and not to that combination [of body and mind]. And so, although a star does not make an impression on my eyes any greater than the flame of a small candle, nonetheless, that fact does not incline me, in any real or positive way, to believe that the star is not larger [than the flame], but from the time of my youth I have made this judgment without any reason [to support it]. And although I feel heat when I come near the fire, and even pain if I get too close to it, that is really no reason to believe that there is something in the fire similar to that heat I feel any more than there is something similar to the pain. The only thing [I can conclude] is that there is something in the fire, whatever it might be, which brings out in us those sensations of heat or pain. So, too, although in some space there is nothing which stimulates my senses, it does not therefore follow that the space contains no substances. But I see that in these and in a great many other matters, I have grown accustomed to undermine the order of nature, because, of course, these sense perceptions are, strictly speaking, given to me by nature merely to indicate to my mind which things are agreeable or disagreeable to that combination of which it is a part, and for that purpose they are sufficiently clear and distinct. But then I use them as if they were dependable rules for immediately recognizing the essence of bodies placed outside me. However, about such bodies they reveal nothing except what is confusing and obscure.

In an earlier section, I have already examined sufficiently why my judgments happen to be defective, in spite of the goodness of God. However, a new difficulty crops up here concerning those very things which nature reveals to me as objects I should seek out or avoid and also concerning the internal sensations, in which I appear to have discovered errors: for example, when someone, deceived by the pleasant taste of a certain food, eats a poison hidden within it [and thus makes a mistake]. Of course, in this situation, the person’s nature urges him only to eat food which has a pleasant taste and not the poison, of which he has no knowledge at all. And from this, the only conclusion I can draw is that my nature does not know everything. There is nothing astonishing about that, because a human being is a finite substance and thus is capable of only limited perfection.

However, we are not infrequently wrong even in those things which nature urges [us to seek]. For example, sick people are eager for drink or food which will harm them soon afterwards. One could perhaps claim that such people make mistakes because their nature has been corrupted. But this does not remove the difficulty, for a sick person is no less a true creature of God than a healthy one, and thus it seems no less contradictory that God has given the person a deceitful nature. And just as a clock made out of wheels and weights observes all the laws of nature with the same accuracy when it is badly made and does not indicate the hours correctly as it does when it completely satisfies the wishes of the person who made it, in the same way, if I look on the human body as some kind of machine composed of bones, nerves, muscles, veins, blood, and skin, as if no mind existed in it, the body would still have all the same motions it now has in those movements that are not under the control of the will and that, therefore, do not proceed from the mind [but merely from the disposition of its organs]. I can readily acknowledge, for example, that in the case of a body sick with dropsy, it would be quite natural for it to suffer from a parched throat, which usually conveys a sensation of thirst to the mind, and for its nerves and other parts also to move in such a way that it takes a drink and thus aggravates the illness. And when nothing like this is harming the body, it is equally natural for it to be stimulated by a similar dryness in the throat and to take a drink to benefit itself. Now, when I consider the intended purpose of the clock, I could say that, since it does not indicate the time correctly, it is deviating from its own nature, and, in the same way, when I think of the machine of the human body as something formed for the motions which usually take place in it, I might believe that it, too, is deviating from its own nature, if its throat is dry when a drink does not benefit its own preservation. However, I am fully aware that this second meaning of the word nature is very different from the first. For it is merely a term that depends on my own thought, a designation with which I compare a sick person and a badly constructed clock with the idea of a healthy person and a properly constructed clock, and thus, the term is extrinsic to these objects. But by that [other use of the term nature] I understand something that is really found in things and that therefore contains a certain measure of the truth.(33)

Now, when I consider a body suffering from dropsy, even though I say that its nature has been corrupted, because it has a dry throat and yet does not need to drink, clearly the word nature is merely an extraneous term. However, when I consider the composite, that is, the mind united with such a body, I am not dealing with what is simply a term but with a true error of nature, because this composite is thirsty when drinking will do it harm. And thus I still have to enquire here why the goodness of God does not prevent its nature, taken in this sense, from being deceitful.

