predecessors and published them to the world with naive pride. Through page after page of argument he holds the reader in expectation of the explanation, which he is about to give, of the nature of value, which he rightly characterises as the "corner-stone of political economy." At last he will disclose the secret: "It is time to make ourselves acquainted with this power. This power ... is _labour_." His main work, "The System of Economic Contradictions," swarms with philosophical formulae and expressions like thesis, antithesis, antinomies, synthesis, dialectics, induction, syllogisms, etc., as also with Latin, Greek, and Hebrew etymologies; it often wanders into irrelevant theological and philosophical digressions and side issues, not so much with the intention of parading the author's knowledge as from his lack of intellectual discipline and insufficient command of his material. The work in question was to combine German philosophy with French and English political economy, and its author believed that it would secure for him before everything else the admiration of the German Socialists, especially of Marx. He drew the latter's attention to it by letter, and awaited his "rigorous criticism." The criticism came in "Misere de la Philosophie" (Brussels, 1847), but it could no longer fulfil its purpose, as the fundamental difference between the two men had already widened to a gulf that could not be bridged. Marx had almost completed his materialistic, logical, and revolutionary Socialism, Proudhon had laid the foundations of his peaceful Anarchism with its federative economic basis. With his searching analysis, his systematised knowledge, and his great indignation at the presumptuous attacks on every Socialist school and leader, Marx sat in judgment upon Proudhon, exposing him as a dilettante in philosophy and economics, and at the same time sketching in outline his own conception of history and economics.