Presuppositions are the foundational assumptions, basic commitments, or heartfelt convictions which determine how a person interprets reality.  In other words, a presupposition provides the metaphysical basis by which a person claims to understand sensation, experience, and reason.  Not all presuppositions are true, and thus those who base their lives on false presuppositions, live a life of error, no matter how consistent they are with respect to those presuppositions.  Presuppositionalism is a
philosophical approach which states that a person’s presuppositions determine his ‘Weltanschauung’ (world view).