  The term “aesthetics” as it first emerged in modern philosophy (in A. G. Baumgarten’s 1750 Aesthetica) encompassed the theory of perception, the theory of beauty and the theory of art. This remained true of all classical philosophical aesthetics in the late 18th and 19th centuries. In this brand of aesthetics, the aesthetic moment is but one aspect of the general theory of how humans perceive, know, and act in the world; the theories of beauty and of artistic practice depend on the theories of perception, knowledge and judgement, and those in turn are premised upon more fundamental considerations regarding the nature of reality and our relationship to it. By contrast with the specialised aesthetic theories developed in the last few decades, existentialist aesthetics is a continuation of this grand tradition. Existentialist aesthetics is intimately connected to certain metaphysical views, and it owes its richness and consistency to the fact that it is part of a complex and coherent philosophical system. Therefore we should begin by delineating the most salient features of this metaphysical outlook.