데카르트 (2021) 제일철학에 관한 성찰 (2) 제3성찰

르네 데카르트 (2021). 제일철학에 관한 성찰. 이현복 옮김. 문예출판사. 

René Descartes (1984). The Philosophical Writings of Descartes. translated by John Cottingham, Robert Stoothoff, Dugald Murdoch. Volume II. Cambridge: Cambridge University Press.

 

THIRD MEDITATION

The existence of God

 

I will now shut my eyes, stop my ears, and withdraw all my senses. I will eliminate from my thoughts all images of bodily things, or rather, since this is hardly possible, I will regard all such images as vacuous, false and worthless. I will converse with myself and scrutinize myself more deeply; and in this way I will attempt to achieve, little by little, a more intimate knowledge of myself. I am a thing that thinks: that is, a thing that doubts, affirms, denies, understands a few things, is ignorant of many things,' is willing, is unwilling, and also which imagines and has sensory perceptions; for as I have noted before, even though the objects of my sensory experience and imagination may have no existence outside me, nonetheless the modes of thinking which I refer to as cases of sensory perception and imagination, in so far as they are simply modes of thinking, do exist within me — of that I am certain.

 

In this brief list I have gone through everything I truly know, or at least everything I have so far discovered that I know. Now I will cast around more carefully to see whether there may be other things within me which I have not yet noticed. I am certain that I am a thinking thing. Do I not therefore also know what is required for my being certain about anything? In this first item of knowledge there is simply a clear and distinct perception of what I am asserting; this would not be enough to make me certain of the truth of the matter if it could ever turn out that something which I perceived with such clarity and distinctness was false. So I now seem to be able to lay it down as a general rule that whatever I perceive very clearly and distinctly is true.

 

Yet I previously accepted as wholly certain and evident many things which I afterwards realized were doubtful. What were these? The earth, sky, stars, and everything else that I apprehended with the senses. But what was it about them that I perceived clearly? Just that the ideas, or thoughts, of such things appeared before my mind. Yet even now I am not denying that these ideas occur within me. But there was something else which I used to assert, and which through habitual belief I thought I perceived clearly, although I did not in fact do so. This was that there were things outside me which were the sources of my ideas and which resembled them in all respects. Here was my mistake; or at any rate, if my judgement was true, it was not thanks to the strength of my perception.

 

But what about when I was considering something very simple and straightforward in arithmetic or geometry, for example that two and three added together make five, and so on? Did I not see at least these things clearly enough to affirm their truth? Indeed, the only reason for my later judgement that they were open to doubt was that it occurred to me that perhaps some God could have given me a nature such that I was deceived even in matters which seemed most evident. And whenever my preconceived belief in the supreme power of God comes to mind, I cannot but admit that it would be easy for him, if he so desired, to bring it about that I go wrong even in those matters which I think I see utterly clearly with my mind's eye. Yet when I turn to the things them selves which I think I perceive very clearly, I am so convinced by them that I spontaneously declare: let whoever can do so deceive me, he will never bring it about that I am nothing, so long as I continue to think I am something; or make it true at some future time that I have never existed, since it is now true that I exist; or bring it about that two and three added together are more or less than five, or anything of this kind in which I see a manifest contradiction. And since I have no cause to think that there is a deceiving God, and I do not yet even know for sure whether there is a God at all, any reason for doubt which depends simply on this supposition is a very slight and, so to speak, metaphysical one. But in order to remove even this slight reason for doubt, as soon as the opportunity arises I must examine whether there is a God, and, if there is, whether he can be a deceiver. For if I do not know this, it seems that I can never be quite certain about anything else.

 

First, however, considerations of order appear to dictate that I now classify my thoughts into definite kinds, and ask which of them can properly be said to be the bearers of truth and falsity. Some of my thoughts are as it were the images of things, and it is only in these cases that the term 'idea' is strictly appropriate — for example, when I think of a man, or a chimera, or the sky, or an angel, or God. Other thoughts have various additional forms: thus when I will, or am afraid, or affirm, or deny, there is always a particular thing which I take as the object of my thought, but my thought includes something more than the likeness of that thing. Some thoughts in this category are called volitions or emotions, while others are called judgements.

