from
The Meditations Concerning First Philosophy
by
René Descartes

There is this further difference, that in geometry everyone is persuaded that nothing should be written for which there is no certain proof. Therefore, those who are not well versed in the field are much more apt to make the mistake of accepting false demonstrations in order to make others believe that they understand them than they are to make the mistake of rejecting good ones. It is different in philosophy, where it is believed that there is nothing about which it is not possible to argue on either side. Thus few people engage in the search for truth, and many, who wish to acquire a reputation as clever thinkers, bend all their efforts to arrogant opposition to the most obvious truths.

That is why, since my arguments belong to philosophy, however strong they may be, I do not suppose that they will have any great effect unless you take them under your protection.

The second objection is that it does not follow from the fact that I have in my mind the idea of a thing more perfect than I am that this idea is more perfect than myself, much less that what is represented by this idea exists.

But I reply that in this word “idea” there is here an equivocation. For it can be taken materially, as an operation of my intellect, and in this sense it cannot be said to be more perfect than myself; or it can be taken objectively for the body which is represented by this operation, which, even though it is not supposed to exist outside of my understanding, can nevertheless be more perfect than myself in respect to its essence. In the rest of this treatise I shall show more fully how it follows from the mere fact that I have in my mind an idea of something more perfect than myself that this thing really exists.

[...] I do not wish to reply to the arguments here, for fear of being obliged first to report them.

I shall only say, in general, that the arguments which atheists use to combat the existence of God always depend either upon the assumption that God has human characteristics, or else upon the assumption that our own minds have so much ability and wisdom that we presume to delimit and comprehend what God can and should do. Thus all that atheists allege will give us no difficulty if only we remind ourselves that we should consider our minds to be finite and limited, and God to be an infinite and incomprehensible Being.

And at last here I am, having insensibly returned to where I wished to be; for since it is at present manifest to me that even bodies are not properly known by the senses nor by the faculty of imagination, but by the understanding alone; and since they are not known in so far as they are seen or touched, but only in so far as they are understood by thinking, I see clearly that there is nothing easier for me to understand than my mind.

If these ideas are considered only in so far as they are particular modes of thought, I do not recognize any difference or inequality among them, and all of them appear to arise from myself in the same fashion. But considering them as images, of which some represent one thing and some another, it is evident that they differ greatly among themselves. For those that represent substances are undoubtedly something more, and contain in themselves, so to speak, more objective reality, or, rather, participate by representation in a higher degree of being or perfection, than those that represent only modes or accidents. Furthermore, that by which I conceive a supreme God, eternal, infinite, immutable, omniscient, omnipotent, and the universal creator of all things that exist outside of himself—that idea, I say, certainly contains in itself more objective reality than do those by which finite substances are represented.

Now it is obvious, according to the light of nature, that there must be at least as much reality in the total efficient cause as in its effect, for whence can the effect derive its reality, if not from its cause? And how could this cause communicate reality to the effect, unless it possessed it in itself?

And from this it follows, not only that something cannot be derived from nothing, but also that the more perfect—that is to say, that which contains in itself more reality—cannot be a consequence of and dependent on the less perfect.

And consequently we must necessarily conclude from all that I have previously said that God exists. For even though the idea of substance exists in me from the very fact that I am a substance, I would nevertheless have no idea of an infinite substance, I who am a finite being, unless the idea had been placed in me by some substance which was in fact infinite.

And I must not imagine that I do not conceive infinity as a real idea, but only through the negation of what is finite in the manner that I comprehend rest and darkness as the negation of movement and light. On the contrary, I see manifestly that there is more reality in infinite substance than in finite substance, and my notion of the infinite is somehow prior to that of the finite, that is, the notion of God is prior to that of myself. For how would it be possible for me to know that I doubt and that I desire—that is, that I lack something and am not all perfect—if I did not have in myself any idea of a being more perfect than my own, by comparison with which I might recognize the defects of my own nature?

