Totalitarianism specializes in the dissolution of fortitude, whether by the extremes of physical torture (Bettelheim 1943) or by the psychological degradation of “thought reform” or “brainwashing” (Lifton 1956; Schein 1956). These practices are repellent, but their effects are not unexpected. Aristotle (1984: 1115b7—9) acknowledged that some things exceed human endurance, and Russell (1945: 267), with another 2,000-odd years of history to consider, remarked that the will withstands the tyrant only so long as the tyrant is unscientific. Situationism teaches something more surprising and, in a sense, more disturbing. The unsettling observation doesn't concern behavior in extremis, but behavior in situations that are rather less than extreme; the problem is not that substantial situational factors have substantial effects on what people do, but that seemingly insubstantial situational factors have substantial effects on what people do. The disproportionate impact of these “insubstantial” situational factors presses charges of empirical inadequacy against characterological moral psychology: If dispositional structures were typically so robust as familiar conceptions of character and personality lead one to believe, insubstantial factors would not so frequently have such impressive effects. In the present chapter, I'll document the evidence for this contention.