Clive Bell (1881-1964) was a British art critic and philosopher of art who defended abstract art. Bell's aesthetic theory was focused on aesthetic experience. He claimed (in his book Art, 1914) that there is a certain uniquely aesthetic emotion, and that aesthetic qualites are the qualities in an object that evoke this emotion. In the visual arts, what arouses this emotion is certain "forms and relations of forms" (including line and color), which Bell called "significant form". Aesthetic response to significant form is not to be identified, according to Bell, with other emotional responses. For example, a photograph of a loved one might evoke fond memories and feelings of love; the statue of the planting of the flag at Iwo Jima might arouse feelings of patriotism; the Vietnam War Memorial might evoke feelings of grief or lament (my examples). While these are all perfectly appropriate responses, they are not aesthetic responses. Rather the aesthetic response is a response to the forms and relations of forms themselves, regardless of what other meanings, associations or uses they may have. It is a strong emotion, often a kind of ecstasy, akin to the ecstasy felt in religious contemplation. The emotion, and the kinds of significant form that evoke it, are the same for cave art, Polynesian carvings, a Vermeer painting or a Cezanne.
Bell's theory has obvious philosophical connections to the aesthetics of Immanuel Kant, who also streesed the detachment of aesthetic appreciation from other sorts of interest we might have in an object. His views also have close affinities with the ethical intuitionism of his British contemporary, the philosopher G.E. Moore. Moore is famous for claiming, in Principia Ethica (Cambridge University Press, 1903) that goodness is a property that things have in themselves, and that we know things to be good by a kind of intuition: one simply contemplates an object or a state of affairs and recognizes immediately and directly that it is good, in much the same way that one recognizes that it is red. Bell agreed with Moore, and considered aesthetic value to be one of these intuited forms of goodness.
It is easy to see how Bell's aesthetic would enable him to defend abstract art. For him, the aesthetic value of a painting or sculpture has absolutely nothing to do with its success as a representation of something else. Vasari to the contrary notwithstanding, if the Renaissance masters are great, it is not because they were so good at imitating nature, but because of the formal properties of their work. Judged by this new standard, Bell found many highly praised masters from the Renaissance through Impressionism to be deficient. (That was his judgment in Art; in his later writings he showed more appreciation for these painters.)
Like the aesthetics of Kant, that of Bell has a certain initial appeal, and no doubt represents an insight. In discussing a work of art, does it not often seem appropriate to draw the conversation back to the aesthetic quality of the work, in distinction from its skillful technique, its romantic associations, or what have you? Nevertheless Bell's theory has not withstood criticism well. Among the difficulties it faces are its apparent circularity, a problem it shares with Moore's intuitionist ethics. The conceptual circle of aesthetic emotion, aesthetic quality, and significant form is so small that in the end, one cannot give reasons why a work is good. For a theory which means to claim that some works objectively have aesthetic value and others do not, this is a set-up for the tyranny of unjustified judgements by influential critics.
A second problem of Bell's view is its sharp separation between aesthetic and other emotions. Some writers have questioned whether there is any such thing as the "aesthetic emotion". Even if there is such an emotion, it seems obvious that the power and value of many works is tied into their communication of meaning, and that their formal properties are only part of the vocabulary they use to communicate this meaning. Bell's theory seems to leave symbolism out of account, and no view that does that can be an adequate aesthetic theory.