 

Now as far as ideas are concerned, provided they are considered solely in themselves and I do not refer them to anything else, they cannot strictly speaking be false; for whether it is a goat or a chimera that I am imagining, it is just as true that I imagine the former as the latter. As for the will and the emotions, here too one need not worry about falsity; for even if the things which I may desire are wicked or even non-existent, that does not make it any less true that I desire them. Thus the only remaining thoughts where I must be on my guard against making a mistake are judgements. And the chief and most common mistake which is to be found here consists in my judging that the ideas which are in me resemble, or conform to, things located outside me. Of course, if I considered just the ideas themselves simply as modes of my thought, without referring them to anything else, they could scarcely give me any material for error.

 

Among my ideas, some appear to be innate, some to be adventitious,  and others to have been invented by me. My understanding of what a thing is, what truth is, and what thought is, seems to derive simply from my own nature. But my hearing a noise, as I do now, or seeing the sun, or feeling the fire, comes from things which are located outside me, or so I have hitherto judged. Lastly, sirens, hippogriffs and the like are my own invention. But perhaps all my ideas may be thought of as adventitious, or they may all be innate, or all made up; for as yet I have not clearly perceived their true origin.

 

But the chief question at this point concerns the ideas which I take to be derived from things existing outside me: what is my reason for thinking that they resemble these things? Nature has apparently taught me to think this. But in addition I know by experience that these ideas do not depend on my will, and hence that they do not depend simply on me. Frequently I notice them even when I do not want to: now, for example, I feel the heat whether I want to or not, and this is why I think that this sensation or idea of heat comes to me from something other than myself, namely the heat of the fire by which I am sitting. And the most obvious judgement for me to make is that the thing in question transmits to me its own likeness rather than something else.

 

I will now see if these arguments are strong enough. When I say 'Nature taught me to think this', all I mean is that a spontaneous impulse leads me to believe it, not that its truth has been revealed to me by some natural light. There is a big difference here. Whatever is revealed to me by the natural light — for example that from the fact that I am doubting it follows that I exist, and so on — cannot in any way be open to doubt. This is because there cannot be another faculty' both as trustworthy as the natural light and also capable of showing me that such things are not true. But as for my natural impulses, I have often judged in the past that they were pushing me in the wrong direction when it was a question of choosing the good, and I do not see why I should place any greater confidence in them in other matters.

 

Then again, although these ideas do not depend on my will, it does not follow that they must come from things located outside me. Just as the impulses which I was speaking of a moment ago seem opposed to my will even though they are within me, so there may be some other faculty not yet fully known to me, which produces these ideas without any assistance from external things; this is, after all, just how I have always thought ideas are produced in me when I am dreaming.

 

And finally, even if these ideas did come from things other than myself, it would not follow that they must resemble those things. Indeed, I think I have often discovered a great disparity in many cases. For example, there are two different ideas of the sun which I find within me. One of them, which is acquired as it were from the senses and which is a prime example of an idea which I reckon to come from an external source, makes the sun appear very small. The other idea is based on astronomical reasoning, that is, it is derived from certain notions which are innate in me (or else it is constructed by me in some other way), and this idea shows the sun to be several times larger than the earth. Obviously both these ideas cannot resemble the sun which exists outside me; and reason persuades me that the idea which seems to have emanated most directly from the sun itself has in fact no resemblance to it at all.

 

All these considerations are enough to establish that it is not reliable judgement but merely some blind impulse that has made me believe up till now that there exist things distinct from myself which transmit to me ideas or images of themselves through the sense organs or in some other way.

