Proudhon sought in his first and larger work, which is mainly of a critical nature, to put forward the negative proof that property is impossible, by inverting all the proofs hitherto brought forward in its favour, so that instead of justifying the possession of property they seemed rather to make for freedom. It is, however, quite wrong to regard this dialectic jugglery as the essence of Proudhon's system. A proof, such as that here proposed by Proudhon, is not only quite inadmissible as logic, but it cannot even be said that Proudhon himself (usually so accurate in this respect) turned out here a really good piece of work. On the one hand he attacks the defenders of property, who, after all, are not very difficult to controvert; while, at the same time, his attempt itself does not always succeed. Of course it does not mean very much when he cleverly riddles the old argument for property drawn from divine right or the right of nature; for in any case he was only attacking dead theories. In the attack on really living arguments, as in the case of his theory of labour, he does not succeed. Property cannot be explained by labour because (1) The land cannot be appropriated, (2) Labour leads to equality, and in the sight of justice labour, on the contrary, abolishes property. The proposition that property, _i. e._, the right to the substance of the thing appropriated, cannot be created by labour, because the land cannot be appropriated, is at least a _petitio principii_ or tautology. But, leaving that, let us suppose that the land really cannot be appropriated; yet there is always some kind of property which has nothing to do with the land. It will not do always to speak of landed property only, as Proudhon invariably does. Movable property (in weapons, utensils, ornaments, animals, etc.) precedes immovable property, owing to its origin, which was only created in imitation of the other much later, and is entirely property due to work; thus not only property, but not even the origin of the idea of property in men, can be explained from the point of view of social history otherwise than by work.