At this point, then, my initial observation is that there is a great difference between the mind and the body, given that the body is, by its very nature, always divisible, whereas the mind is completely indivisible. For, in fact, when I think of [my mind], that is, when I think of myself, to the extent that I am only a thinking thing, I cannot distinguish any parts within me. Instead, I understand that I am something completely individual and unified. And although my entire mind seems to be united with my entire body, nonetheless, I know that if a foot or arm or any other part of the body is sliced off, that loss will not take anything from my mind. And I cannot call the faculties of willing, feeling, understanding, and so on parts of the mind because it is the same single mind that wishes, feels, and understands. By contrast, I cannot think of any corporeal or extended substance that my thought is not capable of dividing easily into parts. From this very fact, I understand that the substance is divisible. This point alone would be enough to teach me that the mind is completely different from the body, if I did not already know that well enough from other sources.

Furthermore, I notice that the mind is not immediately affected by all parts of the body, but only by the brain, or perhaps even by just one small part of it, namely, the one in which our common sense is said to exist. Whenever this part is arranged in the same particular way, it delivers the same perception to the mind, even though the other parts of the body may be arranged quite differently at the time. This point has been demonstrated in countless experiments, which I need not review here.(34)

In addition, I notice that the nature of my body is such that no part of it can be moved by any other part some distance away which cannot also be moved in the same manner by any other part lying between them, even though the more distant part does nothing. So, for example, in a rope ABCD [which is taut throughout], if I pull on part D at the end, then the movement of the first part, A, will be no different than it would be if I pulled at one of the intermediate points, B or C, while the last part, D, remained motionless. And for a similar reason, when I feel pain in my foot, physics teaches me that this sensation occurs thanks to nerves spread throughout the foot. These nerves stretch from there to the brain, like cords, and when they are pulled in my foot, they also pull the inner parts of the brain, where they originate, and stimulate in them a certain motion which nature has established to influence the mind with a sense of pain apparently present in the foot. However, since these nerves have to pass through the tibia, the thigh, the loins, the back, and the neck in order to reach the brain from the foot, it can happen that, even if that portion of the nerves which is in the foot is not affected, but only one of the intermediate portions, the motion created in the brain is exactly the same as the one created there by an injured foot. As a result, the mind will necessarily feel the identical pain. And we should assume that the same is true with any other sensation whatsoever.

Finally, I notice that, since each of those motions created in that part of the brain which immediately affects the mind introduces into it only one particular sensation, we can, given this fact, come up with no better explanation than that this sensation, out of all the ones which could be introduced, is the one which serves to protect human health as effectively and frequently as possible [when a person is completely healthy]. But experience testifies to the fact that all sensations nature has given us are like this, and thus we can discover nothing at all in them which does not bear witness to the power and benevolence of God. Thus, for example, when the nerves in the foot are moved violently and more than usual, their motion, passing through the medulla of the spinal cord to the inner core of the brain, gives a signal there to the mind which makes it feel something—that is, it feels as if there is a pain in the foot. And that stimulates [the mind] to do everything it can to remove the cause of the pain as something injurious to the foot. Of course, God could have constituted the nature of human beings in such a way that this same motion in the brain communicated something else to the mind, for example, a sense of its own movements, either in the brain, or in the foot, or in any of the places in between—in short, of anything you wish. But nothing else would have served so well for the preservation of the body. In the same way, when we need a drink, a certain dryness arises in the throat which moves its nerves and, with their assistance, the inner parts of the brain. And this motion incites in the mind a sensation of thirst, because in this whole situation nothing is more useful for us to know than that we need a drink to preserve our health. The same is true for the other sensations.

