"Long before me, bourgeois historians had described the historical development of this struggle between the classes, as had bourgeois economists their economic anatomy. My own contribution was (1) to show that the existence of classes is merely bound up with certain historical phases in the development of production; (2) that the class struggle necessarily leads to the dictatorship of the proletariat; [and] (3) that this dictatorship, itself, constitutes no more than a transition to the abolition of all classes and to a classless society"