Maoist philosophical theory: Mao directly bases his teaching on the writings of Marx, Engels and Lenin. Philosophically, his most important reflections emerge on the concept "contradiction". These are contained in two major essays: “On contradiction” and “Contradictions of the people”. He adopts therein the positivist-empiricist idea (shared by Engels) that contradiction is present in matter itself (and thus, also in the ideas of the brain). Matter always develops through a dialectical contradiction. Thanks to this unfolding, something that was subordinated in the past may become dominant in the present and the future. This should be directly read in the light of the principle of class struggle. Furthermore, each contradiction (let us say class struggle: the contradiction holding between relations of production and the concrete development of forces of production) expresses itself in a series of other contradictions, some of which are dominant, others not. The former should be tackled with priority when trying to make the basic contradiction develop, or rather dissolve.  

 His basic stand on contradiction is connected with Marxist epistemology, and also with politics. The two essays just quoted contain reflections on this issue, but we must add to it those developed in the essay “On practice”. “Practice” articulates "contradiction" with "class struggle" in the following way. Inside a mode of production, there are 3 realms where practice functions: economic production, scientific experimentation (which also takes place in economic production and shouldn't be radically disconnected from the former) and finally class struggle. These may be considered the proper objects of economy, scientific knowledge and politics. The three of them deal with matter in its various forms, socially mediated. As a result, they are the only realms where knowledge may arise (since truth and knowledge only make sense in relation to matter). Mao emphasizes –like Marx in trying to confront bourgeoisie idealism of his time- that knowledge must count with empirical evidence. Knowledge result from hypotheses verified in the contrast with a real object; this real object, despite being mediated by the subject’s theoretical frame, retains its materiality and will offer resistance to those ideas that do not conform to its truth. Thus, in each of these realms (economic, scientific and political practice), contradictions (principle and secondary) must be identified, explored and put to function to achieve the communist goal.