This is the story of David Bohm's hitherto unpublished notes, uncovered from a series of lectures given in Israel in 1957 to a group of Marxist physicists from the Hashomer Hatsair (young guard) movement. The notes explore quantum theory and dialectical materialism, as well as shedding light on the intellectual and emotional resources of his persistent rebellion against orthodoxies in science. The discussion places his lectures notes in a wider historical, scientific, and philosophical context and traces Bohm's intellectual development from an early attempt to better understand the Copenhagen interpretation of quantum mechanics to his elaboration of an alternative causal interpretation based on the notion of 'hidden variables.' As the lecture notes strikingly illustrate, dialectical materialism played a fundamental role for the further development of his understanding of quantum mechanics. Bohm placed the notions of infinity of nature and the unity of opposites in the center of his