Abstract: To refute the Young Hegelians’ reductive narrative that equated French materialism with a “French Spinozist school”, Marx strategically reconstructed its intellectual tradition, delineating it into two distinct lineages: one derived from Descartes’ mechanistic materialism, and the other stemming from Locke’s humanist materialism. He not only clarified the inherent limitations of the former—which achieved successes in the natural sciences at the cost of sacrificing human subjectivity—but also uncovered the latent, yet incomplete, philosophical potential of the latter, which provided a logical foundation for communism. In doing so, Marx charted the principles and direction for the development of his new materialism. In terms of theoretical impact, the new materialism Marx founded no longer sought to construct a metaphysical system aimed at explaining the ultimate nature of the world. Instead, it committed itself to forging philosophy into a critical weapon for the proletariat, thereby fundamentally transcending the metaphysical constraints of traditional philosophy, which remained entangled in debates over “matter” or “spirit”. This fundamental shift in the philosophical paradigm laid a solid theoretical foundation for the scientific analysis of capitalism and the realization of human emancipation.