Lesson 3: Founding the Modern Project: Cartesian Doubt

A. Basic Themes

Rene Descartes and the Mastery of Nature

Rene Descartes (1596-1650) outlined the philosophy which gave a charter to the growth of experts in society in his Discourse on Method. Rejecting the ancient philosophy for its lack of effective control, Descartes says that he wishes to found a new practical philosophy; by "knowing the force and actions of the fire, water, air and stars, the heavens, and all other bodies that surround us, just as we understand the various skills of our craftsmen, we could make ourselves the masters and possessors of nature" [1]. We are now approaching the fulfilled dream of Descartes' modern project. For Descartes promised as the fruit of his new philosophy, "an infinity of devices that would enable us to enjoy without pain the fruits of the earth and all the goods one finds in it, but also principally the maintenance of health." In order to reach this goal Descartes recognized the need to reform the entirety of education and the social role of the intellectual in society such that expertise would be more readily developed and experts be revered as great benefactors who are free to pursue their study. He evaluated the curriculum of studies in terms of the certitude and utility: he sought "a clear and assured knowledge useful for life." Poetry, theology, philosophy, ethics and a few other disciplines were cast aside in light of these new criteria of certitude and utility. In fact, the disciplines that would lay the basis for the experts, scientific studies, would have to be built from the ground up. On the basis of mathematical science, Descartes proposed his famous new method for the conduct of inquiry. It would begin with a universal doubt of anything not clear and distinct; again, traditional opinion would be swept aside in all areas in order to make room for the useful and certain knowledge of science. The certitude of science would be assured by the use of simple nature and forms such as principles of mechanics. In its streamlined form, the method for arriving at knowledge would follow the analytical method, breaking apart a problem into its simplest terms and then building up to greater level of complexity. Descartes' project and method have been tremendously successful.

But its success is marred by an ambiguity about its goal or purpose. For when Descartes turned to human production he praised projects that followed a rational and effective plan, whatever their end. For he admits that in the political order he must admire Sparta even if its ends or purposes were not sound. At least they were organized effectively. The crack in the system appears here. For the end is not subject to the same clarity as the method. The end is left ambiguous since it is not within the competence of the new science to determine it; as Richard Kennington puts it, "the utility goal can never be brought within the charmed circle of certitude" [2]. Descartes simply adopts the lowest common denominator by appealing to that which is most universally desired: health and life and convenience of living. To cite Kennington again, "the benefits are as universally available to humanity as they are devoid of exacting duties or self-sacrifice." But this begs the question about the nature of the good life. The technical skills appear to be neutral to an end; but in fact they point to one end and encourage us to judge in terms of a utilitarian and hedonistic ethic.

The charter for the reign of the expert derives from Cartesian philosophy. Its goal is mastery of nature and it appears humanitarian as it seeks to provide human convenience. The criterion for the new knowledge is certitude which entails skepticism towards traditional modes of opinion and grants to the expert a special status. The method is not only inherently set against tradition and opinion, it requires a reductive approach to the material in the name of "objectivity." And it further requires specialization and a narrow or partial vision in the name of competence. Most of all, the Cartesian project is problematic because of the ambiguity about the end or purpose. On the one hand the expert must appear neutral; for the question of end or purpose is beyond his competence. This is the contradiction at the heart of the project. Every technique is put to use for some end, but the end is not determined by a technique. The expert easily assumes an end for technique by appealing to what people want. Thus, on second look, the expert appears as a humanitarian who simply appeals to universal human desires and passions. The expert is therefore unproblematic. But when it is seen that the method requires a reductive approach and that it encourages the lowering of human goals, it becomes problematic in the extreme. The reductive approach to human affairs is potentially dehumanizing and degrading. It may well lead to the "abolition of man" [3].

1. Rene Descartes, Discourse on Method, trans. Donald A. Cress (Indianapolis: Hackett, 1985). See Richard Kennington, "Rene Descartes," in History of Political Philosophy, eds. Leo Strauss and Joseph Cropsey, 3rd ed. (Chicago: Univ. of Chicago Press, 1987), 421- 439.

