Aesthetics may be defined narrowly as the theory of beauty, or more broadly as that together with the philosophy of art. The traditional interest in beauty itself broadened, in the eighteenth century, to include the sublime, and since 1950 or so the number of pure aesthetic concepts discussed in the literature has expanded even more. Traditionally, the philosophy of art concentrated on its definition, but recently this has not been the focus, with careful analyses of aspects of art largely replacing it. Philosophical aesthetics is here considered to center on these latter-day developments. Thus, after a survey of ideas about beauty and related concepts, questions about the value of aesthetic experience and the variety of aesthetic attitudes will be addressed, before turning to matters which separate art from pure aesthetics, notably the presence of intention. That will lead to a survey of some of the main definitions of art which have been proposed, together with an account of the recent "de-definition" period. The concepts of expression, representation, and the nature of art Objects will then be covered.
The eighteenth century was a surprisingly peaceful time, but this turned out to be the lull before the storm, since out of its orderly classicism there developed a wild romanticism in Art and Literature, and even revolution in politics. The aesthetic concept which came to be more appreciated in this period was associated with this, namely Sublimity, which Edmund Burke theorised about in his "A Philosophical Enquiry into the Origin of our ideas of the Sublime and Beautiful." The Sublime was connected more with pain than pure pleasure, according to Burke, since threats to self-preservation were involved, as on the high seas, and lonely moors, with the devilish humans and dramatic passions that artists and writers were about to portray. But in these circumstances, of course, it is still "delightful horror," as Burke appreciated, since one is insulated by the fictionality of the work in question from any real danger.
"Sublime" and "beautiful" are only two amongst the many terms which may be used to describe our aesthetic experiences. Clearly there are "ridiculous" and "ugly," for a start, as well. But the more discriminating will have no difficulty also finding something maybe "fine," or "lovely" rather than "awful" or "hideous," and "exquisite" or "superb" rather than "gross" or "foul." Frank Sibley wrote a notable series of articles, starting in 1959, defending a view of aesthetic concepts as a whole. He said that they were not rule- or condition-governed, but required a heightened form of perception, which one might call Taste, Sensitivity, or Judgement. His full analysis, however, contained another aspect, since he was not only concerned with the sorts of concepts mentioned above, but also with a set of others which had a rather different character. For one can describe works of art, often enough, in terms which relate primarily to the emotional and mental life of human beings. One can call them "joyful," "melancholy," "serene," "witty," "vulgar," and "humble," for instance. These are evidently not purely aesthetic terms, because of their further uses, but they are still very relevant to many aesthetic experiences.
Sibley's claim about these concepts was that there were no sufficient conditions for their application. For many concepts