Djamil and Donald join Helena Sheehan, author of Marxism and the Philosophy of Science: A Critical History for a deep dive on the interactions between these two fields. They start off with Sheehan’s intellectual history, before discussing what Marxism is and how it relates to other philosophies of science. They talk about Marx & Engels’ relationship to science, in particular to Darwinism, Engels’ much maligned Dialectics of Nature, its relationship to Hegel, and the laws of dialectics. They continue with the Austromarxists and Neokantianism, its influence on Bogdanov and the Bolshevik Machists, and Lenin’s reply in Materialism and Empirio-criticism. They also discuss the criterium of practice, Bukharin’s philosophy of science and his influence via Science at the Crossroads on a generation of British Marxists including Bernal, Haldane and Caudwell. They finish with discussing the cold & warm split in Marxism.