The art world is often daunting. It can feel esoteric and inaccessible, with the criteria for what is beautiful, popular, and expensive changing quickly according to whim. Few of us realize that what we think about art is laden with ideas from Descartes, Hobbes, Kant, Marx, Hegel, Nietzsche and so on. By and large, these men have all added to the intellectual soup of our contemporary world. We think their thoughts unthinkingly.