Lukacs' text is comprised of two parts: I. Problems of Class Consciousness, II. Dialectic of Nature. Lukacs defends his seminal work History and Class Consciousness (1923) against his principal intellectual attackers in the Comintern, Abram Deborin and Laszlo Rudas. Lukacs argues that his book is a philosophical expression of Bolshevism and characterizes Deborin as a Menshevik and Rudas as a tailist. Lukacs convincingly argues that these two, operating with an implicit Kantianism and uncritically importing a limited natural-scientific perspective into Marxist theory, are trapped in a subject-object dualism they cannot overcome and have missed the boat on the nature of dialectical consciousness and revolutionary praxis. Part II is of especial importance. Lukacs' criticisms of Engels' dialectics of nature and his remarks about the `contemplative' nature of scientific experiment have always been controversial, but here we see that the real issue for Lukacs is the misbegotten transposition of a dialectic of nature to social theory (on the part of Rudas and Deborin), effecting a fundamental distortion of Marxism. Lukacs harbors no animus against the notion of a dialectic of nature per se, but he offers an interesting if obscure argument that such a bare bones dialectic cannot even do justice to the dialectics of scientific practice, let alone account for the social determination of scientific practice.