René Descartes (1596-1650)
I. General Observations
René Descartes (picture) is justly considered the father of modern philosophy and the founder of the rational method as applied to philosophical research. In fact, he is the first philosopher to begin with the impressions which are in our intellect (intellectual phenomenalism) and lay down the laws which reason must follow in order to arrive at reasonably certain philosophical data.
This phenomenalism does not find its full development in Descartes. Indeed, Descartes reaches metaphysical conclusions which are no different from those of Scholastic philosophy. He maintains the transcendency of God, upholds human liberty and Christian morality.
But pantheism is sown deep in every form of immanentism. The rationalism of Descartes was to be quickly and logically bent in this direction by Spinoza, while other Cartesians, such as Malebranche and Leibniz, tried -- with less logic -- middle-of-the-road solutions between pantheism and the transcendence of God.
II. Life and Works
Descartes was born in 1596 at La Haye in France of a noble family, and was educated in the celebrated Jesuit college of La Flèche, where he received a philosophical and scientific education according to the principles of the Scholasticism of his day. Not fully satisfied with this first education, and urged on by a desire to better himself, he went first to Paris, and then enlisted in the army during the Thirty Years' War.
On the ninth of November, 1619, while still in the service in winter quarters, he gave himself up to meditating on how to apply the mathematical method of the sciences to philosophy. During this time he conceived the four laws which he described in his work Discourse on Method. He then abandoned the army, but before dedicating himself completely to philosophical meditation he undertook long travels throughout Europe.
In 1629 he retired to Holland, which offered him tranquillity for meditation and writing. He remained there until 1649. During these twenty years he wrote nearly all his books. In 1649 he went to the court of Queen Christina of Sweden, being summoned there by the Queen, who wished to study philosophy under his direction. Unable to resist the rigors of winter, he died in Sweden during 1650.
Descartes was a scientist and a philosopher. As a scientist he is noted for his studies in mechanics, physics and mathematics. As a philosopher he opened the period of modern philosophy.
Not all the philosophical works written by Descartes were published during his lifetime. His Rule for the Direction of the Mind was published posthumously, as was his treatise on The World.
The philosophical works published by the author were four: Discourse on Method; Meditations on First Philosophy, in which he proves the existence of God and the immortality of the soul; Principles of Philosophy, in four books, a systematic work reviewing the entire thought of the author; The Passions of the Soul, treating of the problem of morality.
III. The Laws of the Cartesian Method
Descartes, in his work Discourse on Method, after giving a criticism of the education which he had received (a criticism which is indirectly an attack on the Scholasticism of his day), goes on to set up the new method, according to him, must be the basis of all scientific and philosophical research.
These laws are four:
To accept nothing as true that is not recognized by the reason as clear and distinct;
To analyze complex ideas by breaking them down into their simple constitutive elements, which reason can intuitively apprehend;
To reconstruct, beginning with simple ideas and working synthetically to the complex;
To make an accurate and complete enumeration of the data of the problem, using in this step both the methods of induction and deduction.
To better understand these laws, we must note that for Descartes the point of departure is the ideas, clearly and distinctly known by the intellect -- the subjective impressions on the intellect. Beyond these clear and distinct ideas one cannot go, and hence the ultimate principle of truth consists in the clearness of the idea. Clear and distinct intuitions of the intellect are true. For Descartes, such clear and distinct intuitions are thought itself ("cogito") and the idea of extension.
Having arrived at this starting point (clear and distinct ideas), the intellect begins its discursive and deductive operation (represented by the second and third rules). The second law (called analysis) directs that the elementary notions be reunited with the clear and distinct ideas (the minor of the Scholastic syllogism). The third law (synthesis) presents them as the conclusion flowing from the premises. The final law (complete enumeration) stresses that no link in the deductive chain should be omitted and that every step should be logically deduced from the starting point (i.e., from the clear and distinct ideas). Thus, working from one step to the next, there will be achieved a system of truths all of which are clear and distinct, because all participate in the same degree of truth enjoyed by the first idea, which was clear and distinct.
This, as we know, is the method adopted in mathematics. Descartes transferred it to philosophy with the intention of finding clear and distinct concrete ideas, and of deducing from these, through reason alone, an entire system of truths which would also be real or objective.
The Aristotelio-Scholastic method (as well as that of classical realism in general) is also deductive, but it is very different from that of Descartes. Scholastic deduction is connected with objective reality because ideas are abstractions of the forms of the objects which experience presents. Thus both the concreteness of the ideas and the concreteness of the deductions based on these ideas are justified.
