We would, it seems, be justified in imprisoning or institutionalizing them for such an act to prevent them from harming others. But the other justifications for punishment – retribution, rehabilitation, and deterrence – seem not to apply very well. By definition, a prison sentence couldn’t deter an individual from doing something he can’t stop himself from doing and rehabilitation could not change an immutable characteristic. Retribution would be even more problematically incoherent. We believe that a man must be able to do what he ought to do; we could not condemn a man for doing something that we believe he cannot choose not to do.