2. Richard Kennington, "Descartes and the Mastery of Nature," in Organism, Medicine, and Metaphysics, ed. S. F. Spicker (Dordrecht, Holland: D. Reidel, 1978), 212.

3. See C. S. Lewis, The Abolition of Man (New York: Macmillan, 1947), 80-91. See Michael D. Aeschliman, The Restitution of Man: C. S. Lewis and the Case Against Scientism (Grand Rapids: Eerdmans, 1983). Peter Kreeft, C. S. Lewis for the Third Millenium (San Francisco: Ignatius Press, 1994).

B. Outlines and Study Guides

1. Descartes Basics

  • EFFECT: BRAVE NEW WORLD- technological society

2. Study Guide - Descartes Discourse On Method

    PART 1
  • 1. What is the most evenly distributed commodity in the world?
  • 2. What is the origin of the diversity opinions?
  • 3. Is it enough to have a good mind? Explain.
  • 4. What is Descartes' purpose in writing?
  • 5. What did Descartes expect to get from education on "letters"?
  • 6. By what was Descartes embarrassed?
  • 7. Make a list of the benefits and problems with each of the following disciplines he studied in school: language (travel), fables, histories, great books, poetry, math, morals, theology, philosophy, law and medicine, science
  • 8. What did Descartes learn in his travel about the truth of how people reason?
  • 9. What else did he learn from travel about custom?
    PART 2
  • 10. Where is perfection found in a house, a city, a state?
  • 11. Why does he admire Sparta?
  • 12. How does Descartes apply the same principle to learning?
  • 13. Does he claim to be a reformer? Explain.
  • 14. What are the four principles of his method?
    PART 3
  • 15. Why does Descartes counsel an attitude of "going along"? In everything or are there limits?
  • 16. What is Descartes' ideal of virtue?
  • 17. What is the Stoic maxim? Does Descartes agree with it or not? Explain.
    PART 6
  • 18. Why did Descartes decide to publish his method and book?
  • 19. What kind of philosophy was taught in the schools? What kind of science is the new science taught by Descartes? To what end does it lead? Why is this desirable? What will be the chief science? Why?

3. Study Guide On Descartes Meditations

Meditation I
  • Characterize the Cartesian approach to tradition and beliefs inherited from the past.
  • Why does Descartes have some doubt about the senses? Is there a disproportion or hyperbole?
  • Why does Descartes have some doubt whether he is sitting by the fire?
  • Why does Descartes have some doubt whether he is really awake? I.e. what is a dream?
  • Interpret this method of doubt in light of the dualism of modern science and "the similarity thesis."
  • Explain the analogy of a painter painting images of sirens and satyrs - what is real? How does this apply to world of senses, i.e. what is real or "simple and more universal."
  • Why does Descartes even doubt the world of science and mechanism compared to arithmetic and geometry?
  • What does Descartes say about a powerful God? Does he say that God is supremely good?
  • How does this belief place in doubt even mathematics?
  • How does he treat this belief in God and God's nature? Why?
  • Describe the evil genius. On his supposition what is eliminated? Does anything remain?
  • What is the one thing that is within the philosopher's power?
  • How is the Cartesian philosopher likened to "a captive who in sleep enjoys an imaginary liberty"?
Meditation II
  • How is the Cartesian philosopher like "a man in very deep water," i.e. a deep whirlpool?
  • What is the only certain truth? Why is Archimedes invoked?
  • How is the truth of self discovered?
  • What is the next question after self-discovery?
  • What did he formerly believe himself to be? Why does he now doubt that? What kind of thing can he say that he is with certitude?
  • Why is imagination excluded? This is about order of knowing - not being.
  • What activities can a "thinking thing" perform?
  • What is the true thing to say about imagining, feeling, sensing?
  • Explain idea of "free rein" and "regulation."
  • Recount his meditation and reflection on a piece of wax - what do senses, imagination and mind tell him? Which tells truly? Explain.
  • What is the deepest or most certain truth revealed by reflection on the piece of wax? Explain.
  • What does Descartes no longer distinguish?


