The Presuppositionalism of Calvin

The apprehension of truth is not heart-condition-neutral. The common grace of reason is insufficient in assisting man in going from the particulars to the universals. Truth is not a banquet table from which everyone can feast. The best that the unregenerate can partake of is the measly morsel of Deism. To be able to think, and think truly, regeneration is the prerequisite.

"Christ, therefore, replies that sound judgment flows from fear and reverence for God; so that, if their minds be well disposed to the fear of God, they will easily perceive if what he preaches be true or not. He likewise administers to them, by it, an indirect reproof; for how comes it that they cannot distinguish between falsehood and truth, but because they want the principal requisite to sound understanding, namely, piety, and the earnest desire to obey God?" (John Calvin, Commentary on John — Volume I (Grand Rapids, MI: Christian Classic Ethereal Library), John 7:17).