In those annals of history which record the noble espousal of lost causes, the name of Ernst Mach is often linked with the opposition to atomic and molecular theories, along with such figures as Ostwald, Stallo, and Duhem. And rightly so, for Mach's writings over a fifty-year period from 1866¹ until 1916 reveal an extreme suspicion of, bordering often on a hostility to, most of the atomistic theories of that period. Moreover, the running dispute between Mach and Boltzmann and later between Mach and Planck centered squarely on the efficacy of atomic and molecular approaches to the explora­tion of natural phenomena. But though the fact of Mach's opposition to atomic/molecular theories is well known and widely cited, Mach's specific argumentative strategies against such theories have been less fully explored and understood. Still less well documented is the relation of Mach's stand on atomism to his other work in philosophy, especially in the area of the logic and epistemology of science. Finally, the relation of Mach's critique of atomism to the views of his scientific and philosophical contemporaries is almost completely unexplored terrain.