Externalization of moral demands does not motivate exclusion of non-cooperators: A defense of a subjectivist moral psychology.

It is not clear how a moral demand alone can motivate an agent to exclude those who fail to act as the demand states. A more plausible hypothesis for the evolution of human moral cognition is based on seeing moral demands as subjective, but inherently conjunctive. This subjectivist-conjunctive proposal can still account for the apparent externalization of moral demands.