Does ‘ought not’ imply ‘can’?

Daniel B Cohen (Charles Sturt University)

Considerable attention has been given to the Kantian principle  ‘ought implies can’ (OIC). However, far less attention has been given to a related principle, ‘ought not implies can’ (ONIC). In this paper, we outline the case for ONIC. We start by considering four familiar arguments which have been offered for OIC. For each of these arguments we formulate a corresponding ‘mirror’ argument for ONIC and, in most cases, we argue that the mirror argument is at least as plausible as the original -- if the original argument for OIC is sound, then so too is the mirror argument for ONIC. This shows that many of the considerations which have been offered in support of OIC also support ONIC. We also consider two arguments for ONIC which employ OIC as a premise.