 

But it now occurs to me that there is another way of investigating whether some of the things of which I possess ideas exist outside me. In so far as the ideas are simply modes of thought, there is no recognizable inequality among them: they all appear to come from within me in the same fashion. But in so far as different ideas represent different things, it is clear that they differ widely. Undoubtedly, the ideas which represent substances to me amount to something more and, so to speak, contain within themselves more objective' reality than the ideas which merely represent modes or accidents. Again, the idea that gives me my understanding of a supreme God, eternal, infinite, omniscient, omnipotent and the creator of all things that exist apart from him, certainly has in it more objective reality than the ideas that represent finite substances.

 

Now it is manifest by the natural light that there must be at least as much in the efficient and total cause as in the effect of that cause. For where, I ask, could the effect get its reality from, if not from the cause? And how could the cause give it to the effect unless it possessed it? It follows from this both that something cannot arise from nothing, and also that what is more perfect — that is, contains in itself more reality — cannot arise from what is less perfect. And this is transparently true not only in the case of effects which possess actual or formal reality, but also in the case of ideas, where one is considering only objective reality. A stone, for example, which previously did not exist, cannot begin to exist unless it is produced by something which contains, either formally or eminently everything to be found in the stone; 2 similarly, heat cannot be produced in an object which was not previously hot, except by something of at least the same order of perfection as heat, and so on. But it is also true that the idea of heat, or of a stone, cannot exist in me unless it is put there by some cause which contains at least as much reality as I conceive to be in the heat or in the stone. For although this cause does not transfer any of its actual or formal reality to my idea, it should not on that account be supposed that it must be less real.' The nature of an idea is such that of itself it requires no formal reality except what it derives from my thought, of which it is a mode.4 But in order for a given idea to contain such and such objective reality, it must surely derive it from some cause which contains at least as much formal reality as there is objective reality in the idea. For if we suppose that an idea contains something which was not in its cause, it must have got this from nothing; yet the mode of being by which a thing exists objectively in the intellect by way of an idea, imperfect though it may be, is certainly not nothing, and so it cannot come from nothing.

 

And although the reality which I am considering in my ideas is merely objective reality, I must not on that account suppose that the same reality need not exist formally in the causes of my ideas, but that it is enough for it to be present in them objectively. For just as the objective mode of being belongs to ideas by their very nature, so the formal mode of being belongs to the causes of ideas — or at least the first and most important ones — by their very nature. And although one idea may perhaps originate from another, there cannot be an infinite regress here; eventually one must reach a primary idea, the cause of which will be like an archetype which contains formally all the reality which is present only objectively in the idea. So it is clear to me, by the natural light, that the ideas in me are like images which can easily fall short of the perfection of the things from which they are taken, but which cannot contain anything greater or more perfect.

 

The longer and more carefully I examine all these points, the more clearly and distinctly I recognize their truth. But what is my conclusion to be? If the objective reality of any of my ideas turns out to be so great that I am sure the same reality does not reside in me, either formally or eminently, and hence that I myself cannot be its cause, it will necessarily follow that I am not alone in the world, but that some other thing which is the cause of this idea also exists. But if no such idea is to be found in me, I shall have no argument to convince me of the existence of anything apart from myself. For despite a most careful and comprehensive survey, this is the only argument I have so far been able to find.

 

Among my ideas, apart from the idea which gives me a representation of myself, which cannot present any difficulty in this context, there are ideas which variously represent God, corporeal and inanimate things, angels, animals and finally other men like myself.

 

As far as concerns the ideas which represent other men, or animals, or angels, I have no difficulty in understanding that they could be put together from the ideas I have of myself, of corporeal things and of God, even if the world contained no men besides me, no animals and no angels.

