Law of the Unity of Opposites

Also known as the “law of contradiction”. The law of the unity of opposites is one of the basic laws of materialist dialectics.

Engels expressed the law of the unity of opposites as “the law of the interpenetration of opposites”. Lenin pointed out: “The division of a unity into two parts and recognition of its contradictory parts constitute the essence of dialectics.” In On Contradiction, Mao Zedong gave a comprehensive and profound account of the content of the law of unity of opposites and its place in materialist dialectics, and explained the two world outlooks, the universality of contradiction, the particularity of contradiction, the principal contradiction and the principal aspect of a contradiction, the identity and struggle of the aspects of a contradiction, and the place of antagonism in contradiction. Mao Zedong applied the law of the unity of opposites to the practice of Chinese revolution and construction and put forth a series of thinking and working methods for grasping unity in opposition and for knowing and analyzing opposition in unity.

In the system of materialist dialectics, which consists of a series of laws and categories, such as the law of the unity of opposites, the law of the transmutation between quality and quantity and the law of the negation of the negation, the law of the unity of opposites is its essence and core. This is because the law of the unity of opposites reveals that the inherent contradictions within things are the intrinsic ground of the self-movement and the self-development of things; it reveals the fundamental contents of the universal interconnection and the inherent driving forces of the eternal development of things; the unity of opposites is the central clue that runs through the law of the transmutation between quality and quantity and the law of the negation of the negation, and is the “key” to understand these laws and categories; the law of the unity of opposites provides the fundamental method for knowing and reshaping the world—the method of contradiction analysis.