One might suppose that within a few years after the publication of the Philosophical Investigations, the direction of philosophical work would have sharply altered. Philosophers would no longer be searching for the universal, the essential. But if one supposed this, one would be wrong. Books containing theories of art, of thinking, of belief, of ethics, of action, of knowledge, of language, continue to abound. Much of this writing, of course, has gone down without leaving a ripple; but some of it has made waves.