 

As to my ideas of corporeal things, I can see nothing in them which is so great as to make it seem impossible that it originated in myself. For if I scrutinize them thoroughly and examine them one by one, in the way in which I examined the idea of the wax yesterday, I notice that the things which I perceive clearly and distinctly in them are very few in number. The list comprises size, or extension in length, breadth and depth; shape, which is a function of the boundaries of this extension; position, which is a relation between various items possessing shape; and motion, or change in position; to these may be added substance, duration and number. But as for all the rest, including light and colours, sounds, smells, tastes, heat and cold and the other tactile qualities, I think of these only in a very confused and obscure way, to the extent that I do not even know whether they are true or false, that is, whether the ideas I have of them are ideas of real things or of non-things.' For although, as I have noted before, falsity in the strict sense, or formal falsity, can occur only in judgements, there is another kind of falsity, material falsity, which occurs in ideas, when they represent non-things as things. For example, the ideas which I have of heat and cold contain so little clarity and distinctness that they do not enable me to tell whether cold is merely the absence of heat or vice versa, or whether both of them are real qualities, or neither is. And since there can be no ideas which are not as it were of things, if it is true that cold is nothing but the absence of heat, the idea which represents it to me as something real and positive deserves to be called false; and the same goes for other ideas of this kind.

 

Such ideas obviously do not require me to posit a source distinct from myself. For on the one hand, if they are false, that is, represent non-things, I know by the natural light that they arise from nothing — that is, they are in me only because of a deficiency and lack of perfection in my nature. If on the other hand they are true, then since the reality which they represent is so extremely slight that I cannot even distinguish it from a non-thing, I do not see why they cannot originate from myself.

 

With regard to the clear and distinct elements in my ideas of corporeal things, it appears that I could have borrowed some of these from my idea of myself, namely substance, duration, number and anything else of this kind. For example, I think that a stone is a substance, or is a thing capable of existing independently, and I also think that I am a substance. Admittedly I conceive of myself as a thing that thinks and is not extended, whereas I conceive of the stone as a thing that is extended and does not think, so that the two conceptions differ enormously; but they seem to agree with respect to the classification `substance'.' Again, I perceive that I now exist, and remember that I have existed for some time; moreover, I have various thoughts which I can count; it is in these ways that I acquire the ideas of duration and number which I can then transfer to other things. As for all the other elements which make up the ideas of corporeal things, namely extension, shape, position and move ment, these are not formally contained in me, since I am nothing but a thinking thing; but since they are merely modes of a substance,' and I am a substance, it seems possible that they are contained in me eminently.

 

So there remains only the idea of God; and I must consider whether there is anything in the idea which could not have originated in myself. By the word 'God' I understand a substance that is infinite, independent, supremely intelligent, supremely powerful, and which created both myself and everything else (if anything else there be) that exists. All these attributes are such that, the more carefully I concentrate on them, the less possible it seems that they' could have originated from me alone. So from what has been said it must be concluded that God necessarily exists.

 

It is true that I have the idea of substance in me in virtue of the fact that I am a substance; but this would not account for my having the idea of an infinite substance, when I am finite, unless this idea proceeded from some substance which really was infinite.

 

And I must not think that, just as my conceptions of rest and darkness are arrived at by negating movement and light, so my perception of the infinite is arrived at not by means of a true idea but merely by negating the finite. On the contrary, I clearly understand that there is more reality in an infinite substance than in a finite one, and hence that my perception of the infinite, that is God, is in some way prior to my perception of the finite, that is myself. For how could I understand that I doubted or desired — that is, lacked something — and that I was not wholly perfect, unless there were in me some idea of a more perfect being which enabled me to recognize my own defects by comparison?

 

Nor can it be said that this idea of God is perhaps materially false and so could have come from nothing, 3 which is what I observed just a moment ago in the case of the ideas of heat and cold, and so on. On the contrary, it is utterly clear and distinct, and contains in itself more objective reality than any other idea; hence there is no idea which is in itself truer or less liable to be suspected of falsehood. This idea of a supremely perfect and infinite being is, I say, true in the highest degree; for although perhaps one may imagine that such a being does not exist, it cannot be supposed that the idea of such a being represents something unreal, as I said with regard to the idea of cold. The idea is, moreover, utterly clear and distinct; for whatever I clearly and distinctly perceive as being real and true, and implying any perfection, is wholly contained in it. It does not matter that I do not grasp the infinite, or that there are countless additional attributes of God which I cannot in any way grasp, and perhaps cannot even reach in my thought; for it is in the nature of the infinite not to be grasped by a finite being like myself. It is enough that I understand' the infinite, and that I judge that all the attributes which I clearly perceive and know to imply some perfection — and perhaps countless others of which I am ignorant — are present in God either formally or eminently. This is enough to make the idea that I have of God the truest and most clear and distinct of all my ideas.

