One of the great fallacies of rationalism is its failure to take the fall of man seriously. Man's original sin is to try to be his own god, his own source of law, morality, and determination (Gen. 3:5). The Reformed view is that man is totally depraved as a result of the Fall, i.e., every aspect of his being is corrupted by his sin. This does not mean that fallen man is not capable of some limited good but rather that the ruling and over-ruling premise in his life is his will to be god, to supplant God and to efface His memory.
Now, if the Bible be true, we must agree with St. Paul that "the carnal mind is enmity against God: for it is not subject to the law of God, neither indeed can be" (Rom. 8:7). What we are told, first, is that fallen man's mind "is enmity against God." This certainly applies to the Scholastic view of the mind as well as Protestant rationalism. We are not told that the natural man's mind entertains enmity against God but that it is enmity against God in all its being. The evidence for this is its refusal to be subject to the law of God. Moreover, given the premise of the Fall, natural man's mind cannot be other than "enmity against God." The rationalist's premise is that reason can prove God's existence and vindicate His claims to fallen man, an impossible tenet.
We can neither presuppose that fallen man can be convinced of God's existence and law by reason nor can we assume a neutral stance on his part. But this is precisely what the rationalist tries to do. James Oliver Buswell, Jr., in A Christian View of Being and Knowing (1960), in criticizing Cornelius Van Til, insisted on the innocence of many unbelievers: "I know many unbelievers who are simply lost, bewildered, and in the dark" (James Oliver Buswell, Jr: A Christian View of Being and Knowing, p. 175: Grand Rapids, Michigan: Zondervan, 1960). It is a pity that Buswell did not notify God that He was in error in His judgments concerning fallen men! The Bible obviously needs revision if Buswell was right.
This is not a trifling matter. If the Bible is true about man, man's knowing is determined not by pure reason, but by his relationship to God. This means that pure reason does not exist, nor can man's reason function without reference to his relationship to God. As against all rationalistic philosophies, certain moral premises precede or undergird and condition all man's thinking. Is man the thinker at war with God, or is he at peace with Him? The thinking of John Dewey is not the thinking of Cornelius Van Til. We can concede that a non-Christian and a Christian are both good thinkers, but we must recognize that each begins with a different presupposition to argue to a logical conclusion.
The rationalist begins by placing himself outside time and history. His reason is supposedly objective and timeless. Of course, he may be in a chain of development, a Hume, a Hegel, a Dewey, or a Wittgenstein, but, somehow, for the rationalist, a philosophical rationalist transcends time to speak out of the clouds of being as the voice of logic. The rationalist begins with irrational premises about logic and reason.
Moreover, the rationalist insists on placing God Himself under the judgments of man's reason. E. J. Carnell wanted all revelations to meet the test of his reason. The arrogance of the Fall is in abundant evidence in rationalism.
The mind of man "is enmity against God" whenever and wherever it seeks to think without beginning with God. Whether they intend to or not, men put first things first, and the rationalist places his reason before God: he begins with reason, not with God.
The starting point of rationalism is more the Fall than it is reason. Its pride, arrogance, and neglect of the Biblical revelation is evidence of this. Cite the Fall and the noetic effects of sin to a rationalist and he derides it as not a rational argument while professing to be a Christian.
In recent years, humanistic rationalism has largely left philosophy. At the same time, it has flourished within the church. It is very much an Enlightenment survival and alien to theology in spirit.