From this it is clearly evident that, notwithstanding the immense goodness of God, human nature, given that it is composed of mind and body, cannot be anything other than something that occasionally deceives us. For if some cause, not in the foot, but in some other part through which the nerves stretch between the foot and the brain, or even in the brain itself, stimulates exactly the same motion as that which is normally aroused when a foot is injured, then pain will be felt as if it were in the foot, and the sensation will naturally be deceiving. Since that same motion in the brain is never capable of transmitting to the mind anything other than the identical sensation and since [the sensation] is habitually aroused much more frequently from an injury in the foot than from anything else in another place, it is quite reasonable that it should always transmit to the mind a pain in the foot rather than a pain in any other part of the body. And if sometimes dryness in the throat does not arise, as it usually does, from the fact that a drink is necessary for the health of the body, but from some different cause, as occurs in a patient suffering from dropsy, it is much better that it should deceive us in a case like that than if it were, by contrast, always deceiving us when the body is quite healthy. The same holds true with the other sensations.

This reflection is the greatest help, for it enables me not only to detect all the errors to which my nature is prone, but also to correct or to avoid them easily. For since I know that, in matters concerning what is beneficial to the body, all my senses show [me] what is true much more frequently than they deceive me, and since I can almost always use several of them to examine the same matter and, in addition, [can use] my memory, which connects present events with earlier ones, as well as my understanding, which has now ascertained all the causes of my errors, I should no longer fear that those things which present themselves to me every day through my senses are false. And I ought to dismiss all those exaggerated doubts of the past few days as ridiculous, particularly that most important [doubt] about sleep, which I did not distinguish from being awake. For now I notice a significant distinction between the two of them, given that our memory never links our dreams to all the other actions of our lives, as it [usually] does with those things which take place when we are awake. For clearly, if someone suddenly appears to me when I am awake and then immediately afterwards disappears, as happens in my dreams, so that I have no idea where he came from or where he went, I would, not unreasonably, judge that I had seen some apparition or phantom created in my brain [similar to the ones created when I am asleep], rather than a real person. But when certain things occur and I notice distinctly the place from which they came, where they are, and when they appeared to me, and when I can, without any interruption, link my perception of them to the rest of my life as a totality, then I am completely certain that this is taking place while I am awake and not in my sleep. And I should not have the slightest doubt about the truth of these perceptions if, after I have called upon all my senses, my memory, and my understanding to examine them, I find nothing in any of them which contradicts any of the others. For since God is not a deceiver, it must follow that in such cases I am not deceived. But because, in dealing with what we need to do, we cannot always take the time for such a scrupulous examination, we must concede that human life is often prone to error concerning particular things and that we need to acknowledge the frailty of our nature.


(1) Descartes was clearly dissatisfied with this subtitle, for in the second Latin edition, published a year after the first, the subtitle was changed to “In which the existence of God and the difference between the human soul and body are demonstrated,” a title which more accurately reflects the content of his argument. The original title page also includes (at the bottom) the phrase “With the Official Sanction and Approval of the Scholars” (Cum Privilegio, et Approbatione Doctorum), an odd addition, since the Meditations opens with a plea to the Sorbonne to grant him such a favour. Evidently, the learned doctors of the Sorbonne never gave the work their official approval. The title page of the first French edition follows the second Latin edition and adds “And the objections made against these Meditations by various very scholarly people, with the author’s responses.” The Latin and French editions spell the author’s name Des Cartes or Des-Cartes. [Back to Text]

(2) This heading does not appear in Descartes’ text. [Back to Text]

(3) The Fifth Council of the Lateran, an ecumenical gathering of Catholic Church officials, lasted from 1512 to 1517. Leo X (1475-1521) was elected pope after the Council had already been convened, and he continued it. [Back to Text]

(4) Archimedes (c. 287 BC to c. 212 BC) was a Greek mathematician and astronomer, famous for his mechanical inventions. Apollonius (c. 262 BC to c. 190 BC) was a Greek mathematician and astronomer who wrote on conic sections. Pappus (c.290 AD to c. 350 AD) was a famous Greek mathematician who wrote extensively on mathematical subjects. [Back to Text]

