The non-Christian holds that pure chance and absolute fate are equally ultimate and mutually correlative limiting concepts or heuristic principles which man uses to explain the fact that we have learned much about the world, that there is order in the world, a uniformity, while there is also continual change and development. But the non-Christian’s “explanation” is no explanation at all. To say “it just happens” as an explanation of an event is really to say, “There is no explanation that I know of.”
The Calvinist, therefore, using his point of contact, observes to the non-Christian that if the world were not what Scripture says it is, if the natural man’s knowledge were not actually rooted in the creation and providence of God, then there could be no knowledge whatsoever. The Christian claims that non-Christians have made and now make many discoveries about the true state of affairs of the universe simply because the universe is what Christ says it is. The unbelieving scientist borrows or steals the Christian principles of creation and providence every time he says that an “explanation” is possible, for he knows he cannot account for “explanation” on his own. As the image-bearer of God, operating in a universe controlled by God, the unbeliever contributes indirectly and adventitiously to the development of human knowledge and culture.
… the Christian offers the self-attesting Christ to the world as the only foundation upon which a man must stand in order to give any “reasons” for anything at all. The whole notion of “giving reasons” is completely destroyed by any ontology other than the Christian one. The Christian claims that only after accepting the biblical scheme of things will any man be able to understand and account for his own rationality.
– Cornelius Van Til, My Credo (Jerusalem and Athens) p.17-18