Aesthetics in its inner nature fundamentally challenges assumptions found in philosophy: e.g. foundationalism, dogmatic commitment to clear and distinct ideas, acceptance of various dualisms, and the view that philosophical methods must be modeled after those of science. Aesthetics is a tensional moment within the organic whole of philosophy. If philosophy is to regain harmony it must extrude aesthetics, destroy it, or transform it -- or else aesthetics must transform philosophy.
Aesthetics challenges conventional notions of rationality, reality, truth, and ethics. This is sometimes not apparent because much of contemporary aesthetic theory is actually a philosophical defense against the spirit of aesthetics, an aspect of the ancient battle between philosophy and the arts once referred to by Plato. Usually aesthetics is seen as at the periphery of philosophy. This is largely because of its close association with the arts as well as with sensuous properties which have been traditionally associated by philosophers with the frivolous and superficial. On this view it is thought that the core subdisciplines of philosophy are metaphysics, epistemology, ethics/political philosophy, and logic, with philosophy of mind and philosophy of language running in second place, or perhaps moving to first place. Aesthetics is indeed a kind of step-child of philosophy.
The deepest challenge that both art and, potentially, the philosophy of art, poses for philosophy all of one piece, machine-like, logical in the manner of propositional logic. All (or almost all) philosophers are rationalists in the end. Certainly I am. But there are different approaches to rationalism. One approach, much maligned traditionally, is that there is an irrational element at the heart of rationality itself. This irrational element is most easily found in the creative process whether that be in art, business, science or philosophy itself. Creativity requires violating boundaries, overcoming categories, seeing things in radically new ways. The inceptive moment in the creative process is fundamentally irrational. Knowledge is impossible without this moment since knowledge is based on creative thinking every bit as much as on careful collection of evidence. Plato was fascinated with this element and occasionally played with it, as for example in his Ion, his Phaedrus, and his Symposium, although he usually rejected it in the end. For him, the irrational element is understood as the madness of love, or at least one kind of madness of love. It can also be found, more subtly, in his doctrine of recollection.
None of this is to claim that the irrational cannot lead to suffering. The negative capacity of the irrational is proved every day. And yet there is a positive irrational. And the positive irrational is importantly valuable. It is possible (plausible?) that embracing the positive irrational (for example in such a way as to affirm rationalism in the end) is necessary to solve our problems today.
That is, only through a synthesis of the irrational and the rational where the end result is ultimately rational can we really work in such a way as to handle the repressed emotions that can wreck havoc in our lives. Freud, despite all of his failings, recognized the fundamental importance of the positive irrational.
Logicist/scientistic understanding of rationalism ultimately ends in failure because the possibility of creative thinking is lost.
One strategy that is useful in aesthetics can help in understanding the role of the positive irrational. In the aesthetics of nature it is commonly thought that the appropriate way to appreciate nature is either through an art-like approach or by way of scientific understanding. Some philosophers are beginning to recognize that a pluralist approach is best, particularly if it is fully integrated. I and others have proposed the ideal of John Muir who synthesized not only the arts-based and scientific approaches but also a transcendental or religious based approach. As an atheist, I reject a literal existent God, and yet the idea of God has sometimes been used to express something quite real: the positive irrational element in complete fulfilled experience, in this case, of nature. Nietzsche saw this in his notion of the Apollonian Dionysian duality and particularly in his idea of the Dionysian.
It is an interesting fact that the term "irrationalism" does not appear as a heading in the Stanford Encyclopedia of Philosophy or even in the index in the Encyclopedia of Aesthetics, the two main encyclopedias I use, and yet it is present as an entry both in the Encyclopedia Britannica here and in the New World Encyclopedia. The Encyclopedia Britannica says it was a 19th and early twentieth century movement that "stressed the dimensions of instinct, feeling, and will as over and against reason." How about a 21st century movement that stresses this dimension as forming a necessary basis for reason? It is not irrationalism against rationalism, but a positive irrationalism within rationalism at its best. That essay turns to the early Greek philosopher as often having a "strain" of irrationalism. This would be true of Heraclitus but also even for Plato as mentioned above. The Sophists, the Skeptics and the Cynics all also had strains of irrationalism. The term is often associated with faith and intuition. Other names connected with irrationalism include Pascal, Kierkegaard, Nietzsche and the existentialists. The essay associates it with literary romanticism. The anonymous writer talks about irrationalism as coming after the Age of Reason and as being in some way associated with Darwin and Freud (neither one of whom would have thought of himself as irrationalist, and both of whom might be said to have suppressed the irrationalist side of their thinking). If experience is based on biology and the unconscious then it is not based ultimately on reason: reason itself is not based ultimately on reason. The sentence "Pragmatism, existentialism, and vitalism (or “life philosophy”) all arose as expressions of this expanded view of human life and thought" implies that there is a strain of irrationalism in all of these: and I think there is. My own irrationalism is in the mode of pragmatism with a strong emphasis on positive irrationalism which must, to be used successfully, be brought up into the larger rationalist project. As the author observes, Peirce and James arguing that ideas need to be assessed on practical rather than strictly logical grounds, has an irrationalist side. I hope to have more to say about irrationalism and its relationship to aesthetics in the coming months.