Beyond “ought Implies Feasible”

Abstract

What kinds of feasibility restrictions should be taken into account in practically relevant political philosophy? David Estlund argues that “ought” does not imply “can will,” and, hence, that we should be very cautious regarding the inclusion of motivational restrictions in political philosophy. As Nicholas Southwood and David Wiens point out, however, Estlund’s position clashes with the requirement that “ought” implies “feasible.” The present article argues that even though we must accept that “ought” implies “feasible,” this does not settle the question regarding the adequate set of feasibility restrictions to be included in applied normative thinking. Instead, we need to distinguish different kinds of normative theory that require different sets of feasibility restrictions. For this, the article provides a taxonomy of feasibility restrictions and a preliminary discussion of the adequate set of feasibility restrictions for different kinds of normative theory.