Science of Logic

Hegel's Science of Logic (1812–1816) is the systematic account of pure thought thinking itself. Its subject is not formal logic but the structure of being as revealed by following thought to its necessary conclusions.

The Logic begins with the most abstract thought possible: pure Being, with no determination at all. Pure being and pure nothing are indistinguishable; their unity is Becoming. From this simplest dialectical movement Hegel develops the entire structure of categories: quality, quantity, measure, essence, existence, substance, causality, and finally the Concept (Begriff), in which thought and being are fully united. Each category generates its opposite, and the contradiction resolves at a higher level, not by splitting the difference between the opposed terms but by showing both to be one-sided expressions of a richer unity.

The Logic is the skeleton of Hegel's entire system. The Phenomenology of Spirit shows how consciousness arrives at the standpoint the Logic requires; the Encyclopedia of the Philosophical Sciences applies the logical categories to nature and to spirit. The book is difficult because it refuses to presuppose any prior standpoint: the reader has to follow the thought from the inside, without stepping outside it to check against something else.

Marx retained the dialectical structure while rejecting the idealism: instead of the self-movement of the Concept, he posited the self-movement of material conditions. Every subsequent engagement with dialectical method, whether as continuation, critique, or caricature, begins here.