Karl Marx, who made very merry over Proudhon's dialectic, thought he had played his trump card against the capitalistic method of production in almost the same way, namely, with the Hegelian proposition of the negation of negation. If they both explained themselves by bringing forward, besides the dialectic proof, also an historical and economic one for their contentions, the answer is that historic proof cannot be brought forward for Proudhon's synthetic conception of property or for Marx's method of production, since history only concerns itself with the past or the present; whereas such conditions as they imagine exist only in the future, and can only be derived from the past or present conditions by the dialectic method, and only can be assumed as hypotheses. This standpoint unites Proudhon and Karl Marx, the Anarchists and the Social Democrats; they both call each other Utopians, and both are right. * * * * * Proudhon in his book upon property did not answer the question put in its title, _What is Property?_ as he had promised in the introduction. From his statement "property is theft," which was uttered with so much _eclat_, and of which, according to his own account at least, he was prouder than if he had possessed all the millions of Rothschild--from this paradox one might conclude, and certainly the great majority of his readers do conclude usually that Proudhon was an enemy of property in general. That is not at all the case. "What I have been seeking since 1840 in defining property," said he much later (in _Justice_, i., p. 302), "and what I wish to-day, as I have repeated over and over again, is certainly not abolition of property. For this would be to fall into Communism with Plato, Rousseau, Louis Blanc, and other opponents of property, against whom I protest with all my strength. What I demand from property is _a balance_." But all his life Proudhon was unable to dispel the misunderstanding which he carelessly brought upon his doctrine in his first writing by a talented paradox. We say carelessly, for the concluding answer which Proudhon gives to the question, "What is property?" was, even in his first work, not "property is theft" but "property is liberty;" only the use of all his great scientific apparatus was quite superfluous, because it was in no way connected with the chief purpose of his book. Proudhon might just as well have placed the supposed conclusion, the Ten Commandments of his economic doctrine, at the beginning of his book, for they were arrived at not by the method of science but of speculation. These Ten Commandments run: