Van Til describes his own epistemology as rooted in "analogical knowledge." The reader may call to mind the use of such language within the Thomist discussion of religious language. For Aquinas, knowledge was either equivocal, univocal or analogical.
It is difficult to overstate the importance, however, of being cognizant of the fact that Van Til's theory of analogical knowledge is most emphatically not Thomist. Indeed, Van Til believes that his own distinctly Augustinian understanding of analogical knowledge is diametrically opposed to that of Aquinas:
The Scholastics made the same mistake as the Greeks. Both took for granted that words must be used either simply univocally or simply equivocally. Both took for granted that every predicate used must apply to God in the same way that it applies to man or there can be no meaning in any predication at all. It is possible to produce quotations from Aquinas and the other Scholastics which seem to assert the contrary of this. Aquinas speaks of the necessity of analogical reasoning. But the point is that he is not consistent in this. He constantly reverted to the Greek position that it is reasonable and possible for man to engage in the attempt to solve these antinomies. Moreover, what Aquinas means by analogical reasoning is based upon the Aristotelian notion of analogy of being. This notion implies that the abstract rationality of Parmenides and the abstract diversity of Heraclitus are involved in one another. The Thomistic notion of analogical knowledge is therefore the direct opposite of the idea of analogical knowledge inherent in Augustine’s latest thinking. Augustine’s notion of analogy presupposes the biblical teachings of the Trinity, of creation, and of redemption, while the Thomistic notion of analogy is built on Aristotelian philosophy and, therefore, excludes these biblical presuppositions(Van Til).
For Van Til, the error of Aquinas has to do with his dependence upon the abstract categories of Aristotelian and Scholastic philosophy rather than the concrete Person of the Trinity, and the biblical realities flowing from that Person. Van Til is not interested in medieval debates that are far removed from the Bible. Indeed, Van Til likewise rejects Aquinas as inconsistent because Aquinas at one point pays lip service to analogical being and therefore to analogical predication, but at other points attempts to provide solutions to biblical antinomies that are comprehensible to man, when it is precisely Van Til's point, as we will see, that for something to be an antinomy, by definition, means that only God can understand its solution. Man can never understand it, simply by virtue of the Creator/creature distinction: "...there can be no true analogical reasoning as long as the material universe or anything else that is finite be thought of as existing except as created by God"(Van Til). The dependence of all creation upon the concrete Person of the Triune God, as we will see, constitutes an essential element of why Van Til believes that analogical reasoning necessarily follows in the Christian worldview.
As we have said before, rather than depending upon Aquinas for his definition of what constitutes analogical reasoning, Van Til draws his understanding of what constitutes analogical knowledge from Augustine's Trinitarian philosophical theology:
We may contrast this doctrine of the Trinity with Plato’s thought by calling attention to the fact that for Augustine the Trinity furnished the basis of the principles of unity and diversity in human knowledge. In other words the Trinity is for Augustine as for all orthodox Christians a conception without which knowledge were impossible to man. That there is plurality which man must seek to relate to some underlying unity, is patent to all men. From the earliest dawn of reflective thinking it has been the effort of man to find unity in multiplicity. But the difficulties that meet one when trying to speculate upon the question of unity and plurality are that if one begins with an ultimate plurality in the world, or we may say by regarding plurality as ultimate, there is no way of ever coming to an equally fundamental unity. On the other hand, if one should begin with the assumption of an ultimate abstract, impersonal unity, one cannot account for the fact of plurality. No system of thought can escape this dilemma. No system of thought has escaped this dilemma. Many systems of thought have denied one of the horns of the dilemma, but all that they have accomplished by doing this is to find relief in the policy of the ostrich(Van Til).
For Van Til, Augustine demonstrated that only in a Trinitarian world could man coherently relate the diversity of experience to some underlying unity. Monadic theists are unable to account for the diversity of experience, and pluralists are unable to account for the unity of experience or relate it to an underlying unity without which knowledge is impossible.
Although in the doctrine of the Trinity the solution to how plurality is to relate to unity is resolved, man himself is unable to understand this resolution. Indeed, it is essential for Van Til that, although God does understand the solution, man is unable to understand it. Its very status as a solution, puzzling though this may sound, depends on its inability to be understood by man by virtue of the fundamentally mysterious nature of God's Triunity.
This analogical understanding of knowledge applies not only to knowledge of God, but to knowledge of the universe. Indeed, for man to know anything the way God knows it would mean that God would no longer be God. Van Til believes not only that all knowledge is analogical in this way, but that only analogical knowledge is true knowledge. Van Til goes on to elaborate on the metaphysical ground of what makes man's knowledge necessarily analogical: "It is analogical because God’s being unites within itself the ultimate unity and the ultimate plurality spoken of above. And it is true because there is such a God who unites this ultimate unity and plurality. Hence we may also say that only analogical knowledge can be true knowledge"(Van Til).
The reason Van Til believes that knowledge must be analogical is because of the incomprehensibility of the metaphysical ground of the solution to the relation between plurality and unity in the universe. Since God is the ground of the being of all things, on whom the whole universe is dependent, and since this includes knowledge, it follows that if our knowledge terminates on a Person in whose being the incomprehensible solution to the aforementioned philosophical problem resides, our knowledge must be analogical because the source of knowledge cannot itself be exhaustively understood. Since God is the ground of knowledge, and since we can never know things the way God knows them, our knowledge must be analogical: "The fact that man’s knowledge must always remain analogical is applicable to his knowledge of God as well as to his knowledge of the universe. God will never be exhaustively understood in his essence by man. If he were, he would no longer be God. In that case there would be no solution for the problem of knowledge"(Van Til).