This idea, I say, of a supremely perfect and infinite being, is entirely true; for even though one might imagine that such a being does not exist, nevertheless one cannot imagine that the idea of it does not represent anything real, as I have just said of the idea of cold. It is also very clear and very distinct, since everything real and true which my mind conceives clearly and distinctly, and which contains some perfection, is contained and wholly included in this idea. And this will be no less true even though I do not comprehend the infinite and though there is in God an infinity of things which I cannot comprehend, or even perhaps suggest in thought, for it is the nature of infinity that I, who am finite and limited, cannot comprehend it. It is enough that I understand this and that I judge that all qualities which I conceive clearly and in which I know that there is some perfection, and possibly also an infinity of other qualities of which I am ignorant, are in God formally or eminently.

Actually it is quite clear and evident to all who will consider attentively the nature of time that a substance, to be conserved at every moment that it endures, needs the same power and the same action which would be necessary to produce it and create it anew if it did not yet exist. Thus the light of nature makes us see clearly that conservation and creation differ only in regard to our manner of thinking and not in reality.

It is therefore only necessary here for me to question myself and consider my own nature to see whether I possess some power and ability by means of which I can bring it about that I, who exist now, shall still exist a moment later. For since I am nothing but a being which thinks, or at least since we are so far concerned only with that part of me, if such a power resided in me, certainly I should at least be conscious of it and recognize it. But I am aware of no such thing, and from that fact I recognize evidently that I am dependent upon some being different from myself.

And I see that I am, as it were, a mean between God and nothingness, that is, so placed between the supreme Being and not-being that, in so far as a supreme Being has produced me, there is truly nothing in me which could lead me into error; but if I consider myself as somehow participating in nothingness or not-being, that is, in so far as I am not myself the supreme being and am lacking many things, I should not be astonished if I go wrong.

Thus I clearly recognize that error as such is not something real which depends upon God, but only a deficiency.

For, knowing by now that my nature is extremely weak and limited and that God’s, on the contrary, is immense, incomprehensible, and infinite, I no longer have any difficulty in recognizing that there are an infinity of things within his power the causes of which lie beyond the powers of my mind. And this consideration alone is sufficient to persuade me that all causes of the type we are accustomed to call final are useless in physical affairs, for it does not seem possible for me, without presumption, to seek and undertake to discover the purposes of God.

Furthermore, it occurs to me that we should not consider a single creation separately when we investigate whether the works of God are perfect, but generally all created objects together. For the same thing which might perhaps, with some sort of justification, appear to be very imperfect if it were alone in the world is seen to be very perfect when considered as constituting a part of this whole universe.

From all this I recognize, on the one hand, that the cause of my errors is not the power of willing considered by itself, which I have received from God, for it is very ample and perfect in its own kind. Nor, on the other hand, is it the power of conceiving; for since I conceive nothing except by means of this power which God has given me in order to conceive, no doubt everything I conceive I conceive properly, and it is not possible for me to be deceived in that respect.

Whence, then, do my errors arise? Only from the fact that the will is more ample and far-reaching than the understanding, so that I do not restrain it within the same limits but extend it even to those things which I do not understand. Being indifferent about such matters, it very easily is turned aside from the true and the good. And thus it happens that I make mistakes and that I sin.

Thus it is no less self-contradictory to conceive of a God, a supremely perfect Being, who lacks existence—that is, who lacks some perfection—than it is to conceive of a mountain for which there is no valley.

But even though in fact I cannot conceive of a God without existence, any more than of a mountain without a valley, nevertheless, just as from the mere fact that I conceive a mountain with a valley, it does not follow that any mountain exists in the world, so likewise, though I conceive of God as existing, it does not seem to follow for this reason that God exists. [...]

It is here that there is sophistry hidden. For from the fact that I cannot conceive of a mountain without a valley it does not follow that there is a mountain or a valley anywhere, but only that the mountain and the valley, whether they exist or not, are inseparable from each other. From the fact alone that I cannot conceive God except as existing, it follows that existence is inseparable from him, and consequently that he does, in truth, exist.

For I can persuade myself that I was so made by nature that I could easily make mistakes, even in those matters which I believe I understand with the greatest evidence, especially because I remember having often judged many things true and certain, which, later, other reasons constrained me to consider absolutely false.

But after having recognized that there is a God, and having recognized at the same time that all things are dependent upon him and that he is not a deceiver, I can infer as a consequence that everything which I conceive clearly and distinctly is necessarily true.