The ancient roots of Darwinism

1. Ancient Greek Views

Evolution is not so much a modern discovery as some of its advocates would have us believe. It made its appearance early in Greek philosophy, and maintained its position more or less, with the most diverse modifications, and frequently confused with the idea of emanation, until the close of ancient thought. The Greeks had, it is true, no term exactly equivalent to " evolution"; but when Thales asserts that all things originated from water; when Anaximenes calls air the principle of all things, regarding the subsequent process as a thinning or thickening, they must have considered individual beings and the phenomenal world as, a result of evolution, even if they did not carry the process out in detail. Anaximander is often regarded as a precursor of the modem theory of development. He deduces living beings, in a gradual development, from moisture under the influence of warmth, and suggests the view that men originated from animals of another sort, since if they had come into existence as human beings, needing fostering care for a long time, they would not have been able to maintain their existence. In Empedocles, as in Epicurus and Lucretius, who follow in Hs footsteps, there are rudimentary suggestions of the Darwinian theory in its broader sense; and here too, as with Darwin, the mechanical principle comes in; the process is adapted to a certain end by a sort of natural selection, without regarding nature as deliberately forming its results for these ends.

If the mechanical view is to be found in these philosophers, the teleological occurs in Heraclitus, who conceives the process as a rational development, in accordance with the Logos and names steps of the process, as from igneous air to water, and thence to earth. The Stoics followed Heraclitus in the main lines of their physics. The primal principle is, as with him, igneous air. only that this is named God by them with much greater definiteness. The Godhead has life in itself, and develops into the universe, differentiating primarily into two kinds of elements the finer or active, and the coarser or passive. Formation or development goes on continuously, under the impulse of the formative principle, by whatever name it is known, until all is once more dissolved by theekpyrosis into the fundamental principle, and the whole process begins over again. Their conception of the process as analogous to the development of the seed finds special expression in their term of logos spermatikos. In one point the Stoics differ essentially from Heraclitus. With them the whole process is accomplished according to certain ends indwelling in the Godhead, which is a provident, careful intelligence, while no providence is assumed in Heraclitus.

Empedocles asserts definitely that the sphairos, as the full reconciliation of opposites, is opposed, as the superior, to the individual beings brought into existence by hatred, which are then once more united by love to the primal essence, the interchange of world-periods thus continuing indefinitely. Development is to be found also in the atomistic philosopher Democritus; in a purely mechanical manner without any purpose, bodies come into existence out of atoms, and ultimately entire worlds appear and disappear from and to eternity. Like his predecessors, Deinocritus, deduces organic beings from what is inorganic-moist earth or slime.

Development, as well as the process of becoming, in general, was denied by the Eleatic philosophers. Their doctrine, diametrically opposed to the older thoroughgoing evolutionism, had its influence in determining the acceptance of unchangeable ideas, or forms, by Plato and Aristotle. Though Plato reproduces the doctrine of Heraclitus as to the flux of all things in the phenomenal world, he denies any continuous change in the world of ideas. Change is permanent only in so far as the eternal forms stamp themselves upon individual objects. Though this, as a rule, takes place but imperfectly, the stubborn mass is so far affected that all works out as far as possible for the best. The demiurge willed that all should become as far as possible like himself; and so the world finally becomes beautiful and perfect. Here we have a development, though the principle which has the most real existence does not change; the forms, or archetypal ideas, remain eternally what they are.

In Aristotle also the forms are the real existences, working in matter but eternally remaining the same, at once the motive cause and the effectual end of all things. Here the idea of evolution is clearer than in Plato, especially for the physical world, which is wholly dominated by purpose. The transition from lifeless to living matter is a gradual one, so that the dividing-line between them is scarcely perceptible. Next to lifeless matter comes the vegetable kingdom, which seems, compared with the inorganic, to have life, but appears lifeless compared with the organic. The transition from plants to animals is again a gradual one. The lowest organisms originate from the primeval slime, or from animal differentiation; there is a continual progression from simple, undeveloped types to the higher and more perfect. As the highest stage, the end and aim of the whole process, man appears; all lower forms are merely unsuccessful attempts to produce him. The ape is a transitional stage between man and other viviparous animals. If development has so important a work in Aristotle's physics, it is not less important in his metaphysics. The whole transition from potentiality to actuality (from dynamis toentelecheia) is nothing but a transition from the lower to the higher, everything striving to assimilate itself to the absolutely perfect, to the Divine. Thus Aristotle, like Plato, regards the entire order of the universe as a sort of deification. But the part played in the development by the Godhead, the absolutely immaterial form, is less than that of the forms which operate in matter, since, being already everything,, it is incapable of becoming anything else. Thus Aristotle, despite his evolutionistic notions, does not take the view of a thoroughgoing evolutionist as regards the universe; nor do the Neoplatonists, whose highest principle remains wholly unchanged, though all things emanate from it.

2. Medieval Views

The idea of evolution was not particularly dominant in patristic and scholastic theology and philosophy, both on account of the dualism which runs through them as an echo of Plato and Aristotle, and on account of the generally accepted Christian theory of creation. However, evolution is not generally denied; and with Augustine (De civitate dei, xv. 1) it is taken as the basis for a philosophy of history. Erigena and some of his followers seem to teach a sort of evolution. The issue of finite beings from God is called analysis or resolution in contrast to the reverse ordeification the return to God, who once more assimilates all things. God himself, although denominated the beginning, middle, and end, all in all remains unmixed in his own essence, transcendent though immanent in the world. The teaching of. Nicholas of Cusa is similar to Erigena's, though a certain amount of Pythagoreanism comes in here. The world exhibits explicitly what the Godhead implicitly contains; the world is an animated, ordered whole, in which God is everywhere present. Since God embraces all things in himself, he unites all opposites: he is thecomplicatio omnium contradictoriorum. The idea of evolution thus appears in Nicholas in a rather pantheistic form, but it is not developed.

In spite of some obscurities in his conception of the world Giordano Bruno is a little clearer. According to him God is the immanent first cause in the universe; there is no difference between matter and form; matter, which includes in itself forms and ends, is the source of all becoming and of all actuality. The infinite ether which fills infinite space conceals within itself the nucleus of all things, and they proceed from it according to determinate laws, yet in a teleological manner. Thus the worlds originate not by an arbitrary act, but by an inner necessity of the divine nature. They arenatura naturata, as distinguished from the operative nature of God, natitra naturans, which is present in all thin-S as the being- of all that is, the beauty of all that is fair. As in the Stoic teaching, with which Bruno's philosophy has much in common, the conception of evolution comes out clearly both for physics and metaphysics.