There are those, of course, who deny that they need any form of authority. They are the popular atheists and agnostics. Such men say that they must be shown by 'reason' whatever they are to accept as true. But the great thinkers among non-Christian men have taken no such position. They know that they cannot cover the whole area of reality with their knowledge.
Cornelius Van TilTo admit one's own presuppositions and to point out the presuppositions of others is therefore to maintain that all reasoning is, in the nature of the case, circular reasoning. The starting-point, the method, and the conclusion are always involved in one another.
Cornelius Van TilThe only proof for the existence of God is that without God you couldn't prove anything.
Cornelius Van Til