With his analyses and visions, Karl Marx became the forerunner of the modern revolution. His demand for the abolition of capitalism has made world history, and our understanding of economics is profoundly shaped by his concepts and ideas such as surplus value, alienation, and class. Even after the failure of communist ideology, his questions about society and the individual, economics and labor, or the preservation of the ecosphere remain highly relevant. Iring Fetscher, one of the most significant Marx researchers in the Federal Republic, has presented an unparalleled knowledgeable introduction to Marx with his concise book. The new edition is supplemented by his influential essay "Liberal, Democratic, and Marxist Concepts of Freedom.".