The Aim of Life - Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

Rene Descartes

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

Proofs of the Existence of God and of the Human Soul


Pursuit of truth is easily acknowledged to be an ideal for every thinking and living being. But what is truth and how can it be pursued? This has been debated through the centuries. What is claimed to be true by some is opposed by others. Some believe that truth is what our physical senses perceive; some others believe that truth is what our reasoning mind comes to conceive as real; some others believe that truth can be known neither by the senses nor by the reasoning intellect; according to them, truth is given to us through God's revelation.

Truth by revelation became a preponderant concept in the West during the Middle Ages. The great theologians of the Christian religion propounded the theory of revelation and pointed out that there was a clear distinction between reason and revelation. However, with the advent of the Renaissance, when the ancient Greek knowledge began to spread once again throughout Europe, a new age of reason began to dawn. Now, by means of physical verification certain facts were established which turned out to be in direct opposition to what was thought to be the revealed truth. The great scientists of this time revolutionised the concept of the universe and the place of earth and man within it. Mathematics, which had already reached great heights in ancient Greek civilisation, was now developed as a perfect model of science. That a proposition must be proved to be true before it can be accepted as true became widely acknowledged. Along with this came a serious questioning as to whether something should be accepted as true simply on the basis of faith, because

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

it was a revelation or an unquestioned dogma. It is in this psychological climate that there arose a brilliant star in the firmament of thought who crystallised the tendency of discovering the truth by means of pure reason. This was Rene Descartes.

Rene Descartes was born in 1596 in La Haye, a small town in the region of Touraine in France. His father was a councillor of the Parliament of Brittany and belonged to the gentry. He left his son enough means to live as a gentleman of leisure — a way of life which Descartes cherished. His mother died of ill-health a year after his birth. Her delicate disposition was inherited by him and he had to be carefully brought up by a nurse during his childhood.

At the age of ten, he entered the Jesuit College of La Fleche, where he received a better grounding in Mathematics than he could have got at other universities of the time: "The subject being specially dear to me for it alone could lead to certain knowledge. " He was a brilliant student and he received special attention from his teachers. He completed his education at the University of Poitiers, with some study of law and probably of medicine. He then went to Paris, where he found social life not quite to his taste and he began to seek quiet and leisure to carry on his work.

The decisive event of his life came about on November 10, 1619, during a night of great inspiration and "elan ". He had successive visions or dreams in which he saw flashes of light and heard thunder. It seemed to him that some divine spirit was revealing to him a new philosophy. At the core of this revelation was the intuition that there was a fundamental accord between the laws of nature and those of the science of mathematics.

To carry on this work he wished to be left undisturbed. He did not think it would be possible to be so in France for several reasons. He thus enlisted, as a voluntary gentleman, in the Dutch army and moved to Holland, where he lived for twenty years. Holland in the seventeenth century was a very free and hospitable place for those spirits of Europe who were breaking fresh ground and did not want any constraints of tradition imposed upon them. Later, Descartes also spent some time in the Bavarian army. These occupations gave him leisure, and also the seclusion from social life.

He carried on, however, an enlightened intellectual correspondence with Queen Christina of Sweden, a lady of great intelligence, who persuaded him to take up residence at her court so that she could take lessons from him. He then moved to Sweden, and that is where he died in 1650. Descartes' writings seem to have been done during short periods of great concentration. His most important works are Discourse on Method and Meditations.