1. Jacques Maritain, The Dream of Descartes

Jacques Maritain, The Dream of Descartes London 1946

From beneath the stern and mighty brow of Descartes shine two living truths, two precious truths - one that is old, the other new. The latter is the young truth of physico-mathematical science [Galileo], the former is the ancient truth, the Socratic and Christian precept: Go back into thyself and into the spiritual element which is within thee. . . . Perceived more or less confusedly, these truths fascinated and deceived the seventeenth century.

2. The Ancient Knowledge is Useless

"It is possible to attain knowledge which is very useful in life, and instead of the Speculative knowledge of the Schools, we may find a practical philosophy by means of which, knowing the force and action of fire, water, air, the stars, the heavens and all other bodies which environs us, as distinctly as we know the different crafts of our artisans, we can in the same way employ them in all those uses to which they are adapted, and thus render ourselves like the masters and possessors of nature. ... to have the fruits of life without pain ... principally, health." Rene Descartes - Discourse on Method D6

"I always had an excessive desire to learn to distinguish the true from the false, in order to see clearly in my actions and to walk with confidence in this life."

3. The Ancient Knowledge is Dubious

"No single thing is to be found in it which is not subject of dispute, and in consequence which is not dubious." Rene Descartes - Discourse on Method

"But as regards all the opinions which up to this time I had embraced I thought I could not do better than endeavor once for all to sweep them completely away, so they might later be replaced, either by others which were better, or by the same, when I had made them conform to the uniformity of a rational method or scheme." Rene Descartes - Discourse on Method

Certain and Useful Knowledge: Mathematical Physics, "A Geometry of the World."

"Most of all was I delighted with Mathematics because of the certainty of its demonstrations and the evidence of its reasoning; I did not yet understand its true use ... I was astonished that, seeing how firm and solid were its foundations, no loftier edifice had been reared thereupon." Rene Descartes - Discourse on Method

4. Jacques Maritain on the effects of Descartes' Philosophy

What fruits did this germ bring forth? To determine them one would have to survey the whole of Descartes' systems. I shall here confine myself to three principal aspects of it; the first, which concerns the connection between thought and being; the second, the intellectual hierarchies and the meaning of knowledge; the third, the conception of man.

From this first point of view, it is idealism that we owe to Descartes; from the second, it is rationalism; from the third, Cartesian dualism.

If it is the question of the connection between thought and being, I shall simply recall (in order not to become involved in discussions of too-technical a nature) -- that for the Scholastics we communicate with things first by means of the senses which attain the thing itself existing outside of us, not in its intimate nature but in its action upon us; and then by means of the intellect and of ideas -- ideas which are drawn actively from the senses by the mind, and which are essentially immaterial means, living and vital relations by which we get at what things are, at their natures.

Thus, whereas divine knowledge precedes things and measures them, since it makes them, our own knowledge is measured by things; and the least thing, the tiniest grain of wheat is a resisting, consisting, subsisting reality, the intelligibility of which we shall never have ceased to drain.

For Descartes, on the contrary, the senses have no knowledge value; they have only a pragmatic value. And ideas are not only means, they are already things; it is as things that they are attained by thought (now conceived only as self-consciousness) -- as if they were pictures which it discovers in itself. Locke's formula, ideas are the immediate objects of thought, is a pure Cartesian formula. Idea-pictures, idea-screens. In short, we know only our ideas; thought has direct contact only with itself.

Descartes, no doubt, does not stop there. He still believes in things, he wants to know them. You know to what device he has recourse in order to justify that knowledge. Cogito, my thought seizes upon itself and grasps its own existence. In this thought there is the idea of God; from the idea of God I conclude that God exists: God existing and being veridical, the clear and distinct ideas which I find in me, like innate pictures and like objects immediately attained by my thought, these idea-pictures are good; back of them are models, doubles, which are things. Thus I am certain that this table exists, and I am sure of the truth of the propositions that I can set forth on the subject because, first of all, I'm sure of my thought and sure of the existence of God, through whom I must pass in order to be sure of anything, and who is the Guarantor of my science, of the Science.

