The Poverty of Philosophy
The present work was produced in the winter of 1846-47,at a time when Marx had cleared up for himself the basic features of his new historical and economic outlook. Proudhon's systeme des contradictions economiques,ou philosophie de la misere, which had just appeared, gave him the opportunity to develop these basic features in opposing them to the views of a man who from then on, was to occupy the chief place among living French socialists. From the time when the two of them in Paris often spent whole nights in discussing economic questions, their paths had more and more diverged: Proudhon's book proved that there was already an unbridgeable gulf between them. To ignore it was at that time impossible, and so Marx by this answer of his put on record the irreparable rupture.