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

That truth must be pursued as the very aim of intellectual life is the dominant message of Descartes. And what is particularly significant in Descartes is the method of doubt which he came to perfect. Indeed, Descartes did not preach the method of doubting in a spirit of making the act of doubting fashionable. This is important to underline because among many pseudo-intellectuals there is a fashion to pronounce every proposition made to them to be doubtful and then to remain quiescent, throwing the entire burden of the pursuit of truth on the propounder. What Descartes pointed out was that doubt itself should be based upon convincing grounds, and he was ready to doubt even those convincing grounds on the basis of some other convincing grounds which he was ready to doubt on other convincing grounds, and so on. His method of doubt was a responsible method, deeply conceived, and it was committed to the pursuit of truth right up to its possible end; at the same time, he did not assume that this process of doubting would ever end at all. It was only in respect of the statement "I am thinking" that he saw clearly that it was impossible to doubt it. In that case, the act of doubting revealed its own presupposition, namely the process of thinking. Thus this presupposition affirmed. Itself through the very act of doubting. Therefore he found that it was impossible to doubt the proposition "I am thinking" (cogito) And from the proposition "I am thinking" he saw that an inevitable proposition followed, namely, "I am" (sum). 'This is the famous Cartesian proposition "Cogito ergo sum". Indeed, in the later history of philosophy this argument, "I think therefore I am" has come to be questioned, and in the Cartesian spirit we may welcome this further questioning, for it opens up a new chapter in the pursuit of truth. But what is most valuable in Descartes is his incisive spirit of enquiry and his boldness to pursue the truth even at the risk of never reaching it. He insisted that reason is an inborn light within us, it is with this light that we must pursue the path to the discovery of truth.

What was Descartes' standard or criterion by which to judge whether an idea was true or false? His answer, which does not seem especially convincing at first sight is found to be quite profound as one thinks of it more and more deeply. According to him, an idea which is clear and precise is true. Negatively speaking, an idea which is unclear and imprecise is untrue. We shall leave it to the reader to doubt if this Cartesian definition is valid or not, on the condition that he finds valid grounds to doubt it.

Descartes is not only famous for his doubting, but also for his argument to prove the existence of God. Descartes came to accept the existence of God because he found that his argument established the existence of God beyond any possibility

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

of doubt. This argument can be stated in difficult, even quite sophisticated ways, but it can also be stated very simply, although some staunch spirits may not pardon this kind of formulation. But if we are permitted, we may formulate Descartes ' argument as follows: "I cannot doubt that I am thinking because to doubt that I am thinking, I must think. Among numerous thoughts, there is the thought of perfection. Perfection means that which lacks nothing. Existence is something, therefore perfection cannot lack existence. By perfection is meant God. That means that God cannot lack existence. Therefore God exists. "

According to Descartes' argument, the "idea" of God implies the actual existence of God. What it affirms is that the idea of God is so special that to think of God and not to think of him as existing is impossible. Following Descartes, one can go further and say that, truly speaking, to think is to think of God. There is only one thing that can be thought of, and that is God. God as absolute and perfect being is not only conceivable but it is the only thing that can be conceived of.

Whether this argument seems convincing or not is to be judged by the reader, and we shall not burden him with further reflections. In the meantime, let us study in the following text the interesting meditations of Descartes, which will show us some of the contours of the adventure of his thought.


Philosopher in Meditation, by Rembrandt

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

I do not know whether I ought to touch upon my first meditations here, for they are so metaphysical and out of the ordinary that they might not be interesting to most people. Nevertheless, in order to show whether my fundamental notions are sufficiently sound, I find myself more or less constrained to speak of them. I had noticed for a long time that in practice it is sometimes necessary to follow opinions which we know to be very uncertain, just as though they were indubitable, as I stated before; but inasmuch as I desired to devote myself wholly to the search for truth, I thought that I should take a course precisely contrary, and reject as absolutely false anything of which I could have the least doubt, in order to see whether anything would be left after this procedure which could be called wholly certain. Thus, as our senses deceive us at times, I was ready to suppose that nothing was at all the way our senses represented them to be. As there are men who make mistakes in reasoning even on the simplest topics in geometry, I judged that I was as liable to error as any other, and rejected as false all the reasoning which I had previously accepted as valid demonstration. Finally, as the same precepts which we have when awake may come to us when asleep without their being true, I decided to suppose that nothing that had ever entered my mind was more real than the illusions of my dreams. But I soon noticed that while I thus wished to think everything false, it was necessarily true that I who thought so was something. Since this truth, / think, therefore I am, was so firm and assured that all the most extravagant suppositions of the sceptics were unable to shake it, I judged that I could safely accept it as the first principle of the philosophy I was seeking.