In Descartes ideas do not come from experience, but the intellect finds them within itself. Descartes declares that only these ideas are valid in the field of reality. Thus the concreteness (or the objective validity) of an idea is dependent upon its own clearness and distinction.
IV. Metaphysics: From Methodical Doubt to "Cogito Ergo Sum"
Descartes, as a result of the principles already established in his method, had first of all to seek out a solid starting point (a clear and distinct concrete idea), and from this opens his deductive process. To arrive at this solid starting point, he begins with methodical doubt, that is, a doubt which will be the means of arriving at certitude. This differs from the systematic doubt of the Skeptics, who doubt in order to remain in doubt.
I can doubt all the impressions that exist within my knowing faculties, whether they be those impressions which come to me through the senses or through the intellect. Indeed, I may doubt even mathematical truths, in so far as it could be that the human intelligence is under the influence of a malignant genius which takes sport in making what is objectively irrational appear to me as rational.
Doubt is thus carried to its extreme form. But notwithstanding this fact, doubt causes to rise in me the most luminous and indisputable certainty. Even presupposing that the entire content of my thought is false, the incontestable truth is that I think: one cannot doubt without thinking; and if I think, I exist: "Cogito ergo sum."
It is to be observed that for Descartes the validity of "Cogito ergo sum" rests in this, that the doubt presents intuitively to the mind the subject who doubts, that is, the thinking substance. In this, Cartesian doubt differs from that of St. Augustine ("Si fallor, sum"), which embodies a truth sufficiently strong to overcome the position of Skepticism. In Descartes, "Cogito ergo sum" is assumed, not only in order to overcome the Skeptic position but as a foundation for the primary reality (the existence of the "res cogitans"), from which the way to further research is to be taken.
This is the point which distinguishes the classic realistic philosophy from Cartesian and modern philosophy. With Descartes, philosophy ceases to be the science of being, and becomes the science of thought (epistemology). Whereas, at first, being conditioned thought, now it is thought that conditions being. This principle, more or less realized by the philosophers immediately following Descartes, was to reach its full consciousness in Kant and modern Idealism. (See: Meditations on First Philosophy, I and II; Discourse on Method, IV.)
V. From "Cogito" to the Proof of the Existence of God
The "cogito" reveals the existence of the subject, limited and imperfect because liable to doubt. It is necessary to arrive at an objective and perfect reality, i.e., to prove the existence of God.
Descartes makes use of three arguments which can be summarized thus:
"Cogito" has given me a consciousness of my own limited and imperfect being. This proves that I have not given existence to myself, for in such a case I would have given myself a perfect nature and not the one I have, which is subject to doubt.
I have the idea of the perfect: If I did not possess it, I could never know that I am imperfect. Now, whence comes this idea of the perfect? Not from myself, for I am imperfect, and the perfect cannot arise from the imperfect. Hence it comes from a Perfect Being, that is, from God.
The very analysis of the idea of the perfect includes the existence of the perfect being, for just as the valley is included in the idea of a mountain, so also existence is included in the idea of the perfect. (the argument of St. Anselm). (See: Meditations on First Philosophy, V; Discourse on Method, IV.)
Regarding the nature of God, Descartes ascribes to it more or less the same attributes as does traditional Christian theistic thought. In Descartes, however, these attributes assume a different significance and value. God, above all, is absolute substance: the only substance, properly so-called (hence the way is open to the pantheism of Spinoza). An attribute which has great value for Descartes is the veracity of God.
God, the most perfect being, cannot be deceived and cannot deceive. Thus the veracity of God serves as a guarantee for the entire series of clear and distinct ideas. They are true because if they are not true, I, having proved the existence of God, would have to say that He is deceiving by creating a rational creature who is deceived even in the apprehension of clear and distinct ideas. Thus, with the proof of the existence of God, the hypothesis of a malignant genius falls of its own weight.
Regarding the origin of ideas, Descartes holds that the idea of God, all primitive notions, all logical, mathematical, moral principles, and so forth, are innate. God is the guarantee of the truth of these innate ideas. Alongside these innate ideas Descartes distinguishes two other groups of ideas:
the adventitious, which are derived from the senses; and
the fictitious, which are fashioned by the thinking subject out of the former.
Both groups are considered of little worth by Descartes because they do not enjoy the guarantee of the divine veracity, and hence are fonts of error. Only innate ideas and the rational deduction made from them have the value of truth. (See: Meditations on First Philosophy, III.)
VI. The "Res Extensa" and the Mechanism of the Universe