(5) The first Latin edition of the Meditations contained six sets of Objections and Replies, and over the years other sets appeared. None of these is included in this volume. At this point in the first edition, there is an Index listing the contents of the book. The index was dropped in the second edition. At the end of the Index there is a short list of emendations to the printed text. [Back to Text]

(6) The Concurrence of God is a Catholic term which refers to the cooperation of God in the actions of all natural beings. This cooperation is an essential part of such actions (for without God’s concurrence the living creature cannot exist), but it is not the only factor, since living creatures do have freedom to choose how to act. [Back to Text]

(7) Accidental properties or accidents (accidentia) are characteristics that are not essential to the definition or understanding of what something essentially is. They can be removed from the substance without destroying its identity. [Back to Text]

(8) In the French edition (1647), Descartes makes an interesting addition here, in which he indicates that for him the words soul (anima) and mind (mens) refer to the same thing—“l’esprit, ou l’âme de l’homme (ce que je ne distingue point) . . .” (“the human mind, or the human soul, for I make no distinction between them”). In this translation, unlike some others, mens is always translated as mind and anima as soul. The word animus, I have translated as mind or spirit. [Back to Text]

(9) This issue of the relationship of an idea in my mind to the reality of the source of that idea, a key part of Descartes’ argument, is dealt with in detail in the Third Meditation. [Back to Text]

(10) Natural light, a concept Descartes uses throughout the Meditations, refers to a natural inner awareness which reveals the truth or falsity of a thought, without involving anything external. The best example of something our natural light tells us is true is a mathematical axiom, like the statement, “Things equal to the same thing are equal to each other.” A colloquial definition might propose that our natural light reveals a truth that is rationally self-evident. [Back to Text]

(11) Physics, astronomy, and medicine all deal with composite objects, that is, with objects made up of parts, and we cannot be sure such objects are real, for they may be fantastic imaginary creations, like sirens and satyrs, put together from smaller real objects. However, mathematical concepts, like a square or an equation, do not raise such doubts, and mathematicians are not concerned about whether or not such concepts are a part of nature. [Back to Text]

(12) This image of the balance means that he will balance his old prejudices (opinions which he has held for a long time and will not abandon because they are probably true) and his new prejudices (his recently adopted view that these earlier ideas are all false or at least subject to doubt). Descartes claims that he will not get into error or danger by doing this, because he is engaging in a thought experiment in search of knowledge rather than acting upon an opinion which may contradict orthodox belief. Descartes was all too aware of what had happened to Galileo, who in 1633 had been put on trial, found guilty, and punished by the Church for his written opinions about astronomy. [Back to Text]

(13) A chimera is a fabulous monster with the head of a lion, the body of a goat, and the tail of a serpent. The word is often used to mean something illusory. [Back to Text]

(14) Descartes is famously associated with quotation cogitoergo sum (I think, therefore I am). While that sentence is a summary of his argument here, he never uses that particular wording in the Meditations. As he points out, the famous Latin quotation should be translated: I am thinking; therefore, I am, since I have no guarantee of existence when I am not thinking. [Back to Text]

(15) This well known example is meant to illustrate that we can have no certain knowledge of a physical object with our senses, because these merely give us sensations of an object’s attributes, which can change. And the imagination cannot provide us certain knowledge of the object because it cannot picture all the different changes an object might undergo. Thus, certain knowledge can come only from the understanding. [Back to Text]

(16) The term common sense refers to a faculty which, in traditional views of the mind, coordinated impressions from the various sense organs and communicated them to the mind. [Back to Text]

