The Communist Manifesto — Marx & Engels (1848)

Marx and Engels's 23-page pamphlet — "Workers of the world, unite!" — became the ideological foundation for communist movements that governed a third of humanity during the 20th century. Its analysis of capitalism as a class system driven by exploitation of labour, whatever its prescriptive failures, remains one of the most penetrating critical frameworks for understanding market societies and still shapes academic discourse in sociology, economics, and political science.