The trouble is that we have all been such an observer. All categories of race are discretionary ones developed out of custom, habit, and, if not convenience, ignorance. It is true that large groups of people -- entire societies -- have been successful in establishing categories of identity that correlate with loosely defined sets of physical features. But their success depended almost wholly on the accident that we are impatient and we see faces as succinct reports of an individual's identity. We do not see the individual in her entirety.