From this discussion it follows that the Augustinian doctrine of the Trinity could not be a development of but had to be a reversal of the Platonic theory of knowledge. Augustine’s doctrine of the Trinity is the very axle upon which his entire theory of knowledge turns. One who embraces the doctrine of the Trinity holds that human knowledge is analogical. One who does not embrace the doctrine of the Trinity holds that human knowledge is original. This is true in the case of Plato in spite of his constant emphasis that all knowledge depends upon the soul’s relation to the world of Ideas. We have already noted that according to Plato the plurality of the sense world is ultimate, and that therefore the human mind is ultimate. Such a mind could not be satisfied with analogical knowledge. It might recognize a certain superiority in the divine mind, but it could never recognize an absolute originality in the divine mind(Van Til).
Van Til's analogical reasoning is likewise based upon the self-consciousness of the Triune God:
"Protestant epistemology as a whole may be said to have certain characteristics that distinguish it from Roman Catholic epistemology. These characteristics can all be gathered about the two heads that we have mentioned from time to time, namely, the complete self-consciousness of God and the consequent analogical reasoning on the part of man"(Van Til).
The Triune God is Himself incomprehensible to man in His Triunity. Since man cannot understand God's Triunity, yet God does, it follows that God knows Himself in a way fundamentally different from the way man knows Him. Since God likewise understands the relation of all knowledge of finite things to His own incomprehensible person, it likewise follows that man's knowledge of the relation of finite things to God differs radically from God's understanding of such, since the very ground which makes this relation comprehensible to God is itself incomprehensible to man.
The essential elements of Van Til's analogical knowledge (and its necessary corollary, his theory of the analogical predication of religious language) seems to flow from the following particulars:
1) Human knowledge is necessarily derivative of God's mind, from whom it originates.
2) The reason that this entails analogical knowledge is because the God from whom this knowledge originates is Triune.
3) This Triunity constitutes the solution to the problem of how to relate the unified ground of knowledge to the plurality of experience.
4) This solution is incomprehensible to man and can be known only to God.
5) Since God's being which constitutes the solution to the aformentioned problem is itself incomprehensible to man, it follows that God's understanding of the solution to this problem, which is the ground of all knowledge, entails that knowledge itself (for man) must be analogical, because man cannot understand the relation of knowledge to its metaphysical ground the way God understands it.
Van Til's epistemology can be summed up thus: God's Triunity constitutes the precondition of the possibility of knowledge on the ground that it resolves the problem of relating unity to diversity, yet this solution is itself known only to God and is incomprehensible to man. Therefore, Christians can have knowledge because they know that such a solution exists, but they themselves cannot understand the solution. Since God (and God alone) understands the solution to this problem because He understands His nature, only God can understand how all knowledge relates to His Triune nature, and God therefore possesses all knowledge in a way that is qualitatively distinct from man's knowledge by virtue of the latter's inability to understand how his own knowledge relates to the precondition of the possibility of knowledge whose essence is the solution to the problem of how to relate unity to diversity which resides in God's Triune nature.
It is Van Til's religious metaphysics which so sharply distinguish his own version of presuppositionalism with the presuppositionalism of Gordon Clark:
The discussion concerns the inferences Dr. Van Til draws from his theory of incomprehensibility as applied to the doctrine of the Trinity. In a Complaint against the Presbyterian of Philadelphia, signed by several of Westminster's faculty, Van Til expounds his view. The Complaint is a rather long document of fifteen pages, three columns each. Because of its length, because of its multiple signatories, and because it is a judicial complaint, one can be sure that it accurately states Van Til's position. But because of the length only a short summary can be given here.
On page two in column three the Complaint contends that "The doctrine of the incomprehensibility of God is not a mere qualification of his knowability; it is not the doctrine that God can be known only if he makes himself known....It is rather that God because of his very nature must remain incomprehensible to man." Thus at the very beginning the document lays down the principle that incomprehensibility means incomprehensibility. However, there soon comes a negative statement. "Because God is God...the divine knowledge and the knowledge possible to man may never be conceived of merely in quantitative terms, as a difference of degree rather than a difference in kind." I do not know how many "degrees" there are to the knowledge that "David was king of Israel," or that "two plus two is four," but at any rate God has a different "kind" of knowledge, so they say. One expects the Complaint to define what "kind of knowledge that is, for unless the "kind" can be known, teh difference in kind cannot be defended. If this "kind" is not explained, how could it be that "its meaning does not remain uncertain because of its unfirom significance in the history of Christian thought"?(p. 4, col. 2). But we have seen that such uniform significance is not to be found in the history of Christian thought(Clark, p. 84).
Thus, Clark has a problem with the Van Tillian notion that the Triune God is incomprehensible. Since Clark rejects the notion that the Triune God is incomprehensible, it follows that univocal knowledge (as opposed to Van Til's analogical knowledge) is unproblematic for him, because although Van Til, like Clark, holds that the Triune God is the ground and precondition for all knowledge, and that all knowledge is ultimately revelation from this God, Van Til believes that God's Triunity is incomprehensible, and that therefore the relation which all knowledge bears to this ground is itself incomprehensible.
Van Til, Cornelius. "A Survey of Christian Epistemology." Presbyterian And Reformed Publishing Co., 1969.
Clark, Gordon. "The Trinity." The Trinity Foundation, 1985.