Abstract

Underdetermination is a relation between evidence and theory. More accurately, it is a relation between the propositions that express the (relevant) evidence and the propositions that constitute the theory. Evidence is said to underdetermine theory. This may mean two things. First, the evidence cannot prove the truth of the theory. Second, the evidence cannot render the theory probable. Let’s call the first deductive underdetermination, and the second inductive (or ampliative) underdetermination. Both kinds of claim are supposed to have a certain epistemic implication, viz., that belief in theory is never warranted by the evidence. This is the underdetermination thesis