Apologetical disputes between believers and unbelievers depend upon, include by reference, and arise out of conflicting epistemologies. Conflicts over the theory of knowledge in turn incorporate, function within, and must address differing world-and-life views (with divergent concepts of man as a knower), if they would be resolved. The bold defense of the faith offered by Van Til’s presuppositionalism is that the unbeliever’s worldview fails to provide an adequate or workable theory of knowledge in terms of which the non-Christian can intellectually challenge the truth of Christianity. His presuppositions preclude the unbeliever from making claims to know anything intelligible or meaningful.
The Christian worldview begins with the personal, self-sufficient, sovereign, and triune God, who created all things from nothing and made man to be His image. God knows all things, and directs all events by His wise, providential plan. Thus, all objects, properties, minds, events, general laws, and moral prescriptions are determined, controlled, and related to each other by the mind of the Lord. Whatever the Lord says is utterly truthful and unfailing in its purposes, and that includes every passage of the Old and New Testaments. Human behavior and reasoning have become immoral and futile, due to self-centered rebellion against God. Man is biased against and hostile to the Lord and His revelation, wishing to be his own ultimate authority (autonomous). He needs the redemptive work of God’s incarnate Son (as a prophet, priest, and king) and the regenerating work of God’s Holy Spirit to be saved from intellectual foolishness, moral guilt, and eternal damnation. Given this overall “picture” of God, the world, man, value, history, and salvation—the basic biblical world-and-life view—the Christian can give an account of the objectivity of truth; the mind’s correspondence to objects and other minds; the possibility of knowledge; the rational and empirical procedures by which we learn, test, and justify propositions; the possibility of our finite minds knowing universal, absolute, and prescriptive concepts and laws; the human tendency toward disagreement, prejudice, and irrationality, etc.