In an earlier post I discussed my approach to solipsism. In brief, my approach is not to attempt to prove that solipsism is false, but to show that it is not the skeptical philosophy it claims to be. For to doubt the reality of the external world is at the same time to affirm that my own mind is responsible for everything that common sense attributes to the external world. Solipsism can only be true if my own mind is responsible for the discoveries of Newton, Maxwell and Einstein, the plays of Sophocles and Shakespeare, the novels of Dostoyevsky, and the art of Rembrandt and Michelangelo.
Now if instead of claiming that solipsism is doubt of the external world, the solipsist claimed that his own mind is in fact responsible for all the achievements of the individuals listed above, it would be immediately recognized that the position is not one of skepticism but of colossal intellectual arrogance. Yet the standard presentation of solipsism and my reformulation of it are logically equivalent.
I think a similar analysis holds with the philosophy of Kant. Kant's "Copernican revolution in philosophy", we will recall, holds that the forms the ancient philosophers found in nature are really constructions the human cognitive apparatus places on raw experience. So we can't know the true nature of things in themselves, but only those things as they appear filtered through human cognition.
Like solipsism, however, the Kantian Copernican revolution can be reformulated as a claim that the forms we find in experience are generated in the human mind. The beauty of the Grand Canyon, or the singing of a lark, the majesty of the lion - from the Kantian perspective we must affirm that these are creations of the human mind, not things that come from a reality greater than us. So just as the solipsist must believe he is a mathematician at least as great as Newton, the Kantian must believe he is a creator greater than whatever is responsible for nature; God perhaps. So Kantianism isn't really the skeptical philosophy it claims to be. It is rather a colossal affirmation of the self against anything greater than the self.
