760 EVOLUTION prominent this idea, namely, Bodin, Bacon, Descartes, and Pascal. The former distinctly argues against the idea of a deterioration of man in the past. In this way we see that just as advancing natural science was preparing the way for a doctrine of physical evolution, so advancing historical re- nearch was leading to the application of a similar idea to the collective human life. English Writers of the 18th Century Hume. The theo logical discussions which make up so large a part of the English speculation of the last century cannot detain 1*5 here. There is, however, one writer who sets forth so clearly the alternative suppositions respecting the origin of the world that he claims a brief notice. We refer to David Hume, In his Dialogues concerning Natural Re ligion he puts forwards tentatively, in the person of one of his interlocutors, the ancient hypothesis that since the world resembles an animal or vegetal organism rather than a machine, it might more easily be accounted for by a pro cess of generation than by an act of creation. Later on he develops the materialistic view of Epicurus, only modify ing it so far as to conceive of matter as finite. Since a finite number of particles is only susceptible of finite trans positions, it must happen (he says), in an eternal duration that every possible order or position will be tried an infinite number of times, and hence this world is to be regarded (as the Stoics maintained) as an exact reproduction of previous worlds. The speaker seeks to make intelligible the appearance of art and contrivance in the world as a result of a natural settlement of the universe (which passes through a succession of chaotic conditions) into a stable condition, having a constancy in its forms, yet without its several parts losing their motion and fluctuation. Priestley. The English materialists of the latter part of the century did little to work out the idea of evolution. Priestley needs to be mentioned here only by reason of his clear recognition of human progress. Monboddo. Of other British writers of the period, Lord Monboddo must be named on account of his curious speculations respecting the origin of man. In his Ancient Metaphysics (vol. iii.), Monboddo conceives man as gradually elevating himself from an animal condition, in which his mind is immersed in matter, to a state in which mind acts independently of body. In his equally voluminous work, The Origin and Progress of Language, Monboddo brings man under the same species as the orang-outang. He traces the gradual elevation of man to the social state, which he conceives as a natural process determined by " the necessities of human life." He looks on language (which is not " natural " to man in the sense of being necessary to his self-preservation) as a consequence of his social state. French Writers of the 18th Century. Lei us now pass to the French writers of the last century. Here we are first struck by the results of advancing physical speculation in their bearing on the conception of the world. Careful attempts, based on new scientific truths, are made to explain the genesis of the world as a natural process. Maupertuis, who, together with Voltaire, introduced the new idea of the universe as based on Newton s discoveries, sought to account^ for the origin of organic things by the hypothesis of sentient atoms. Buffon the naturalist speculated, not only on the structure and genesis of organic beings, but also on the course of formation of the earth and solar system, which he conceived after the analogy of the development of organic beings out of seed. Diderot, too, in his varied in tellectual activity, found time to speculate on the genesis of sensation and thought out of a combination of matter endowed with an elementary kind of sentience. De la Mettrie worked out a materialistic doctrine of the origin of things, according to which sensation and consciousness are nothing but a development out of matter. He sought (L homme-machine) to connect man in his original condition with the lower animals, and emphasized (L homme-plante) the essential unity of plan of all living things. Helvetius, in his work on man, referred all differences between our species and the lower animals to certain peculiarities of organization, and so prepared the way for a conception of human development out of lower forms as a process of physical evolution. Charles Bonnet met the difficulty of the origin of conscious beings much in the same way as Leibnitz, by the supposition of eternal minute organic bodies to which are attached immortal souls. Yet though in this way opposing himself to the method of the modern doctrine of evolution, he aided the development of this doctrine by his view of the organic world as an ascend ing scale from the simple to the complex. Robinet, in his treatise De la Nature, worked out the same conception of a gradation in organic existence, connecting this with a general view of nature as a progress from the lowest inorganic forms of matter up to man. The process is con ceived as an infinite series ef variations or specifications of one primitive and common type. Man is the cliff d oeuvre of nature, which the gradual progression of beings was to have as its last term, and all lower creations are regarded as pre-conditions of man s existence, since nature " could only realize the human form by combining in all imaginable ways each of the traits which was to enter into it." The formative force in this process of evolution (or " metamor phosis ") is conceived as an intellectual principle (idee generatrice). Robinet thus laid the foundation of that view of the world as wholly vital, and as a progressive unfolding of a spiritual formative principle, which was afterwards worked out by Schelling. It is to be added that Robinet adopted a thorough-going materialistic view of the depen dence of mind on body, going even to the length of assign ing special nerve-fibres to the moral sense. The system of Holbach seeks to provide a consistent materialistic view of the world and its processes. Mental operations are identified with physical movements, the three conditions of physical movement, inertia, attraction, and repulsion, being in the moral world self-love, love, and hate. He left open the question whether the capability of sensation belongs to all matter, or is confined to the combinations of certain materials. He looked on the actions of the individual organism and of society as determined by the needs of self- preservation. He conceived of man as a product of nature that had gradually developed itself from a low condition, though he relinquished the problem of the exact mode of his first genesis and advance as not soluble by data of experience. Holbach thus worked out the basis of a rigorously materialistic conception of evolution. The question of human development which Holbach touched on was one which occupied many minds both in and out of France during the past century, and more especially towards its close. The foundations of this theory of history as an upward progress of man out of a barbaric and animal condition were laid by Vico in his celebrated work Principii di Scienza Nuova. In France the doctrine was represented by Turgot and Condorcet. Of the English writers who discussed the question of man s development we have already spoken. The German speculations on the subject will be touched on presently. German Writers of the 18th Century "Leibnitz. In Leibnitz we find, if not a doctrine of evolution in the strict sense, a theory of the world which is curiously related to the modern doctrine. The chief aim of Leibnitz is no doubt to account for the world in its static aspect as a co-existent whole, to conceive the ultimate reality of things in such a way as to solve the mystery of
mind and matter. Ytt by his very mode of solving the