In the Tractatus, Wittgenstein claimed that the problems of philosophy arise when "the logic of our language is misunderstood." He also claimed to have given "on all essential points, the final solution of the problems." Wittgenstein thought he had provided this solution by analyzing the relation of language to the world, showing the boundaries of what can intelligibly be said or thought. Central to his analysis is a theory of meaning, usually referred to as the picture theory. The picture theory states that simple objects exist, out of which complex ones are constructed. The relations of these objects to one another are represented, or pictured, in language, and only what can be so pictured can be stated intelligibly. The nature of the picturing relationship cannot be stated; because it is not a fact or an object, it can only be shown. Even though the relation cannot be articulated, it is possible to see it, and it must hold if language is to represent the way the world is. For Wittgenstein, therefore, the traditional problems of philosophy are not solved, but rather dissolved, because they arise from a failure to understand the picturing relations; consequently, the problems ask for answers to questions that are nonsensical. Once the nature of meaning is grasped, the problems cease to exist.
This view of philosophy and its problems was influential from the start. His conclusions seemed to provide a method whereby many philosophical theories--notably those related to metaphysics and most of ethics--could be discarded as nonsense.
Although the Tractatus retained considerable influence in logical positivism, it was Wittgenstein himself, in his later philosophy, who eventually produced the most devastating critique of his early work. He still viewed philosophical problems as arising in some way from confusion about language, and he still saw his work as a means of dissolving these problems. In the Tractatus, however, Wittgenstein had thought of language primarily as giving and manipulating the names of given objects. In his later work he considered this inadequate, because naming can only take place in the context of a developed language, for which there already exist rules for picking out objects, properlyusing names, and properly carrying out operations. The criteria for these activities, in turn, are to be found not in logic but in the actual practice of a language-using group. Thus, while his early philosophy equates meaning with representing, or picturing, the later philosophy sees meaning in terms of doing, of participating in what he calls a "language game." Wittgenstein held that any general theory of meaning would be inadequate to dispel philosophical perplexity and that the way to escape the bewitchment of the mind by language is to examine in detail how the language in question is used in the particular language game in which it is found.
With his insights on language and meaning, Wittgenstein shed new light on a variety of problems, notably skepticism and the problem of other minds. His work, however, has been extended by other thinkers into all areas of philosophy.