There you have the Cartesian circuit. Modern philosophy will not be long in pulling it to pieces -- from that point of view it is like the primitives according to Freud; it has killed and eaten its father, it has devoured Descartes. It is clear, for example, that the whole system remains in the air because one simply does not demonstrate the existence of God by starting with the sole idea of God.

What is left then, is not the Cartesian system, it is the Cartesian conception of thought and ideas. Whether one believes in the existence of things as Descartes himself believed (thanks to the circuit in question), or as Spinoza did (to the extent that he was a realist) in saying that there is a parallelism between the thing and the idea, and that the order and the connection of ideas are identical to the order and connection of things, the fact remains that the modern conception of knowledge itself is from the very outset idealistic.

Thought directly attains only itself; it is not ruled by things, but by its own internal exigencies; it does not depend on things but on itself alone. A world shut up, absolute -- by itself alone it develops science within itself, without measuring its strength against any extraneous resistance. There it is, a human knowledge like divine knowledge, a knowledge which depends only upon itself. When the great modern idealists, Kant and his successors, make their appearance, they will make Cartesian root produce its natural fruit.

What is the cultural significance of idealism? It carries along with it a sort of anthropocentric optimism of thought. Optimism because thought is a god, who unfolds himself, and because things either conform to it, or do not even exists apart from it. What drama could possibly occur? Either there is no being to set off against thought, or there is only being completely docile to thought. An optimism which is anthropocentric, because the thought in question is the thought of man; it is around human thought that objects revolve. All is well for that thought; and all will be better and better.

But this optimism is, if I may say so, committed to suicide; for it presupposes a rupture with being, and finally, in spite of Descartes' personal intentions and in spite of the efforts of his immediate successors, it supposes an eviction of the ontological. There we have the great, the primordial Cartesian break. Man shut up within himself is condemned to sterility, because his thought lives and is nourished only upon the things that God has made. Man the center of an intelligible universe which he has created in his own consistence, for his consistence is to be the image of God. He is in the middle of a desert.

Let us consider now another aspect of the Cartesian revolution, the aspect which concerns the intellectual hierarchies and the meaning of knowledge.

Human reason is Reason in itself, Reason in its pure state. A universal rule and measure, all things must be adjusted to its level. It is no longer measured, it measures, it subjugates the object. Even the adversaries of rationalism like Pascal have, in the seventeenth century, this absolutist conception of reason. Descartes formulated its philosophy.

Descartes did not invent evidence as textbooks believe, but he completely changed the meaning of the word. Evidence is no longer a property of the thing; that is, its radical intelligibility blossoming in the mind and imposing itself on us in the judgment we bring to bear upon the thing. It becomes a property of the ideas, of the idea picture which we contemplate in our thought. There are self-evident ideas; they are clear and distinct ideas, the ideas of what Descartes called simple natures. To know is to reduce everything to these clear and distinct ideas, to break up the object into these atoms of evidence.

In reality we are not born with those atoms of evidence in us. The clear and distinct ideas will, in fact, be easy ideas, the most conveniently manageable and communicable representations, the elements of a mechanical reconstruction of reality. We can see how, from the Cartesian short-cut for arriving at wisdom, people will pass on to the philosophy of enlightenment.

We can see especially how it was that evidence, for the ancients, being in the last analysis the manifestation of a mystery (that is, of the root intelligibility of created things imposing itself on our mind by becoming luminous within it), a sort of natural relationship existed for them between intelligence and mystery. On the one hand then, in order to avoid the absurd and to remain faithful to the very first evidence -- that of sense perception and that of the principle of identity, science itself and philosophy had to recognize a mystery of relative unintelligibility or ontological obscurity in things; that is, potentiality in Aristotle's meaning of the word, witnessing that the created is not God, who is the pure Act of intelligibility.

On the other hand, human knowledge had to recognize at the summit of things, a mystery of superintelligibility, that of the spiritual realities and above all, of God. And if God revealed to us in the obscurity of faith something of Himself, the intellect could and even should make every effort to penetrate as far as possible these revealed truths, and to grasp their concatenation, even though it cannot have the evidence of their principles. A science of the mysteries is possible: a science of what is not evident for us, but is infallibly believed on the authority of the first Truth -- that is theology. And Christian intelligence could say with St. Lawrence: "My night allows the light to enter," mea nox obscurum non habet.

