Karl KautskyKarl Johann Kautsky (; ; 16 October 1854 – 17 October 1938) was a Czech-Austrian philosopher, journalist, and Marxist theoretician. Kautsky was one of the most authoritative promulgators of orthodox Marxism after the death of Friedrich Engels in 1895 until the outbreak of World War I in 1914. He was the most important socialist theorist during the years of the Second International. He founded the socialist journal ''Neue Zeit''.
Following the war, Kautsky was an outspoken critic of the Bolshevik Revolution, engaging in polemics with Vladimir Lenin, Leon Trotsky, and Joseph Stalin on the nature of the Soviet state. Provided by Wikipedia
Les trois sources du marxisme : l'oeuvre de Marx. Idéologie et lutte de classes. Le 'renégat' Kautsky et son disciple Lénine