The following is from the website of the Communist Party of Great Britain (Marxist-Leninist):
Theory: Mao’s ‘On contradiction’
A masterly exposition of how to use dialectics to change the world by the leader of the Chinese revolution.
Mao wrote the article ‘On contradiction’ in 1937 to explain the dialectical method of analysis. He did this to counter the development of dogmatic approaches to study and practice that had developed within the Chinese Communist Party.
He also sought to explain international events, particularly the struggle between Marxist-Leninist leadership and the right and, later, left opportunism within the Communist Party of the Soviet Union.