Dialectical Materialism and Science¶

Marxist Theory · 2026-05-13

Core Argument¶

Trotsky's central thesis is that the Marxist method — dialectical materialism — is not merely a political doctrine but the only genuinely scientific approach to understanding society, precisely because it applies the same materialist logic to social phenomena that the natural sciences apply to physical phenomena. The argument proceeds through a sustained comparison: just as chemistry abandoned phlogiston, physiology abandoned vital force, and psychology abandoned the soul, so Marxism abandons the "super-social substances" — national character, historical mission, critical thought — that bourgeois social science uses to explain society. The claim is not that Marxism replaces the natural sciences, but that it provides the methodological bridge between them and a genuinely scientific sociology. Trotsky insists that the test of any science — natural or social — is its capacity to foresee and thereby to act. Marxism passes this test; official bourgeois social science fails it, as demonstrated by its inability to predict war, revolution, or economic crisis.

The speech also makes a secondary argument about the relationship between socialist society and the scientific inheritance of the past. Trotsky introduces the concept of "inventorial inheritance" — the revolutionary state does not accept the cultural past wholesale but selects what serves the development of the productive forces and discards what served only to justify class domination. Natural science, because it is corrected by practical experience with matter itself, constitutes the most valuable portion of this inheritance. Social science, by contrast, has been primarily apologetic and must be reconstructed on Marxist foundations.

Theoretical Grounding¶

The speech is grounded in the classical Marxist understanding of the relationship between base and superstructure, but Trotsky deploys it with unusual precision. He treats ideology not as a mere epiphenomenon but as a "subordinate integral element of the material social structure" — a formulation that avoids both crude economic determinism and the idealist autonomy of ideas. The key theoretical move is the insistence on the relative autonomy of each level of scientific analysis: chemistry cannot be reduced directly to mechanics, nor sociology to physiology, but each is ultimately rooted in the material substratum below it. This is a sophisticated defence of the unity of science without reductionism.

Trotsky draws explicitly on Engels's use of Mendeleyev's Periodic Law as a confirmation of the dialectical law of the transformation of quantity into quality. He also invokes Pavlov's theory of conditioned reflexes as a materialist psychology that eliminates the need for a "soul" — a move that situates the speech within the broader Marxist engagement with the natural sciences in the 1920s, when figures like Bukharin and Haldane were attempting to synthesise Marxism with the latest developments in biology and physics.

The speech sits within the tradition of Marxist philosophy of science that runs from Engels's Dialectics of Nature through to later debates about the relationship between Marxism and the natural sciences. Trotsky's position is distinct from both the positivist tendency to collapse all science into a single method and the idealist tendency to treat Marxism as a substitute for specialised scientific research. His rebuke of "Communist swagger" (Komchvanstvo) — the idea that Marxism can replace chemistry — is balanced by an equally sharp critique of "Chemist swagger" (Khimchvanstvo) — the idea that natural science alone can answer social questions.

Conjunctural Relevance¶

The speech was delivered in September 1925, at a moment when the Soviet Union was emerging from the devastation of civil war and beginning the period of the New Economic Policy. Trotsky was speaking as chairman of the technical and scientific board of industry — a position that gave his words immediate practical weight. The conjuncture is defined by two tensions that run through the text.

First, there is the tension between the revolutionary state's need to develop the productive forces and the danger of bureaucratic ossification. Trotsky's 1938 foreword makes explicit what the 1925 speech only hints at: the hope that Soviet democracy would create favourable conditions for scientific thought had not been realised. The speech is therefore a document of the possibility of a socialist science policy before Stalinism closed it off — a possibility that remains relevant wherever states claim to be building socialism while suppressing genuine scientific inquiry.

Second, there is the geopolitical conjuncture of the mid-1920s: the stabilisation of European capitalism after the revolutionary wave of 1917-1923, the rise of American economic dominance, and the isolation of the Soviet Union. Trotsky's critique of Mendeleyev's faith in international conferences (the Hague, Portsmouth, Morocco) is a pointed reminder that capitalism's "peaceful" institutions produce war, not concord. The reference to Keynes's Malthusianism — "we must busy ourselves with limiting the increase in population" — connects the speech to the longer history of bourgeois attempts to naturalise scarcity, a tendency that has only intensified in the era of climate crisis and austerity.

