Boltzmann and epistemology

This paper is an attempt to clarify why Ludwig Boltzmann from about 1895 to 1905 seemed to adopt a series of extreme epistemological positions, rangin g from phenomenalism to pragmatism, while emphatically rejecting what he ca lled 'metaphysics' (by which he meant all traditional philosophy). He concl uded that all philosophical differences were merely linguistic and most wer e ultimately meaningless. But at about the time that young Ludwig Wittgenst ein began absorbing these desperate ideas (1905), Boltzmann himself under t he influence of Franz Brentano seemed to assume a type of representationali sm about the external physical world, while in his own mind adopting it for pragmatic reasons. Why? Because "it worked''. He seems to have defended hi s non-representationalist Bildtheorie on similar grounds, but his suicide f ollowed shortly (1906).