Sterrett explains what Wittgenstein's glimpse of a solution to the problem of language in 1914 had to do with experimental models--which had been so crucial to the Wright brothers solving the problem of flight. On the eve of the First World War in Europe, Wittgenstein left aeronautical research to study philosophy. He was deeply dissatisfied with Bertrand Russell's solution to the paradoxes of logic: the theory of types. Meanwhile, across the Atlantic Ocean, a physicist trying to improve U.S. aeronautical research capability pondered how the logic of empirical equations held the key to identifying physically similar situations, which in turn would explain the success of the Wright brothers' airplane built from cardboard cartons and bicycle parts. His conclusion held an answer to Wittgenstein's problems about the logic of propositions. In a profound turning point in the history of human thought, Wittgenstein saw that envisioning a propostion as a model or picture would solve the problems of philosophy. He presented this idea in his now legendary "Tractatus Logico-Philosophicus" and commanded the attention of brilliant minds ever since.