I then examined closely what I was, and saw that I could imagine that I had no body, and that there was no world nor any place that I occupied, but that I could not imagine for a moment that I did not exist. On the contrary, from the very fact that I doubted the truth of other things, it followed very evidently and very certainly that I existed. On the other hand, if I had ceased to think while all the rest of what I had ever imagined remained true, I would have had no reason to believe that I existed; therefore I concluded that I was a substance whose whole essence or nature was only to think, and which, to exist, has no need of space nor of any material thing. Thus it follows that this ego, this soul, by which I am what I am, is entirely distinct from the body and is easier to know than the latter, and that even if the body were not, the soul would not cease to be all that it now is.

Next I considered in general what is required of a proposition for it to be true and certain, for since I had just discovered one to be such, I thought I ought also to

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

know of what that certitude consisted. I saw that there was nothing at all in this statement, "I think, therefore I am", to assure me that I was saying the truth, unless it was that I saw very clearly that to think one must exist. So I judged that I could accept as a general rule that the things which we conceive very clearly and very distinctly are always true, but that there may well be some difficulty in deciding which are those which we conceive distinctly.

After that I reflected upon the fact that I doubted, and that, in consequence, my spirit was not wholly perfect, for I saw clearly that it was a greater perfection to know than to doubt. I decided to ascertain from what source I have learned to think of something more perfect than myself, and it appeared evident that it must have been from some nature which was in fact more perfect. As for my ideas about many other things outside of me, as the sky, earth, light, heat, and thousands of other things, I was not so much troubled to discover where they came from, because I found nothing in them superior to my own nature. If they really existed, I could believe that whatever perfection they possessed might be derived from my own nature; if they did not exist, I could believe that they were derived from nothingness, that is, that they were derived from my own defects. But this could not be the explanation of my idea of a being more perfect than my own. To derive it from nothingness was manifestly impossible, and it is no less repugnant to good sense to assume that what is more perfect comes from and depends on the less perfect than it is to assume that something comes from nothing, so that I could not assume that it came from myself. Thus the only hypothesis left was that this idea was put in my mind by a nature that was really more perfect than I was, which had all the perfections that I could imagine, and which was, in a word, God. To this I added that since I knew some perfections which I did not possess, I was not the only being in existence (I will here use freely, if you will pardon me, the terms of the schools), and that it followed of necessity that there was someone else more perfect upon whom I depended and from whom I had acquired all that I possessed. For if I had been alone and independent of anything else, so that I had bestowed upon myself all that limited quantity of value which I shared with the perfect Being, I would have been able to get from myself, in the same way, all the surplus which I recognise as lacking in me, and so would have been myself infinite, eternal, immutable, omniscient, omnipotent, and, in sum, I would possess all the perfections that I could discover in God.

For, following the reasoning which I have just explained, to know the nature of God as far as I was capable of such knowledge, I had only to consider each quality of which I had an idea, and decide whether it was or was not a perfection to possess

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

Descartes with Queen Christina of Sweden

it. I would then be certain that none of those which had some imperfection was in him, but that all the others were. I saw that doubt, inconstancy, sorrow and similar things could not be part of God's nature, since I would be happy to be without them myself. In addition, I had ideas of many sensible and corporeal entities, for although I might suppose that I was dreaming and that all that I saw or imagined was false, I could not at any rate deny that the ideas were truly in my consciousness. Since I had already recognised very clearly that intelligent nature is distinct from corporeal nature, I considered that composition is an evidence of dependency and that dependency is manifestly a defect. From this I judged that it could not be a perfection in God to be composed of these two natures, and that consequently he was not so composed. But if there were in the world bodies, or even intelligences or other natures that were not wholly perfect, their being must depend on God's power in such a way that they could not subsist without him for a single moment.

