Cornelius Van Til was a 20th century protégé of the Dutch Reformed theologian and president of the Netherlands, Abraham Kuyper. Van Til created a school of Christian apologetics and an ethical system based on Kuyperian presuppositionalism. Although Van Til had some disagreements with Kuyper, the two systems are similar.
According to Van Til, presuppositionalism is the idea that all philosophical reasoning is ultimately circular. Every argument begins with an unprovable premise. Given a true premise, one can arrive at a valid conclusion that is equally true. The problem is that one can never be absolutely certain that the premises of an argument are true. Van Til said that scriptural presuppositions are true because the Bible is God’s Word. To Van Til, any other rationalist system was untrustworthy because it must be based on the presuppositions of human beings corrupted by the Fall of Adam.
A “true” premise implies the sufficiency of human reason. One may attempt to prove a premise through argumentation. Yet these arguments will be supported by equally unprovable premises. A true premise implies that one has either consciously or unconsciously arrived at a foregone conclusion. Circular reasoning is inescapable. Furthermore, this is always the reasoning of an imperfect mind. Therefore, only premises that come from a perfect mind, such as those originating from the inscripturated Word of God, are trustworthy and reliable.
Van Til’s system of apologetics states that the Christian ought not to use rational argument to attempt to prove the truth of God’s Word to non-believers. The Christian ought to start all argumentation with scripture as a presupposition. Van Til did not deny that there are rational arguments that prove the validity of the Word of God. On the contrary, nothing exists except proof. Yet human beings have a problem with comprehending the Word of God as truth. The problem is not philosophical in nature, but rather moral. The problem is that our understanding is clouded by original sin and therefore we have a problem with comprehending the truth.
This way of thinking cuts across the grain of modern rational thought which proposes that one must prove something in order to believe it to be true. However, Van Tillian logic has had many forerunners in the medieval and ancient world.
St. Anselm, Archbishop of Canterbury wrote, “For I seek not to understand in order that I may believe; but I believe in order that I may understand, for I believe for this reason: that unless I believe, I cannot understand.”
This is the opposite of the famous maxim, “I think therefore I am.” Rationalists such as Descartes have always wanted to “understand it” or “prove it” in order to believe it. However, Anselm’s statement is undeniably true. All truth is based on certain unprovable presuppositions. We must first have faith in order to know anything.