(17) This paragraph clarifies somewhat Descartes’ idea of perceiving something “clearly and distinctly” (a much discussed and crucial element in his argument). It seems to mean perceiving something with the certainty one experiences when dealing with mathematical truths. The only possible doubt one can have about such perceptions is that God might be deceiving him. [Back to Text]

(18) The sirens were two legendary sisters whose magical singing lured sailors to their deaths. A hippogriff is a fabulous creature of myth. [Back to Text]

(19) As mentioned in an earlier note, an accident is a property of a substance which is not a necessary part of the essence of that substance (like the colour of something, for example). An accident can be removed or changed, and the essential nature of the substance will remain the same. The phrase objective reality refers, not to objects, but to ideas. All ideas have objective reality, but, according to Descartes, an idea of a substance has more objective reality than an idea of some accidental property of that substance (e.g., the idea of a rock has more objective reality than the idea of the colour or texture of the rock). The idea of God has more objective reality than the idea of physical things, because God has a higher degree of reality (objects are finite, whereas God is infinite). The amount of objective reality in an idea thus depends upon the degree of reality in what the idea represents. This notion of different degrees of reality in ideas can perhaps be illustrated (somewhat) by the different degrees of reality we might ascribe to an old house, a picture of that house, and a dream about the picture of the house. These ideas all exist (i.e. are real) but, if we consider their content, some (we might say) contain more reality than others. Note that at this stage of the argument, Descartes has not yet established that God or objects outside himself exist. He has ideas of these things in him, but no certainty about whether these ideas represent anything real in the world outside himself. [Back to Text]

(20) An idea in my mind has objective reality (it exists). Therefore, the cause of that idea must contain an equal or higher degree of reality. If that were not the case, then the idea would contradict the principle that nothing can come of nothing. Formal reality, which objects in the world possess (if they exist), is a higher degree of reality than the objective reality of ideas. And eminent reality, the highest level of all, is a characteristic of God (if He exists) and other higher beings (if there are any). Perhaps this analogy (suggested by Andrew Latus) may help somewhat: if you are listening to music on a CD, the sounds you perceive have objective reality (they are in your mind); the CD has formal reality (as an object); the musical composition in the mind of the composer has a higher level (i.e., eminent) reality.  [Back to Text]

(21) Any idea I have is real (i.e., it exists) simply because I think it. My thinking confers formal reality on the idea. But the fact that I think of one thing rather than another (i.e., that my idea has a certain content) requires a source which has at least as much reality as or more reality than the content of the idea inside me. The objective reality of the idea must therefore have some formal cause (the subject of the next paragraph), and no idea can contain anything which was not present in its cause. [Back to Text]

(22) The key notion here is that an idea of something much greater than myself cannot come from me but must come from something outside my mind (and therefore that “something” must exist, and I am not alone in the world). Descartes in the following paragraphs is exploring whether any of his ideas of things falls into the category of ideas that must have come from outside him. He is attempting to deal with the problem of whether there is anything real outside of his own mind, because so far the only certainty he has is that he exists. [Back to Text]

(23) Eminent reality derives from the very principles of my being and is thus a higher level than the objective reality of ideas or the formal reality of objects. The claim here seems to be that because these attributes of objects are merely accidents, or modes of being (rather than having the formal reality of objects), they could exist in me potentially, simply because I am a substance. And therefore they could have come from within me and thus cannot confirm the existence of anything outside me. Hence, all my ideas of objects outside my mind could be self-generated and cannot demonstrate with any certainty the existence of those objects in the world. [Back to Text]

(24) As Descartes has mentioned above in the “Preface to the Reader,” this proof of God’s existence raised some important objections: “from the fact that I have within me the idea of something more perfect than myself, it does not follow . . . that what is represented by this idea exists.” As he tells us, Descartes copes with this objection by offering (in his Replies) the analogy of the idea of a perfect machine. The persuasiveness of the analogy depends upon how one interprets it. As John Cottingham has observed, if one saw that a normal child had drawn a remarkably original and accurate design for a complex new machine, one could reasonably assume that the idea had come from somewhere else (not from within the mind of the child), but if the child’s drawing was simply a square box with the words “big new machine” inside it, one would make no such conclusion. Those interested in pursuing the argument here should look at the First Objection and the Reply. [Back to Text ]

