756 EVOLUTION tion as a dialectic process. 1 At the same time, we may find expressed in figurative language the germs of thoughts which enter into still newer doctrines of evolution. For example, the notion of conflict (Tro Ae^os) as the father of all things and of harmony as arising out of a union of dis cords, 2 and again of an endeavour by individual things to maintain themselves in permanence against the universal process of destruction and renovation, cannot but remind one of certain fundamental ideas in Mr Darwin s theory of evolution. According to Grote, it is doubtful how far Heraclitus intended to supply by his idea of fire a physical, as distinguished from a metaphysical, doctrine of the world- process. Empedodes. Empedocles took an important step in the direction of modern conceptions of physical evolution by teaching that all things arise, not by transformations of some primitive form of matter, but by various combinations of a number of permanent elements. Further, by maintaining that the elements are continually being combined and separated by the two forces love and hatred, which appear to represent in a figurative way the physical forces of attraction and repulsion, Empedocles may be said to have made a considerable advance in the construction of the idea of evolution as a strictly mechanical process. It may be observed, too, that the hypothesis of a primitive compact mass (sphcerus), in which love (attraction) is supreme, has some curious points of similarity to, and contrast with, that notion of a primitive nebulous matter with which the modern doctrine of cosmic evolution usually sets out. Empedocles tries to explain the genesis of organic beings, and, according to Lange, anticipates the idea of Mr Darwin that adaptations abound, because it is their nature to perpetuate themselves. He further recognizes a pro gress in the production of vegetable and animal forms, though this part of his theory is essentially crude and unscientific. More important in relation to the modern problems of evolution is his thoroughly materialistic way of explaining the origin of sensation and knowledge by help of his peculiar hypothesis of effluvia and pores. The sup position that sensation thus rests on a material process of absorption from external bodies naturally led up to the idea that plants and even inorganic substances are pre- cipient, and so to an indistinct recognition of organic life as a scale of intelligence. Anaxagoras. The doctrine of Homoemeries, propounded by Anaxagoras, agrees with that of Empedocles in assign ing the origin of things to combinations and redistributions of certain primordial forms of matter. Yet these are less simple than the elements of the other thinker. 3 Moreover, the idea that the diversity of things arises from a preponderance of certain elements, and not from the mere fact of various combination, removes the theory of Anaxagoras further from modern conceptions of cosmic evolution than that of Empedocles. 4 According to Grote s interpretation, Anaxagoras, in his conception of nous as the originator of movement and order which manifests itself as the vital principle in plants as well as in animals and man, 1 This is brought out by F. Lassalle, Die Philosophic Herakleitos, 2 Zeller observes that Heraclitus fails to tell us what are the elements which conflict. 3 Grote says the idea of these multifarious forms of matter was su<*- gested by the phenomena of animal nutrition. Plato, i. 55. It is observed by Ferrier that the doctrine of Anaxagoras reverses the order of the Atomists, by regarding the transition as one from the complex to the seemingly simple. It is no doubt true that the chief aim 01 Anaxagoras was to explain not so much the diversity as the orderly arrangement of individual things. Yet his conception of the mmal i chaps involves at least the notion of an apparent homogeneitv formity, no particles being distinguishable from the rest. (See tafX P i- Gr te even <assimilat es the chaos of Anaxagoras to the primordial indeterminate of Anaximander. would appear to lean rather to a monistic and purely materialistic than to a dualistic conception of evolution. Atomists. In the theory of Atomism taught by Leucip- pus and Democritus we have the basis of the modern mechanical conceptions of cosmic evolution. Here the endless harmonious diversity of our cosmos, as well as of other worlds supposed to co-exist with our own, is said to arise through the various combination of indivisible material elements differing in figure and magnitude only. The force which brings the atoms together in the forms of objects is inherent in the elements, and all their motions are necessary. The origin of things, which is also their substance, is thus laid in the simplest and moat homogeneous elements or principles. The real world thus arising consists only of diverse combinations of atoms, having the properties of magnitude, figure, weight, and hardness, all other qualities being relative only to the sentient organism. The problem of the genesis of mind is practically solved by identifying the soul, or vital principle, with heat or fire which pervades in unequal proportions, not only man and animals, but plants atid nature as a whole, and through the agitation of which by incoming effluvia all sensation arises. The Sophists Critias. Of the Sophists there is but one whose doctrine need concern us here, namely, Critias. In a fragment of his writings we meet with a speculation on the past development of man, which is curious as distinctly recognizing the upward direction of human history, and so as contrasting with the prevailing view of this history as a gradual deterioration. Critias tells us there was a time when the life of man was lawless (ara/o-os) and beast-like (^T/piwS^s), when he was a slave of force, and when no honour was paid to the good nor punish ment administered to the bad. Laws having arisen, evil actions which could no longer be done overtly were still practised in secret, and at this stage a wise man arose who sought to instil terror into the minds of the people, and so conceived the Deity, who is made the more terrible by being localized in the region whence proceed thunder and lightning. Plato. Plato needs to be referred to here only because of the strongly marked opposition of his philosophy to the teaching of evolution. It is true (as Zeller remarks) that Plato s whole philosophy was directed less to the explana tion of becoming than to the consideration of being. So far, however, as the highly mythical cosmology of the Timceus may be taken as indicating Plato s way of looking at the successive order of the world, we see that it widely deviates from that of the evolutionist. Thus the notion of the Demiurgus is distinctly contradictory of the idea of a natural process of evolution. Again, the supposition that the world of particular things is somehow determined by pre-existing universal ideas lends itself rather to a theory of emanation as a descent from the more perfect to the less perfect than to a doctrine of evolution. It became the basis of that doctrine of universal essences or types which for ages interfered with a scientific explanation of organic forms. Again Plato exactly reverses the order of evolution in his way of looking at the scale of organic beings and souls, since he sets out with the highest and most perfect, the divine cosmos, and passes downwards to man and the lower animals viewed as successive degradations. Early Platonists. Among the early followers of Plato, Speusippus deserves mention here in so far as he assimilated the course of the world to the development of the individual by regarding it as a progress from imperfection to per fection. 5 Xenocrates again appears to have viewed the 5 Speusippus differed from Plato by making good the end and not
the efficient cause of being (see Zeller, Plato, p. 568 .sq.).