Well, his argument is that the imputation of responsibility is an effective tool that the powerful use to control and punish the powerless. As andie notes, N's "deep" psychology calls into question our common sense notions that there is some unitary self/subject that is "responsible" for actions. For N, each of us is a tangle of impulses, instincts, habits, desires; upon this complexity we impose the fiction of the unified agent. I regret that Fred wasn't around to skewer the naive psychology of modern economics.
Miles