In 1913, Lenin wrote a brilliant short sketch called "The three sources and component parts of Marxism'.¹ I shall here indicate, following Lenin, what those components were. But I shall strive to do a bit better than Lenin (in this particular respect!) by displaying more clearly than he did how the three parts of Marxism that he identified were so combined by Marx as to make each part far more illuminating and consequential than it was in the isolated condition in which Marx found it.