In epistemology, the regress argument is the argument that any proposition requires a justification. However, any justification itself requires support. This means that any proposition whatsoever can be endlessly (infinitely) questioned, resulting in infinite regress. It is a problem in epistemology and in any general situation where a statement has to be justified.[1][2][3]
The argument is also known as diallelus[4] (Latin) or diallelon, from Greek di' allelon "through or by means of one another" and as the epistemic regress problem. It is an element of the Münchhausen trilemma.[5]