Here we have a thorough-going system of materialist monism. "Ours is the organic conception of history," says Labriola. "The totality of the unity of social life is the subject matter present to our minds. It is economics itself which dissolves in the course of one process, to reappear in as many morphological stages, in each of which it serves as a substructure for all the rest. Finally, it is not our method to extend the so-called economic factor isolated in an abstract fashion over all the rest, as our adversaries imagine, but it is, before everything else, to form an historic conception of economics, and to explain the other changes by means of its changes."[11] In another place he says: "Ideas do not fall from heaven, and nothing comes to us in a dream.... The change in ideas, even to the creation of new methods of conception, has reflected little by little the experience of a new life. This, in the revolutions of the last two centuries, was little by little despoiled of the mythical, religious and mystical envelopes in proportion as it acquired the practical and precise consciousness of its immediate and direct conditions. Human thought, also, which sums up this life and theorizes upon it, has little by little been plundered of its theological and metaphysical hypotheses to take refuge finally in this prosaic assertion: in the interpretation of history we must limit ourselves to the objective co-ordination of the determining conditions and of the determined effects." He reiterates: "Ideas do not fall from heaven; and, what is more, like the other products of human activity, they are formed in given circumstances, in the precise fulness of time, through the action of definite needs, thanks to the repeated attempts at their satisfaction, and by the discovery of such and such other means of proof which are, as it were, the instruments of their production and their elaboration. Even ideas involve a basis of social conditions; they have their technique; thought also is a form of work. To rob the one and the other, ideas and thought, of the conditions and environment of their birth and their development, is to disfigure their nature and their meaning."[12] This socialist materialism does not refuse the inspiration of ideals. "By granting that society is dominated by material interests," Dietzgen explains, "we do not deny the power of the ideals of the heart, mind, science, and art. For we have no more to deal with the absolute antithesis between idealism and materialism, but with their higher synthesis which has been found in the knowledge that the ideal depends on the material, that divine justice and liberty depend on the production and distribution of earthly goods."[13]