Dialectical logic

This article is about the Hegelian and Marxist method. For the formalisation of dialectic in logic, see Logic and dialectic. For other uses, see Dialectical logic (disambiguation).

Dialectical logic was the system of laws of thought, developed within the Hegelian and Marxist traditions, that sought to supplement or replace the laws of formal logic. The precise nature of the relation between dialectical and formal logic was hotly debated within the Soviet Union and China.

Rather than the abstract formalism of traditional logic, dialectical logic was meant to be a materialistic examination of concrete forms: The logic of motion and change. A logic that is a statement about the objective material world.

Stalin argued in his Marxism and Problems of Linguistics that there was no class content to formal logic and that it was an acceptable neutral science. This led to the insistence that there were not two logics, but only formal logic. The analogy used was the relation of elementary and higher mathematics. Dialectical logic was hence concerned with a different area of study than formal logic.

The main consensus among dialecticians was that dialectics did not violate the law of contradiction of formal logic, although attempts were made to create a paraconsistent logic.

Some Soviet philosophers argued that the materialist dialectic could be seen in the mathematical logic of Bertrand Russell. But this was criticized by Deborin and the Deborinists as panlogicism.

Evald Ilyenkov held that logic was not a formal science but a reflection of scientific praxis. The rules of logic are not independent of the content. He followed Hegel in insisting that formal logic had been sublated. Logic needed to be a unity of form and content and to state actual truths about the objective world. Thought needs to be realized in life. He used Das Kapital to illustrate the constant flux of A and B and the vanity of holding strictly to either A or -A. Self-development is inherently a logical contradiction.

During the Sino-Soviet split, dialectical logic was used in China as a symbol of Marxism–Leninism against the Soviet rehabilitation of formal logic.