5. The Recent Revolution in Natural Science and Philosophical Idealism¶
Core Argument¶
This chapter dissects the ideological fallout from the revolutionary discoveries in physics at the turn of the twentieth century—X-rays, Becquerel rays, radium, and the electron—arguing that these breakthroughs confirm dialectical materialism, not the idealist conclusions drawn by the Machian school. Joseph Diner-Dénes, writing in Die Neue Zeit, directly compared these discoveries with Engels’ Anti-Dühring, concluding that nature, like history, obeys dialectical law: there are no fixed boundaries, chemical elements prove destructible (radium converts into helium), and all forces reduce to one force, all substances to one substance. Motion is the mode of existence of matter. Lenin insists that revising Engels’ natural-philosophical propositions is not revisionism but a demand of Marxism; the Machians are criticised not for revising form but for betraying the essence of materialism while adopting reactionary bourgeois philosophy.
The crisis in physics, articulated by Henri Poincaré, saw the conservation of energy undermined by radium, the conservation of mass by the electron theory (suggesting mass is entirely electrodynamic in origin), and Newton’s principle of action and reaction shaken. Poincaré spoke of “ruins” and a “general debacle of principles”, drawing idealist epistemological conclusions that space and time are imposed by us on nature. Abel Rey’s The Physical Theory of the Modern Physicists summarised the crisis: traditional physics, which assumed a mechanical explanation of nature and ascribed ontological value to its theories, was collapsing. Lenin counters that the real meaning of “matter is disappearing” is that previously absolute properties (impenetrability, inertia, mass) are revealed as relative. The sole property of matter for philosophical materialism is objective reality existing outside the mind.
The chapter contrasts two schools: “physical realists”, who believe they approach ultimate reality, and “physical symbolists” (Kirchhoff, Poincaré, Duhem, Pearson, Mach), who treat theory as a generalised descriptive scheme. The idealist Ward exploits the collapse of old concepts to argue that matter itself has disappeared, leaving only motion divorced from matter. Lenin counters that the electron is as inexhaustible as the atom; nature is infinite but infinitely exists. The crisis stems from the conquest of physics by the mathematical spirit, which reduces material elements to abstractions, and from the principle of relativism, which, ignorant of dialectics, slides into idealism. The basic materialist spirit of physics will overcome all crises by replacing metaphysical materialism with dialectical materialism.