Thus the whole movement of intelligence was holy, consecrated, because it was orientated toward God. Philosophy itself was Christian, secular knowledge was Christian. As a matter of fact, philosophy by its very object is quite distinct from faith and from theology. It is strictly of the natural and rational order. But in the subject in the human soul it is fortified and illuminated by the superior virtues with which it is in vital continuity, integrated to the great movement of love which carries the soul toward the vision of its Creator.

With Descartes, everything changes. This distinction achieved in coherence and dynamic solidarity becomes separation, isolation -- and soon even opposition. Philosophy is sufficient absolutely and unto itself alone in the soul; not only is its object of the natural order, but to all intents and purposes it demands that its subject as such be cut off from all supernatural life, cut off from itself as Christian. Hence is explained the absurd myth from which we are still suffering, of a man presumably in the state of pure nature in order to philosophize, who crowns himself with grace in order to merit heaven. The crown will not be long in falling away like a useless accessory. The man of nature -- of fallen nature -- will remain. The Cartesian revolution has been a process of secularization of wisdom.

As evidence for Descartes is a quality of our ideas -- ideas which constitute science only if they are purely and absolutely luminous, and which we should sort out in order to discard everything that is obscure -- a total antinomy exists henceforth between intellection and mystery. On one hand, the pure geometrical light and the pure light of the cogito; on the other, an impenetrable darkness. From the world of matter, which is beneath thought, thought must drive out absolutely all obscurity. Above all, it must acknowledge the obscurity of things divine; but woe to it if it tries to venture there.

Let us briefly characterize these two series of consequences of the Cartesian position.

On the side of what is superior to man, Descartes was too intelligent to deny mystery. He deepened it rather; he made everything, even science itself, appendant to God, and to His incomprehensibility, the sovereign guarantee of the value of understanding and of clear ideas.

But what remains, and what is essential to the whole future of thoughts, is that a science of mystery is henceforth impossible.

We know that in matters of religion Descartes was a fideist; he was, as he said, of the religion of his king and of his foster-mother. This fideism was accompanied by a violent antitheologism. In short, Descartes denied the possibility of theology as science; the only science, the only wisdom, was it not natural wisdom -- philosophy? A century and a half later Kant, as though to punish that pride, will deny in his turn the possibility of metaphysics as science. Contempt for theology, that is, for the most exalted use that man can make of speculative reason, in familiarizing it with things pertaining to deity -- contempt for theology was the first resignation, and the first betrayal, of Christian intelligence.

Concerning metaphysics itself, Descartes left an insoluble contradiction as a legacy to modern thought. On the one hand, in order that the knowledge of the existence of God may be the most certain of all knowledge, the idea of God must be a clear idea in the Cartesian system, the clearest and most distinct idea of all -- an intellectual intuition. Here we have modern thought launched in the direction of ontology and of pantheism. On the other hand, the infinite is in no way intelligible to us; it is vain to speculate upon it; no science of it is possible. And there we have modern thought launched toward agnosticism. Pantheism, agnosticism, it will ceaselessly swing back and forth between the two terms of this contradiction.

To tell the truth, Descartes did not trouble himself much over the speculative conciliation of such a contradiction, as he constantly broke up the harmonies of philosophia perennis into two antinomic errors, each one disguising the other. He needs God as the guarantor of science; therefore he betakes himself to Him by the quickest route, one which most resembles an intuition: to know that He exists and that He guarantees the human order. Reassured of it as a practical man, he loses interest in God; it is the world which interests him now. He turns aside religiously from God. Too exalted a God! Too sublime. Let us pay our respects to the Creator with dispatch. And now, bring on the world. If reason were to linger over things divine, it could only be in order to submit them to itself, since to know, for Cartesian reasoning is to subjugate the object. A sacred flight precipitates it toward things below.

