Does ‘Ought’ Imply ‘Can’? And Did Kant Think It Does?

Abstract

The aim of this article is twofold. First, it is argued that while the principle of 'ought implies can' is certainly plausible in some form, it is tempting to misconstrue it, and that this has happened in the way it has been taken up in some of the current literature. Second, Kant's understanding of the principle is considered. Here it is argued that these problematic conceptions put the principle to work in a way that Kant does not, so that there is an important divergence here which can easily be overlooked.

Does ought imply can?

“…According to a distinguished philosophical tradition that dates back at least to Kant, obligations are in force only when the persons holding them are able to fulfil them [ 6 ] (although the depth of Kant’s commitment to the principle is debated [ 7 ]). This idea, which has been accepted by most moral philosophers, albeit in a number of different prescriptive and descriptive guises [ 8 – 10 ], is now widely known as the principle that “Ought Implies Can” (henceforth, “OIC principle”).…”

‘Ought implies Can’ and the law

“…Even when it was considered dogma, it was often invoked, although sometimes questioned-perhaps increasingly so in recent times. The principle is commonly ascribed to Kant (see Stern [2004] for the issues involved in this conception) but goes back at least to Celsus and the Justinian Digesta (D.50.:7. :85) under the formulation inpossibilium nulla obligatio.…”

Law and the Evolutionary Turn: The Relevance of Evolutionary Psychology for Legal Positivism

“…Even so, one could invoke Kant's law that “ought implies can” (Kant , 473) to argue that legal positivists cannot fully ignore the teachings of evolutionary accounts of human behaviour (see Stern ). Indeed, to study law as a normative phenomenon appears to make sense only on the assumption that legal rules have or could have some effect on the behaviour of human beings.…”