At this point I wished to seek for other truths, and proposed for consideration the object of the geometricians. This I conceived as a continuous body, or a space infinitely extended in length, breadth, and height or depth; divisible into various parts which can have different shapes and sizes and can be moved or transposed in

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

any way: all of which is presumed by geometricians to be true of their object. I went through some of their simplest demonstrations and noticed that the great certainty which everyone attributes to them is only based on the fact that they are evidently conceived, following the rule previously established. I noticed also that there was nothing at all in them to assure me of the existence of their object; it was clear, for example, that if we posit a triangle, its three angles must be equal to two right angles, but there was nothing in that to assure me that there was a single triangle in the world. When I turned back to my idea of a perfect Being, on the other hand, I discovered that existence was included in that idea in the same way that the idea of a triangle contains the equality of its angles to two right angles, or that the idea of a  sphere includes the equidistance of all its parts from its centre. Perhaps, in fact, the existence of the perfect Being is even more evident. Consequently, it is at least as certain that God, who is this perfect Being, exists, as any theorem of geometry could possibly be.

What makes many people feel that it is difficult to know of the existence of i God, or even of the nature of their own souls, is that they never consider things ; higher than corporeal objects. They are so accustomed never to think of anything without picturing it — a method of thinking suitable only for material objects — that everything which is not picturable seems to them unintelligible. This is also manifest in the fact that even philosophers hold it as a maxim in the schools that there is nothing in the understanding which was not first in the senses, a location where it is clearly evident that the ideas of God and of the soul have never been. It seems to me that those who wish to use imagery to understand these matters are doing precisely the same thing that they would be doing if they tried to use their eyes to hear sounds or smell odours. There is even this difference: that the sense of sight gives us no less certainty of the truth of objects than do those of smell and hearing, while neither our imagery nor our senses could assure us of anything without the co-operation of our  understanding.  

Finally, if there are still some men who are not sufficiently persuaded of the existence of God and of their souls by the reasons which I have given, I want them to understand that all the other things of which they might think themselves more certain, such as their having a body, or the existence of stars and of an earth, and other such things, are less certain. For even though we have a moral assurance of these things, such that it seems we cannot doubt them without extravagance, yet without being unreasonable we cannot deny that, as far as metaphysical certainty goes, there is sufficient room for doubt. For we can imagine, when asleep, that we

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

have another body and see other stars and another earth without there being any such. How could one know that the thoughts which come to us in dreams are false rather than the others, since they are often no less vivid and detailed? Let the best minds study this question as long as they wish, I do not believe they can find any reason good enough to remove this doubt unless they presuppose the existence of God. The very principle which I took as a rule to start with, namely, that all those things which we conceived very clearly and very distinctly are true, is known to be true only because God exists, and because he is a perfect Being, and because everything in us comes from him. From this it follows that our ideas or notions, being real things which come from God insofar as they are clear and distinct, cannot to that extent fail to be true. Consequently, though we often have ideas which contain falsity, they can only be those ideas which contain some confusion and obscurity, in which respect they participate in nothingness. That is to say, they are confused in us only because we are not wholly perfect. It is evident that it is not less repugnant to good sense to assume that falsity or imperfection as such is derived from God, as that truth or perfection is derived from nothingness. But if we did not know that all reality and truth within us came from a perfect and infinite Being, however clear and distinct our ideas might be, we would have no reason to be certain that they were endowed with the perfection of being true.

After the knowledge of God and the soul has thus made us certain of our rule, it is easy to see that the dreams which we have when asleep do not in any way cast doubt upon the truth of our waking thoughts. For if it happened that we had some very distinct idea, even while sleeping, as for example when a geometrician dreams of some new proof, his sleep does not keep the proof from being good. As for the most common error of dreams, which is to picture various objects in the same way as our external senses represent them to us, it does not matter if this gives us a reason to distrust the truth of the impressions we receive from the senses, because we can also be mistaken in them frequently without being asleep, as when jaundiced persons see everything yellow, or as the stars and other distant objects appear much smaller than they really are. For in truth, whether we are asleep or awake, we should never allow ourselves to be convinced except on the evidence of our reason. Note that I say of our reason, and not of our imagination or of our senses; for even though we see the sun very clearly, we must not judge thereby that its size is such as we see it, and we can well imagine distinctly the head of a lion mounted on the body of a goat, without concluding that a chimera exists in this world. For reason does not insist that all we see or visualise in this way is true, but it does insist that all our ideas or

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

notions must have some foundation in truth, for it would not be possible that God,  who is all-perfect and wholly truthful, would otherwise have given them to us. Since our reasonings are never as evident or as complete in sleep as in waking life, although sometimes our imaginations are then as lively and detailed as when awake, or even more so, and since reason tells us also that all our thoughts cannot be true, as we are not wholly perfect; whatever of truth is to be found in our ideas will inevitably occur in those which we have when awake rather than in our dreams.