And this is what matters to us: the overturning of the intellectual order, the inversion of the impulse of knowledge, for which Descartes is doubtless not the first one responsible, but as it were the prince and legislator. Metaphysics is reduced to a justification of science; it has as its aim to make physics possible.

Aristotle said that there is more joy in knowing divine things imperfectly and obscurely than in knowing perfectly the things proportioned to our minds. And thus the nature of our intellect is to drag along toward divine things. Descartes on the contrary, boasted of devoting only a very few hours a year to metaphysical thoughts. In his eyes, it is important "to have thoroughly understood once in one's life the principles of metaphysics," but "it would be very harmful to occupy one's understanding in meditating upon them, because it would then be unable to attend to the function of the imagination and the senses as well. Cartesian understanding does not drag itself along toward things divine, it settles comfortably in worldly things. Cartesian science is by essence a rich man's, a propertied man's science. What is, first of all, important to him is not the dignity of the object, even though it be obtained only through certainty not luxurious means -- what is important to him is the perfection of the means, it is the comfort of clear ideas.

With regard to what is inferior to man, to the world of corporeal nature, Cartesian intellect claims to understand everything exposed to the core, through the substance, through the essence itself. Matter lies naked before it as before the angels. The mathematical knowledge of nature, for Descartes, is not what it is in reality, a certain interpretation of phenomena, invaluable moreover, but which does not answer questions bearing upon the first principles of things. This knowledge is, for him, the revelation of the very essence of things. These are analyzed exhaustively by geometric extension and local movement. The whole of physics, that is, the whole of the philosophy of nature, is nothing but geometry.

Thus Cartesian evidence goes straight to mechanism. It mechanizes nature, it does violence to it; it annihilates everything which causes things to symbolize with the spirit, to partake of the genius of the Creator, to speak to us. The universe becomes dumb.

And why all this? What is the end of all our effort to know? It is a practical end: to become, as Descartes puts it in the Discourse on Method, masters and possessors of nature. To desire to dominate and utilize material nature is a good thing! But once the direction of knowledge was reversed, as I remarked a while back, this practical domination created force was to become two centuries after Descartes, the final aim of civilization -- and that is a very great evil.

The cultural significance of rationalism thus becomes clearly apparent to us. It implies an anthropocentric naturalism of wisdom; and what optimism! It is a doctrine of necessary progress, of salvation by science and by reason; I mean, temporal and worldly salvation of humanity by reason alone, which, thanks to the principles of Descartes, will lead man to felicity, to "that highest degree of wisdom in which the sovereign good of human life consists" (he wrote it himself in the preface to the French translation of the Principles)-in giving man full mastery over nature and over his nature; and, as the Hegelians were to add two centuries later, over his history. As if reason by itself alone was capable of making men act reasonably and of securing the good of people! There is no worse delusion.

On the balance-sheet we should inscribe: rupture of the impulse which was directing all the labor of human science towards the eternal, toward conversation with the three divine Persons -- upsetting to the élan of knowledge. Knowledge does not aspire to do more than give man the means of domesticating matter. The sole retreat remaining for the spiritual will be science's reflection upon itself. And doubtless, that is indeed something of spiritual but of an autophagous spiritual. To delude oneself with the thought that the idealistic ruminating of physics and mathematics is enough to force the gates to the kingdom of God, to introduce man to wisdom and to freedom, to transform him into a fire of love burning for all eternity, is psychological childishness and metaphysical humbug. Man becomes spiritualized only by joining with a spiritual and eternal living One. There is only one spiritual life which does not mislead -- that which the Holy Spirit bestows. Rationalism is the death of spirituality.

Then it is through the experience of sin, of suffering and despair that in the nineteenth century we will see spirituality reawaken in the wilderness: through a Baudelaire, Rimbaud. An ambiguous spirituality, good for heaven if grace takes hold of it, good for hell if pride interferes. Many of our contemporaries will seek nourishment for their souls in anti-reason, and below reason, nourishment which should be sought only above reason. And to have led so many reasoning animals around to a hatred of reason is another of rationalism's misdeeds.


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