Criticisms of the labor theory of value affect the historical concept of labor theory of value (LTV) which spans classical economics, liberal economics, Marxian economics, neo-Marxian economics, and anarchist economics. As an economic theory of value, LTV is central to Marxist social-political-economic theory and later gave birth to the concepts of labour exploitation and surplus value. LTV criticisms therefore often appear in the context of economic criticism, not only for the microeconomic theory of Marx but also for Marxism, according to which the working class is exploited under capitalism.