Aesthetics. The study of the concepts of 'beauty' and 'art'. A. attempts to give an account of the human reaction to beauty and art, to define the words, to explain how men perceive the 'beautiful' or the 'artistic', to decide whether the concepts have any other than a subjective meaning and to explain what happens when a man stands before a 'beautiful' sight or a work of 'art' — what kind of experiences he has and in what way he is able to 'experience' anything. Although the writings of Plato and Aristotle contain observations on the subject matter of a., the word was first used by the 18th-c. German philosopher A. G. Baumgarten. Some of the most prominent theoreticians in a. since the 19th с include Winckelmann, I. Kant, Lessing, J. Schiller, G. Hegel, J. G. Herder, F. Schelling, Ruskin, Baudelaire, Taine, F. Nietzsche, Crocc, Worringer and Gombrich.