The speech's relevance to the current conjuncture lies in its defence of the unity of science against both postmodern relativism and technocratic reductionism. In an era when the right weaponises "science" to naturalise market relations and the left sometimes abandons scientific rationality altogether, Trotsky's insistence that Marxism provides the only genuinely scientific method for understanding society — and that this method is continuous with, not opposed to, the natural sciences — is a position that cuts against both poles of contemporary confusion.

Where the Argument Continues¶

The speech leaves several questions open. Trotsky does not develop the relationship between dialectical materialism and the specific discoveries of quantum mechanics or relativity theory, which were transforming physics in the 1920s. This gap is addressed in later IDOM articles on science and Marxism, particularly those engaging with the work of J.B.S. Haldane and the debates about "proletarian science" in the Soviet Union. The question of how Marxism should respond to the ideological uses of science under late capitalism — from evolutionary psychology to climate denial — is a natural extension of Trotsky's critique of "Chemist swagger."

The speech also gestures towards, but does not fully develop, the concept of "inventorial inheritance" as a general theory of cultural transmission under socialism. This argument is taken up in Trotsky's later writings on literature and art, particularly Literature and Revolution, and in the broader Marxist tradition of cultural theory from Lukács to Benjamin.

For readers of the IDOM corpus, the speech should be read alongside Trotsky's other philosophical writings — In Defence of Marxism, his critique of the "ABC of Materialism" — and alongside the ongoing series of articles on dialectical materialism published on marxist.com. The Against the Stream episode on "Marxism and Science" provides a contemporary discussion of the same themes.

Connections¶

Engels, Dialectics of Nature: The direct theoretical ancestor of Trotsky's argument, particularly the sections on the transformation of quantity into quality and the critique of mechanism.
Lenin, Materialism and Empirio-Criticism: The philosophical defence of materialism against idealist currents in physics, though Trotsky's approach is less polemical and more constructive.
Trotsky, Literature and Revolution: The application of the "inventorial inheritance" concept to art and culture.
Trotsky, In Defence of Marxism: The later defence of dialectical materialism against the bureaucratic distortions of Stalinism.
J.B.S. Haldane, The Marxist Philosophy and the Sciences: A contemporary attempt to synthesise Marxism with biology and genetics, written from a position sympathetic to Trotsky's approach.
Georg Lukács, History and Class Consciousness: A parallel but more Hegelian attempt to theorise the relationship between Marxism and science, though Lukács's rejection of Engels's Dialectics of Nature places him in tension with Trotsky's position.

Key Quotes¶

"The essence of Marxism consists in this, that it approaches society concretely, as a subject for objective research, and analyzes human history as one would a colossal laboratory record. Marxism appraises ideology as a subordinate integral element of the material social structure."
"Science is knowledge that endows us with power. When Leverrier on the basis of the 'eccentricities' in the orbit of Uranus concluded that there must exist an unknown celestial body 'disturbing' the movement of Uranus... at that moment the celestial mechanics of Newton celebrated a great victory."
"Chemistry is a school of revolutionary thought not because of the existence of a chemistry of explosives. Explosives are far from always being revolutionary. But because chemistry is, above all, the science of the transmutation of elements; it is hostile to every kind of absolute or conservative thinking cast in immobile categories."
"Whenever any Marxist attempted to transmute the theory of Marx into a universal master-key and ignore all other spheres of learning, Vladimir Ilyich (Lenin) would rebuke him with the expressive phrase: 'Komchvanstvo' ('Communist swagger'). This would mean in this particular case – Communism is not a substitute for chemistry. But the converse theorem is also true."
"If there are no limits to knowledge and mastery of matter, then there is no unknowable 'essence.' Knowledge which arms us with the ability to forecast all possible changes in matter, and endows us with the necessary power of producing these changes – such knowledge does in fact exhaust the essence of matter. The so-called unknowable 'essence' is only a generalization of our inadequate knowledge about matter. It is a pseudonym for our ignorance."
"The German physiologist, Du Bois Reymond once envisaged philosophic thought as departing from the scene of the class struggle and crying out: 'Ignorabimus!' That is, we shall never know, we shall never understand! And scientific thought, linking its fate with the fate of the rising class, replies, 'You lie! The impenetrable does not exist for conscious thought! We will reach everything! We will master everything! We will rebuild everything!'"