 

But perhaps I am something greater than I myself understand, and all the perfections which I attribute to God are somehow in me potentially, though not yet emerging or actualized. For I am now experiencing a gradual increase in my knowledge, and I see nothing to prevent its increasing more and more to infinity. Further, I see no reason why I should not be able to use this increased knowledge to acquire all the other perfections of God. And finally, if the potentiality for these perfections is already within me, why should not this be enough to generate the idea of such perfections?

 

But all this is impossible. First, though it is true that there is a gradual increase in my knowledge, and that I have many potentialities which are not yet actual, this is all quite irrelevant to the idea of God, which contains absolutely nothing that is potential; 2 indeed, this gradual increase in knowledge is itself the surest sign of imperfection. What is more, even if my knowledge always increases more and more, I recognize that it will never actually be infinite, since it will never reach the point where it is not capable of a further increase; God, on the other hand, I take to be actually infinite, so that nothing can be added to his perfection. And finally, I perceive that the objective being of an idea cannot be produced merely by potential being, which strictly speaking is nothing, but only by actual or formal being.

 

If one concentrates carefully, all this is quite evident by the natural light. But when I relax my concentration, and my mental vision is blinded by the images of things perceived by the senses, it is not so easy for me to remember why the idea of a being more perfect than myself must necessarily proceed from some being which is in reality more perfect. I should therefore like to go further and inquire whether I myself, who have this idea, could exist if no such being existed.

 

From whom, in that case, would I derive my existence? From myself presumably, or from my parents, or from some other beings less perfect than God; for nothing more perfect than God, or even as perfect, can be thought of or imagined.

 

Yet if I derived my existence from myself,' then I should neither doubt nor want, nor lack anything at all; for I should have given myself all the perfections of which I have any idea, and thus I should myself be God. I must not suppose that the items I lack would be more difficult to acquire than those I now have. On the contrary, it is clear that, since I am a thinking thing or substance, it would have been far more difficult for me to emerge out of nothing than merely to acquire knowledge of the many things of which I am ignorant — such knowledge being merely an accident of that substance. And if I had derived my existence from myself, which is a greater achievement, I should certainly not have denied myself the knowledge in question, which is something much easier to acquire, or indeed any of the attributes which I perceive to be contained in the idea of God; for none of them seem any harder to achieve. And if any of them were harder to achieve, they would certainly appear so to me, if I had indeed got all my other attributes from myself, since I should experience a limitation of my power in this respect.

 

I do not escape the force of these arguments by supposing that I have always existed as I do now, as if it followed from this that there was no need to look for any author of my existence. For a lifespan can be divided into countless parts, each completely independent of the others, so that it does not follow from the fact that I existed a little while ago that I must st now, unless there is some cause which as it were creates me afresh at this moment — that is, which preserves me. For it is quite clear to anyone who attentively considers the nature of time that the same power and action are needed to preserve anything at each individual moment of its duration as would be required to create that thing anew if it were not yet in existence. Hence the distinction between preservation and creation is only a conceptual one,' and this is one of the things that are evident by the natural light.

 

I must therefore now ask myself whether I possess some power enabling me to bring it about that I who now exist will still exist a little while from now. For since I am nothing but a thinking thing — or at least since I am now concerned only and precisely with that part of me which is a thinking thing — if there were such a power in me, I should undoubtedly be aware of it. But I experience no such power, and this very fact makes me recognize most clearly that I depend on some being distinct from myself.

