Abstract

The problem of unconceived alternatives states that, since scientists have recurrently failed to conceive relevant theoretical alternatives for some domains of science, current scientists are probably also failing to do so. Therefore, there may be theories which still exceed the grasp of scientists’ imagination, and one should not endorse a realist stance towards current science. In this paper, I raise a conceptual worry for the formulation of this problem: what does it mean to say that scientists failed to conceive a relevant theory? What aggravates the problem is that no simple notion of relevance makes the New Induction as strong as it initially seems. I consider the three more obvious interpretations of relevance: relevance as objective probability; relevance as epistemic probability assessed by current scientists; and relevance as epistemic probability assessed by past scientists. I argue that assuming any of these three notions implies difficulties for the New Induction, hence their proponents shouldn’t take the notion of relevance for granted. A more precise definition of relevance is essential to understand what are the difficulties surrounding the problem of unconceived alternatives as an epistemic worry. Until now, such notion is missing. KeyWords: Scientific realism, unconceived alternatives, Kyle Stanford, New Induction, Pessimistic Induction.