The idea that reason is the primary and most appropriate source of knowledge is known as rationalism. This theory holds that knowledge should be determined by reason and factual analysis rather than faith, dogma, tradition or religious teachings. It can be clearly defined as a methodology in which the criterion of truth is not sensory but intellectual and deductive. On the opposite end of the spectrum, fideism holds that faith is necessary, and that beliefs may be held without any evidence or reason and even in conflict with evidence and reason. Fideism maintains that faith is independent of reason and that faith is superior when it comes to arriving at particular truths. Danish philosopher and theologian, Søren Kierkegaard, claims that the existence of God cannot be indubitably known and that the decision to accept faith cannot be, nor needs to be, founded on logical justification.
