  A broader question arises here. By concentrating on purported deficits of rationality of Africans in particular, and blacks in general, as opposed to examining its causes (say, slavery and race discrimination), isn't the analysis misplaced? After all, if the causes of diminished cognitive resources are political and historical, then any proposed remedy would presumably have to offset (if not remove) those causes. One could go even further (as Crummell easily could) and argue that if cognitive resources are diminished due to morally pernicious causes, then moral progress will be stymied unless and until a just accounting of those causes has been made, and remedies are carried out.