Thus it happens that fashion is concerned, not merely with clothing, but also with an abundance of customary details of environment. The arrangement and furnishing of rooms, artistic objects, bodily exercises, social intercourse, sports, etc., are subject to the caprices of fashion. On this extended idea of fashion is based Fr. Th. Vischer’s definition: “Fashion is a general term to denote a complex of temporary current forms of civilization.” The =theory= of fashion has been elaborated especially by Sombart[129] and Simmel.[130] In the work of W. Fred,[131] also, we find some thoughtful observations. According to Simmel, fashion fulfils a double task. On the one hand, it is the imitation of a given example, and thus satisfies the need for social dependence; it leads the individual along the path on which all are going. But, on the other hand, it satisfies also the need for difference, the tendency to differentiation, to variation, to self-assertion. This fashion effects by means of frequent changes, and by the fact that first of all it is always a class fashion. The fashions of the upper classes are distinguished from those of the lower classes, and are instantly abandoned when the lower classes adopt them. Thus, =according to Simmel’s definition, fashion is nothing else than a peculiar form among many forms of life, by means of which the tendency towards social equalization is connected with the tendency towards individual differentiation and variation to constitute a unitary activity=. In Paris, the centre of fashion, the associated work of these two tendencies may be studied most accurately and purely. We can there observe how at first always a portion only of society adopts the fashion, whilst the commonalty are still only on the way towards its adoption. If the fashion has become entirely general, if it is followed without exception, it is already over, it is no longer “fashionable,” because this class difference has ceased to exist. “By means of this interplay--between its tendency to general diffusion on the one hand, and, on the other, the annihilation of its significance which this very diffusion brings about--fashion exercises the peculiar charm of the border-line, the charm of simultaneous beginning and ending, the charm of that which is at the same time new and obsolete” (Simmel). In connexion with this fact we find that from the earliest times the “=demi-monde=” has always given the impulse to new fashions. Owing to the peculiarly uncertain position occupied by this class, everything conventional, everything long in use, is detested by its members; only newness and change are agreeable.