Paul Guyer is probably our leading historian in Western philosophical aesthetics. He had just come out with his humungous History of Modern Aesthetics in three volumes with 1700 pages costing a minimum of $300. All I can say is that I hope my library buys a copy. Easier to read quickly is his article "Monism and Pluralism in the History of Aesthetics" Journal of Aesthetics and Art Criticism 71:2 (Spring 2013). This is a very illuminating overview of his project, including the moral he has drawn from writing his history. His basic point is that modern philosophy saw three main functions for art: cognition, free play of the imagination, and expression of emotion, and that although many in the history of aesthetics have argued that art should only serve one of these functions (monism), Guyer favors the idea, expressed from time to time, that art should (or can?) serve all three (pluralism.)
He begins by observing that the person who invented the term "aesthetics" Alexander Baumgarten in his Philosophical Meditations on some Matters pertaining to Poetry of 1735 defined "poetics" as the "science of the perfect presentation of sensory representations." He later (in his Aesthetica, 1750) defined aesthetics along similar lines and said that it was the "science of sensory cognition." I have always been puzzled as to the relationship between these definitions and aesthetics as we practice it today. I understand that what we translate as "science" can mean "study." The puzzling part is "sensory cognition." There could, for example, be cognition that is happens primarily through the senses (no reasoning involved) but without any art. Presumably what is being suggested is that the arts somehow present us with, evokes or manifests sensory knowledge. Also, is the claim that works of art perfectly present sensory representations? Is a poem supposed to be a sensory representation? Is it being said that perfect representation of the subject matter by way of the senses is the ideal?
Baumgarten's further explication of aesthetics (quoted by Guyer) as "the theory of the liberal arts, the doctrine of inferior cognition, the art of thinking beautifully, the art of the analogue of reason" does not help much. It seems like a mish-mash of different ideas. The theory of the liberal arts might just involve debates over what the liberal arts might be. That the arts provide a form of cognition inferior to, let us assume, the sciences, is a sad thought, if true. If there is an art of thinking beautifully it might happen in art, religion, science, philosophy, or everyday life. So why just associate it with the liberal arts? One can think beautiful thoughts about all sorts of things, although I am not clear what a beautiful thought is. And what exactly is the analogue of reason? As usual, I find myself wishing I had a good English translation of the entire text, or that I could read it in German. Guyer himself does not try to explicate this, but simply uses the quote to infer that Baumgarten was not a cognitivist but some sort of pluralist. The two other approaches (apart from the cognitivist approach) are described by Guyer as "the idea that the pleasure of such experience comes from the enjoyment of the emotional impact of art, and the idea that the pleasure of such experience comes from the free play of our mental powers triggered by works of art or nature", a free play that cannot be reduced to cognition. Wise aestheticians, on his view, recognize that "works of art and nature could please us in all these ways." (134) Heroes of the pluralist approach are Lord Kames in the 18th century, Wilhelm Dilthey and George Santayana in the 19th, and Monroe Beardsley and Richard Wollheim in the 20th. I was surprised the John Dewey was not included although such lesser figures as DeWitt Parker, T.M. Greene and D. W. Gotshalk are.
An interesting feature of Guyer's approach is that he is able to lump very diverse figures in aesthetics under what he calls cognitivism. The object of aesthetic cognition for Wolff is perfection, for Hegel spirit, for Schopenhauer the Platonic Ideas, for Heidegger "Being," and for Lukacs capitalism. Another group includes those who focus on the emotional impact of art, beginning with De Bos in 1719. Another interesting feature of the article is that although aestheticians will naturally associate the free play of imagination with Kant, Guyer traces the idea back to Addison's "The Pleasures of the Imagination" (1712) Guyer associates Addison's idea of Beauty. He quotes from Addison "a spacious Horison is the Image of Liberty, where the Eye has room to range abroad, to expatiate at large on the Immensity of its Views, and to lose it self amidst the Variety of Objects that offer themselves to Observations." The quote from Addison is fascinating, the eye anthropomorphized here as a kind of tourist who freely ranges, expatiates, loses himself and makes observations.
Interested in learning more? See my book: Thomas Leddy The Extraordinary in the Ordinary: The Aesthetics of Everyday Life. Broadview Press, 2012. Available at Amazon in paperback, and an electronic version at google where you can also find most of the first 47 pages including the table of contents. You can also buy it fro Broadview.