While fashion is thought of usually in relation to clothing, it is important to realize that it covers a much wider domain. It is to be found in manners, the arts, literature, and philosophy, and may even reach into certain areas of science. In fact, it may operate in any field of group life, apart from the technological and utilitarian area and the area of the sacred．Its operation requires a class society, for in its essential character it docs not occur either in a homogeneous society like a primitive group, or in a caste society. Fashion behaves as a movement, and on this basis it is different from custom which, by comparison, is static．This is due to the fact that fashion is based fundamentally on differentiation and emulation. In a class society, the upper classes or so-called social elite are not able to differentiate themselves by fixed symbols or badges. Hence the more external features of their life and behavior. are likely to be imitated by classes immediately below them, who, in turn, are imitated by groups immediately below them in the social structure. This process gives to fashion a vertical descent. However, the elite class finds that it is no longer distinguishable, by reason of the imitation made by others, and hence is led to adopt new differentiating criteria, only to displace these as they in turn are imitated．It is primarily this feature that makes fashion into a movement and which has led one writer to remark that a fashion, once launched, moves to its doom. As a movement, fashion show little resemblance to any of the other movements which we have considered．While it occurs spontaneously and moves along in a characteristic cycle, it in volves little in the way of crowd behavior. and it is not dependent upon the discussion process and the resulting public opinion. It does not depend upon the mechanisms of which we have spoken. The participants are not recruited through agitation. No morale is built up among them. Nor does the fashion movement have, or required, an ideology. Further, since it does not have a leader- ship imparting conscious direction to the movement, it does not build up a set of tactics. People take part in the fashion movement voluntarily and in response to the interesting and powerful kind of control which fashion imposes on them. It is known from the first paragraph that______