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Descartes and Rationalism

Rationalism has ancient roots, but, in its modern form, it stems very clearly from Rene Descartes (1596-1650). Some would object to placing Descartes in the ranks of men whose work was damaging to the Faith, but Descartes' formal church adherence is no more conclusive than Ivan the Terrible's obvious allegiance to the Russian Orthodox Church.

R. J. Rushdoony
  • R. J. Rushdoony
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(Note: This is in a sense a continuation of Position Paper no. 209 on "Reason and Rationalism.")

Rationalism has ancient roots, but, in its modern form, it stems very clearly from Rene Descartes (1596-1650). Some would object to placing Descartes in the ranks of men whose work was damaging to the Faith, but Descartes' formal church adherence is no more conclusive than Ivan the Terrible's obvious allegiance to the Russian Orthodox Church.

J. Hillis Miller, in The Disappearance of God (1963) and Poets of Reality (1965) called attention to the importance of Descartes to the modern mind. Descartes' starting point in philosophy was cogito, ergo sum, I think; therefore I am. Self-consciousness was for him the primary reality. Things exist, Descartes held, simply because I think them. As God said, Let there be, and there was, i.e., the universe came into being, for Descartes reality began with his thinking of things. Man is the center, the great subject, and everything else is an objectif validated by man's thinking. God then becomes one object among many, an object requiring validation by man's thinking in order to become real. Man can thus "create" God or will "the death of God." For this reason, the death of God thinkers of c. 1970 did not concern themselves with whether or not the Biblical God existed "out there." For them, the important question was for their minds the fact that He was no longer real to them, and therefore He was dead.

Immanuel Kant developed Descartes' implications fully and clearly. In the "Preface to the Second Edition" of his Critique of Pure Reason, Kant wrote:

Hitherto it has been assumed that all our knowledge must conform to objects. But all attempts to extend our knowledge of objects by establishing something in regard to them a priori, by means of concepts, have, on this assumption, ended in failure. We must therefore make trial whether we may not have more success in the task of metaphysics, if we suppose that objects must conform to our knowledge.

(Immanuel Kant: Critique of Pure Reason, p. 16 of the Norman Kemp Smith trans., 1934)

The logic of this leads to the Hegelian premise that the rational is the real, i.e., the mind of the creator of reality. In this logic, man makes God, not God man. In Biblical terms, trying to prove the existence of God by reason is like trying to find the sun on a hot, clear summer day by lighting a match.

But, in Cartesian rationalism, man was now the creator and God the created one. In the existentialist development of this rationalism, true knowledge and true existence required the discarding of all knowledge from the past, parents, church, and society, and a pure dependence on the moment. Jean-Paul Sartre could hold, in Being and Nothingness, that, between a philosopher-prime minister who was an existentialist, and the town drunk, the drunkard was the better existentialist because he depended on none for his thinking.

Existentialism has stressed the moment because nothing else is real. It cuts itself off from the past, and by denying God, it denies consequences because the rationality of man is alone determinative, not past events, nor God. As a result, there is also no future because self-created man is severed from past and future, from consequence, and lives in the psuedo-eternity of the moment.

Cornelius Van Til often pointed out that rationalism ends in irrationality because it has ultimately nothing left other than man and his self-consciousness, man as the center and subject who decrees the existence of men and things only when he chooses to recognize and "prove" them. 

It is interesting to note how many of the prominent philosophers since Descartes have not been married. Marriage is disruptive of the monotheistic isolation of the new god, man as the subject and center. (There are hints from history that Socrates was a very poor husband!)

Herbert Ernest Cushman, in A Beginner's History of Philosophy, Vol. II (1911), wrote of Descartes' philosophy, "It spread over Europe in a somewhat similar way to the Darwinian evolution theory in modern times" (p. 80). It was "obvious truth" to men, and like Darwin's theory, no proof was needed. Moreover, according to Cushman, Descartes "demanded the same return to an uncorrupted mind for understanding that Rousseau many years later demanded for the heart" (II, 70). Descartes' view of the mind or reason was of an unfallen entity whose judgments are final, and this is basic to all rationalism and exposes its non-Christian character. Moreover, Descartes changed the definition of reality: "For Descartes reality lies within the Self" (II, 72). While at times Descartes used Christian terms, described God as the only substance, and man as created, the basic direction of his thinking was to place man at the center, and reason or consciousness as the final judge.

We now live in the death throes of Cartesianism, and sadly, too much of the world, Christian and non-Christian, is Cartesian. Modernists and fundamentalists alike reflect Descartes. To make man, the self or the soul, the ultimate center of religion and religious activity is to deny our Lord's words in Matthew 6:33 and to forget the Kingdom of God.

The Cartesian influence has stripped both theology and morality of meaning to center emphasis on man's reason, or his soul, or his self, as the case may be. Cartesianism has shriveled the world, as also men's souls. By exaggerating man's powers, it has deformed and limited man.

It is important for Christians to break with Descartes and all forms of rationalism, and to follow the superb Reformation view of Cornelius Van Til.


R. J. Rushdoony
  • R. J. Rushdoony

Rev. R.J. Rushdoony (1916–2001), was a leading theologian, church/state expert, and author of numerous works on the application of Biblical law to society. He started the Chalcedon Foundation in 1965. His Institutes of Biblical Law (1973) began the contemporary theonomy movement which posits the validity of Biblical law as God’s standard of obedience for all. He therefore saw God’s law as the basis of the modern Christian response to the cultural decline, one he attributed to the church’s false view of God’s law being opposed to His grace. This broad Christian response he described as “Christian Reconstruction.” He is credited with igniting the modern Christian school and homeschooling movements in the mid to late 20th century. He also traveled extensively lecturing and serving as an expert witness in numerous court cases regarding religious liberty. Many ministry and educational efforts that continue today, took their philosophical and Biblical roots from his lectures and books.

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