Text from Discourse on Method, by Descartes, translated by J. Lafleur
 (New York: The Library of Liberal Arts, second edition, 1956), pp. 20-26.

The Philosophical Climate of Europe at the Time of Descartes

The times were beginning to find fault with the old traditions, the old language and literature, the old art, the old theological systems, the old political relations of Church and State, the old authoritative religion. The spirit of reflection and criticism, which had been silently quickening, broke out in open revolt against authority and tradition: in the revolt of nation against Church, of reason against prescribed truth, of the individual against the compulsion of ecclesiastical organisation. The conflict between Church and state had been settled in favour of the State, but within both Church and State themselves the desire for political, economic, religious and intellectual liberty was forming. It found partial realisation in the Renaissance and Reformation; later on it expressed itself in modem philosophy.

The history of this new era, the modern, is marked by a further awakening of the reflective spirit, a more insistent criticism and protest against absolutism and collectivism as represented by tradition. The need grew strong for freedom in thought, in feeling and in action. Reason became sovereign in science and philosophy. It was being increasingly accepted that truth is not something to be handed down by authority or decreed by papal bulls, but something to be acquired; something to be achieved by free and impartial inquiry. And the gaze was turned from the contemplation of supernatural things to the examination of natural things, from heaven to earth — theology finally accepted to yield her crown to science and philosophy. The physical and the mental world, society, human institutions, and religion itself were explained by natural causes.

What characterised the higher intellectual life of the period following the Middle Ages was an abiding faith in the power of human reason, an intense interest in natural things, a lively yearning for civilisation and progress. Knowledge, however, was esteemed and desired not only for its sake but also for its utility, for its practical value: for knowledge was power. Nearly all great leaders of modem thought, from Francis Bacon onward, were interested in the practical applications of the results of scientific investigation and looked forward with an enthusiastic optimism to a coming era of wonderful achievement in the mechanic art, technology, medicine, as well as in the field of political and social reform.

Proofs Of The Existence Of God And Of The Human Soul

Proofs Of The Existence Of God And Of The Human Soul

Modern philosophy, in its beginnings, breathed the spirit of the modem times, the characteristic of which we have endeavoured to describe. It was independent in its search for truth, resembling ancient Greek thought in this respect. It was rationalistic in the sense that it made human reason the highest authority in the pursuit of knowledge. It was naturalistic in that it sought to explain inner and outer nature without supernatural presuppositions. It was, therefore, scientific, keeping in touch with the new sciences, particularly with the sciences of external nature.

The new movement found in the work of Descartes its most significant formulation. He elaborated, for the future centuries, a method on which science and philosophy could found themselves confidently.

In looking back at the past, it is interesting for us to observe that we take our stand today on yet another frontier, perhaps as significant for the future as the preceding era was in its own time. Fresh discoveries of science are pointing the way to the elaboration of new methods. These have not yet been worked out but we seem to be outgrowing the past ones. Maybe, we shall be the innovators of those to come.

A few dates


Birth of Descartes.


Studies in the Jesuit College of La Fleche.


Night of great inspiration


Various travels through Europe.


Descartes settles in Holland.


Diccourse on Method.




The principles of philosophy.


Treatise on passions.


Descartes goes to sweden, invited by Queen Christina.


— Death of Descartes in Sweden.

Suggestions for further reading

Descartes, R. Meditations and Discourse on Method.

 Durant, Will. The Story of Philosophy. New York: Washington Square Press/Pocket Books.

 Russell, B. A. History of Western Philosophy. London: Unwin Paperbacks, Counterpoint Edition, 1984.

 Vrooman, Jack Rochford. Rene Descartes. New York: Putnam, 1970.

Proofs Of The Existence Of God And Of The Human Soul

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