Many commentators agree that Wittgenstein took the idea that propositions are Bilder, or at least the terminology of Bilder, from Heinrich Hertz, or from Hertz and Ludwig Boltzmann. Boltzmann, the great Viennese theoretical physicist, was the founder of statistical thermodynamics, the modern theory of heat. The context within which Hertz and Boltzmann worked was one in which many prominent theoretical physicists accepted the Kantian restriction that our thought cannot access 'things in themselves', but works only with representations. Wittgenstein may have (...) found what Hertz said attractive, but even if he did develop a theory of representation or a picture theory of meaning, neither was something that he just took over from Hertz, fully formed, and his main concerns were puzzles about intentionality, not science. Hertz and Boltzmann did influence various aspects of the Tractatus. Their greatest and most lasting influence on Wittgenstein, though, was on his conception of philosophy itself: its aim, and its method. (shrink)