(25) Final causes are explanations which involve the purpose of something, in answer to the question: Why (i.e., for what purpose) was this thing created? Hence, they involve moral issues. Final causes (sometimes called first causes) are thus different from efficient (or secondary) causes, which seek to answer the question: How (i.e., by what step-by-step process) was this thing created? Modern science begins with the effort (energetically promoted by Descartes, Galileo, and Bacon, among others) to shift attention away from final causes onto efficient causes. [Back to Text]

(26) At this point in the argument Descartes has not yet established that anything outside his mind exists (other than God). Hence, God may have created a world of things, since He has the power to do that. However, the existence of such things is still merely a possibility. [Back to Text]

(27) A myriagon is a polygon with 10,000 sides. [Back to Text]

(28) Imagining something seems different from thinking of something, for the former requires a special effort and I could exist without the imagination (i.e., my mind would stay the same). Therefore, the imagination must be in some body outside my mind. However, the mind would still have to be connected somehow to this body, so that it could examine the contents of the imagination, whenever it wished to do so. [Back to Text]

(29) Note that when Descartes uses the phrase “in me” or “in myself” he means “in my mind,” for up to this point his entire sense of himself is that he is nothing but a thinking thing. Hence, something in his body is not part of “me.” [Back to Text]

(30) Descartes here, as part of his consideration of whether or not bodies exist, is exploring where his sense perceptions might come from. Since he is merely a thinking thing, these perceptions must come from somewhere else (not from him, because his mind has no control over them and because such perceptions do not involve thinking). These perceptions (i.e., the ideas they produce in his mind) are objectively real. Hence, their source must be something with a higher degree of reality, either some formal reality (as in corporeal objects) or some eminent reality (as in God or some power more real than physical objects). But since God is not a deceiver, He cannot be the source of these ideas (which can be deceptive). And since God has provided Descartes no way of determining any “higher” source for the ideas, they must come from physical objects, and thus such objects must exist. Therefore he can trust what he perceives clearly and distinctly in them. [Back to Text]

(31) This famous metaphor of the sailor on the ship (in the French the pilot [pilote] on the ship) highlights the most serious logical problem in Descartes’ theory of the division of the mind and the body: How do the mind and body interact? If there is nothing physical about my mind and nothing non-physical about my body, then how do I explain the fact that the two of them interact all the time? This is still the most important and vexing problem in biology. Descartes tried (elsewhere) to resolve the problem by locating a place where they interacted. He chose the pineal gland, because he could see no other use for it. [Back to Text]

(32) This distinction is between nature as an all-inclusive term meaning everything created by God and the more restricted sense of nature as the interaction of the body and the mind. Descartes is not interested here in pure intellection (which is entirely mental) or in physical properties of things (which are entirely corporeal), but rather in the connections between physical objects, sense perceptions, and mental states in the “mixture” of mind and body. [Back to Text]

(33) The human body without the mind and the clock are purely mechanical objects, and therefore they are entirely ruled by the laws of physics. They cannot truly deviate from their own nature (they have no choice about how they act). Hence, Descartes’ use of the word nature in this sense is extraneous or irrelevant and is, as he points out, merely a label which enables him to make a comparison between the two. But when he talks about the composite (the combination of body and mind), there is an element of choice involved, and choosing to do something harmful is truly a mistake and therefore a deviation from its nature. [Back to Text]

(34) In a tradition that goes back to Aristotle, the common sense (sensus communis) was a faculty which coordinated the sensations gathered from the five senses and communicated them to the mind. It is thus an important way of addressing the key issue of how the physical body interacts with the non-physical mind. [Back to Text]