Ludwig Wittgenstein is probably the only philosopher in history who gave the world two distinct philosophies, and influenced two major philosophical movements besides. The philosophy of his youth was called "logical atomism," and was encapsulated in a book entitled Tractatus Logtco-Philosophtcus, a work which was heavily influenced by the new symbolic logic of Gottlob Frege and Bertrand Russell. Indeed, this first philosophy may be characterized as the philosophy of symbolic logic. His later philosophy, embodied in the posthumously published Philosophical Investigations, which repudiated important concepts of the philosophy of his youth, may be characterized as ordinary language philosophy. What the two philosophies had in common was their being language-based. The first one was based on the formal language of logic and sought to overcome the limitations of ordinary language, which Wittgenstein then believed to be the source of philosophical confusions. In the second philosophy, Wittgenstein became convinced of the inadequacies of formal language analysis and came to the conclusion that the analysis based on ordinary language is adequate for the purpose of ridding philosophy of its puzzles. In both cases, Wittgenstein claimed that what was to be done with philosophical problems was not to solve them, but to dissolve them.