 

But perhaps this being is not God, and perhaps I was produced either by my parents or by other causes less perfect than God. No; for as I have said before, it is quite clear that there must be at least as much in the cause as in the effect.' And therefore whatever kind of cause is eventually proposed, since I am a thinking thing and have within me some idea of God, it must be admitted that what caused me is itself a thinking thing and possesses the idea of all the perfections which I attribute to God. In respect of this cause one may again inquire whether it derives its existence from itself or from another cause. If from itself, then it is clear 5o from what has been said that it is itself God, since if it has the power of existing through its own might,2 then undoubtedly it also has the power of actually possessing all the perfections of which it has an idea — that is, all the perfections which I conceive to be in God. If, on the other hand, it derives its existence from another cause, then the same question may be repeated concerning this further cause, namely whether it derives its existence from itself or from another cause, until eventually the ultimate cause is reached, and this will be God.

 

It is clear enough that an infinite regress is impossible here, especially since I am dealing not just with the cause that produced me in the past, but also and most importantly with the cause that preserves me at the present moment.

 

Nor can it be supposed that several partial causes contributed to my creation, or that I received the idea of one of the perfections which I attribute to God from one cause and the idea of another from another — the supposition here being that all the perfections are to be found somewhere in the universe but not joined together in a single being, God. On the contrary, the unity, the simplicity, or the inseparability of all the attributes of God is one of the most important of the perfections which I understand him to have. And surely the idea of the unity of all his perfections could not have been placed in me by any cause which did not also provide me with the ideas of the other perfections; for no cause could have made me understand the interconnection and inseparability of the perfections without at the same time making me recognize what they were.

 

Lastly, as regards my parents, even if everything I have ever believed about them is true, it is certainly not they who preserve me; and in so far as I am a thinking thing, they did not even make me; they merely placed certain dispositions in the matter which I have always regarded as containing me, or rather my mind, for that is all I now take myself to be. So there can be no diffiulty regarding my parents in this context. Altogether then, it must be concluded that the mere fact that I exist and have within me an idea of a most perfect being, that is, God, provides a very clear proof that God indeed exists.

 

It only remains for me to examine how I received this idea from God. For I did not acquire it from the senses; it has never come to me unexpectedly, as usually happens with the ideas of things that are per ceivable by the senses, when these things present themselves to the external sense organs — or seem to do so. And it was not invented by me either; for I am plainly unable either to take away anything from it or to add anything to it. The only remaining alternative is that it is innate in me, just as the idea of myself is innate in me.

 

And indeed it is no surprise that God, in creating me, should have placed this idea in me to be, as it were, the mark of the craftsman stamped on his work — not that the mark need be anything distinct from the work itself. But the mere fact that God created me is a very strong basis for believing that I am somehow made in his image and likeness, and that I perceive that likeness, which includes the idea of God, by the same faculty which enables me to perceive myself. That is, when I turn my mind's eye upon myself, I understand that I am a thing which is incomplete and dependent on another and which aspires without limit to ever greater and better things; but I also understand at the same time that he on whom I depend has within him all those greater things, not just indefinitely and potentially but actually and infinitely, and hence that he is God. The whole force of the argument lies in this: I recognize that it would be impossible for me to exist with the kind of nature I have — that is, having within me the idea of God — were it not the case that God really existed. By 'God' I mean the very being the idea of whom is within me, that is, the possessor of all the perfections which I cannot grasp, but can somehow reach in my thought, who is subject to no defects whatsoever.' It is clear enough from this that he cannot be a deceiver, since it is manifest by the natural light that all fraud and deception depend on some defect.

 

But before examining this point more carefully and investigating other truths which may be derived from it, I should like to pause here and spend some time in the contemplation of God; to reflect on his attributes, and to gaze with wonder and adoration on the beauty of this immense light, so far as the eye of my darkened intellect can bear it. For just as we believe through faith that the supreme happiness of the next life consists solely in the contemplation of the divine majesty, so experience tells us that this same contemplation, albeit much less perfect, enables us to know the greatest joy of which we are capable in this life.