I Think Therefore I Am

My first meditations are so metaphysical and so uncommon. They might not be acceptable to everyone.

The foundations that I have laid are secure.

Our opinions are highly uncertain. We should reject as absolutely false all opinions which could be doubted. This is so that we can have solid truths.

Our senses sometimes deceive us. That is why I supposed that there existed nothing really such as they presented to us.

This is because some men:

• err in reasoning, and
• fall into paralogisms, even on the simplest matters of geometry

I was as open to error as any other. So I rejected as false all the reasonings I had hitherto taken as fact.

The very same thoughts which we experience when awake may also be experienced when we are asleep. But when asleep, they are not true. But it means that all the objects (presentations) that had in my mind when awake were just as false as the illusions of my dreams.

I thus wished to think that all was false even myself who was thinking of it.

The Non-Physical Existence

I realized that I think, therefore I exist (cogito ergo sum). This was so certain that it could not be doubted.

I concluded that I might accept it as the first principle of my philosophy.

If I had no body, then I would not have any physical existence. But it does not mean that I could not have a [non-physical] existence.

On the contrary, it most clearly and certainly followed that I could exist [as I could think about it].

On the other hand, if I stopped thinking then I would no longer exist, even if all the other objects which I had imagined retained their existence in reality.

I thence concluded that:

• I was a substance whose whole essence or nature consists only in thinking
• this substance may exist without physical place, or any material thing
• this “I” is the mind by which I am what I am
  • It is wholly distinct from the body
  • It is even more easily known than the body
  • It would exist even if the body did not.

“I think, therefore I am” has nothing which assures of their truth beyond this.

As a general rule, all the things which we very clearly conceive are true.

However, there is some difficulty in rightly determining the objects which we clearly conceive.

My being was not wholly perfect. So I thought of something more perfect than myself.

I came up with the idea of God as perfection.

I knew some perfections which I lacked. It meant that I was not the only being in existence.

But, on the contrary, that there was logically some other more perfect Being upon whom I was dependent, and from whom I had received all that I possessed.

If I had existed alone, and independently of every other being, so as be perfect, then I would never be able to think of the words infinite, eternal, immutable, omniscient, all-powerful and all the other things that I was not. I therefore put all these perfections in God.

For in order to know the nature of God, I only had judge whether all the properties in my mind are perfect.

I was assured that no one which indicated any imperfection was in him, and that none of the rest was awanting.

Thus I perceived that doubt, inconstancy, sadness, etc, could not be found in God, since I myself would have been happy to be free from them.

Besides, I had ideas of many sensible and corporeal things. I might have been dreaming when I had them. They might be false. But they are still my thoughts.

But I had already very clearly recognized in myself that the intelligent nature is distinct from the corporeal.

All composition is an evidence of dependency. Thus, a state of dependency is manifestly a state of imperfection.

I therefore determined that it could not be a perfection in God to be compounded of these two natures and that consequently he was not so compounded.

If there were any bodies in the world, or even any intelligences, or other natures that were not wholly perfect, their existence depended on his power in such a way that they could not subsist without him for a single moment.

I represented to myself the shapes of the geometers. I conceived them to be a continuous body or a space:

• indefinitely extended in length, width, and height or depth
• divisible into parts which admit of different figures and sizes
• capable of being moved or transposed in all manner of ways.

These demonstrations lead to common consent, producing great certitude.

This consent is based on the fact that they are clearly conceived in accordance with the rules I have already laid down.

In the next place, I perceived that there was nothing at all in these demonstrations which could assure me of the existence of their object.

Thus, I distinctly think of a triangle has its 3 angles being equal to 2 right angles.

• But it does not mean that any triangle existed in reality.

On the contrary, if my basis is the existence of the idea of 3 angles to 2 right angles, then it follows that the idea of a triangle exists.

If points that are equidistant from the center exists, then it follows that a sphere exists.

I found existing things in my thoughts. If follows that a Perfect Being that has all these thoughts exists.

Consequently, God, this Perfect Being, exists just as the shapes of geometry exist.

People have trouble realizing this because they never raise their thoughts above sensible objects. They are so used to consider only the ideas from material objects, that all that is not materially imaginable seems to them not intelligible.

Philosophers of the schools accept as a maxim that all our understanding comes from the senses and that the ideas of God and of the soul have never been through our senses.

Thus, those who perceive God and the soul through the material senses are like people who use their eyes to hear sounds or smell odours.

Finally, people who still doubt the existence of God and the soul should learn all my other propositions.

God and the soul exist just as we have a body and just as the stars and the earth exist.

We have a strong moral assurance of these things.

Yet at the same time no-one, unless his intellect is impaired, can deny, when the question relates to a metaphysical certitude, that there is sufficient reason to exclude entire assurance, in the observation that when asleep we can in the same way imagine ourselves possessed of another body and that we see other stars and another earth, when there is nothing of the kind.

For how do we know that the thoughts which occur in dreaming are false rather than those other which we experience when awake, since the former are often not less vivid and distinct than the latter?

Genius men study this question as long as they want. But I do not believe that they will be able to give any reason which can remove this doubt, unless they presuppose the existence of God.

For, in the first place even the principle which I have already taken as a rule, viz., that all the things which we clearly and distinctly conceive are true, is certain only because God is or exists and because he is a Perfect Being, and because all that we possess is derived from him= whence it follows that our ideas or notions, which to the extent of their clearness and distinctness are real, and proceed from God, must to that extent be true.

Accordingly, whereas we not infrequently have ideas or notions in which some falsity is contained, this can only be the case with such as are to some extent confused and obscure, and in this proceed from nothing (participate of negation), that is, exist in us thus confused because we are not wholly perfect.

it is not less repugnant that falsity or imperfection, in so far as it is imperfection, should proceed from God, than that truth or perfection should proceed from nothing. But if we did not know that all which we possess of real and true proceeds from a Perfect and Infinite Being, however clear and distinct our ideas might be, we should have no ground on that account for the assurance that they possessed the perfection of being true.

But after the knowledge of God and of the soul has rendered us certain of this rule, we can easily understand that the truth of the thoughts we experience when awake, ought not in the slightest degree to be called in question on account of the illusions of our dreams.

For if it happened that an individual, even when asleep, had some very distinct idea, as, for example, if a geometer should discover some new demonstration, the circumstance of his being asleep would not militate against its truth; and as for the most ordinary error of our dreams, which consists in their representing to us various objects in the same way as our external senses, this is not prejudicial, since it leads us very properly to suspect the truth of the ideas of sense;

For we are not infrequently deceived in the same manner when awake; as when persons in the jaundice see all objects yellow, or when the stars or bodies at a great distance appear to us much smaller than they are. For, in fine, whether awake or asleep, we ought never to allow ourselves to be persuaded of the truth of anything unless on the evidence of our reason.

I say of our reason, and not of our imagination or of our senses= thus, for example, although we very clearly see the sun, we ought not therefore to determine that it is only of the size which our sense of sight presents.

We may distinctly imagine the head of a lion joined to the body of a goat, without being therefore shut up to the conclusion that a chimaera exists; for it is not a dictate of reason that what we thus see or imagine is in reality existent;

but it plainly tells us that all our ideas or notions contain in them some truth; for otherwise it could not be that God, who is wholly perfect and veracious, should have placed them in us.

Our reasonings are clearer and most complete when we are awake, and not asleep.

Sometimes, our imagination is more lively and distinct than our waking moments.

Reason further dictates that, since all our thoughts cannot be true because of our partial imperfection, those possessing truth must infallibly be found in the experience of our waking moments rather than in that of our dreams.