is not the forms of consciousness which determine the human being, but it is the manner of being which determines the consciousness (Marx). But these forms of consciousness, even as they are determined by the conditions of life, constitute in themselves also a part of history. This does not consist only in the economic anatomy, but in all that combination which clothes and covers that anatomy even up to the multicolored reflections of the imagination. In other words, there is no fact in history which does not recall by its origin the conditions of the underlying economic structure, but there is no fact in history which is not preceded, accompanied and followed by determined forms of consciousness, whether it be superstitious or experimental, ingenuous or reflective, impulsive or self-controlled, fantastic or reasoning. IV. I was saying a moment ago that our doctrine makes history objective and in a certain sense naturalizes it, going from the explanation of the data, evident at first sight, of the personalities acting with design, and of the auxiliary conceptions of the action, to the causes and the motives of the will and the action, in order to find thereupon the co-ordination of these causes and of these motives in the pre-elementary _processus_ of the production of the immediate means of existence. Now this term "naturalizing" has led more than one mind into confusing this order of problems with another order of problems, that is to say, into extending to history the laws and the manners of thinking which have already appeared suitable to the study and explanation of the material world in general and of the animal world in particular. And because Darwinism succeeded in carrying, thanks to the principle of the transformation of species, the last citadel of the metaphysical fixity of things, and in discerning, in the organisms, phases, as it were, and moments of a real and proper natural history, it has been imagined that it was a commonplace and simple enterprise to borrow for an explanation of the future and the history of human life the concepts, the principles and the methods of examination to which that animal life is subjected which in consequence of the immediate conditions of the struggle for existence is unfolding to topographical environments not modified by the action of labor. Darwinism, political and social, has, like an epidemic, for many years invaded the mind of more than one thinker, and many more of the advocates and declaimers of sociology, and it has been reflected as a fashionable habit and a phraseological current even in the daily language of the politicians.