Theory of justification is a part of
epistemology that attempts to understand the justification of
propositions and
beliefs. Epistemologists are concerned with various epistemic features of belief, which include the ideas of justification, warrant,
rationality, and
probability. Of these four terms, the term that has been most widely used and discussed by the early 21st century is "warrant". Loosely speaking, justification is the reason that someone (properly) holds a belief.