The State and Revolution (1917), by Vladimir Lenin, describes the role of the State in society, the necessity of proletarian revolution, and the theoretic inadequacies of social democracy in achieving revolution to establish the dictatorship of the proletariat.

Lenin's direct and simple definition of the State is that "the State is a special organisation of force: it is an organisation of violence for the suppression of some class." Lenin declared that the task of the Revolution was to smash the State.

This work is considered to be Lenin's most important contribution to political theory and has been called his greatest work on the state.

Capital, Vol. 2: The Process of Circulation of Capital is the "forgotten" second volume of Karl Marx's world-shaking analysis of economics, politics, and history. This essential part of Marx's work contains the vital discussion of commodity, which is the cornerstone of Marx's theories.

Marx delves into the nature of the marketplace in bourgeois society, arguing that prosperity in a capitalist society inevitably holds within itself the seeds of its own destruction. This immensely powerful work is a vital cornerstone to Marx’s overall theory of economics.