The concept is applied in a variety of disciplines, with both
the nature of the evidence or justification and the criteria for
sufficiency being area-dependent. In the area of oral and
written communication such as conversation, dialog, rhetoric,
etc., a proof is a persuasive perlocutionary speech act, which
demonstrates the truth of a proposition. In any area of
mathematics defined by its assumptions or axioms, a proof is an
argument establishing a theorem of that area via accepted rules
of inference starting from those axioms and other previously
established theorems. The subject of logic, in particular proof
theory, formalizes and studies the notion of formal proof. In
the areas of epistemology and theology, the notion of
justification plays approximately the role of proof, while in
jurisprudence the corresponding term is evidence, with burden of
proof as a concept common to both philosophy and law. In most
disciplines, evidence is required to prove something. Evidence
is drawn from experience of the world