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embryo or principium. Plato's world was a 'zoon,' a living thing, a natural production.”

Furthermore, to the ancient writers of the Bible the idea of origin by birth from some antecedent form— and this is the essential idea of evolution-was perfectly natural. They speak of the "generations of the heavens and the earth" as of the "generations" of the patriarchs. The first book of the Bible is still called Genesis, the book of births. The writer of the ninetieth Psalm says, "Before the mountains were born, or ever thou hadst brought to birth the earth and the world." And what satisfactory meaning can you give to the words, "Let the earth bring forth," and "the earth brought forth," in immediate proximity to the words, "and God made," unless while the ultimate source was God's creative power, the immediate process of formation was one of evolution.

The Bible is big and broad enough to include both ideas, the human mind is prone to overestimate the one or the other. Traces, at least, of a similar mode of thought persisted by the Greek Fathers of the Church, and disappeared, if ever, with the predominance of Latin theology. To the oriental the idea of evolution is natural. The earth is to him no inert, resistant clod; she brings forth of herself.

But our ancestors lived on a barren soil beneath a forbidding sky. They were frozen in winter and parched in summer. Nature was to them no kind fostermother, but a cruel stepmother, training them by stern discipline to battle with her and the world. They peopled the earth with gnomes and cobolds and giants, and their nymphs were the Valkyre. Their God was Thor, of the thunderbolt and hammer, and who

yet lived in continual dread of the hostile powers of Nature. A Norse prophet or prophetess standing beside Elijah at Horeb would have bowed down before the earthquake or the fire; the oriental waited for the "still small voice." And we are heirs to a Latin theology grafted on to the Thor-worship of our pagan ancestors. The idea of a Nature producing beneficently and kindly at the word of a loving God is foreign to all our inherited modes of thought. And our views of the heart of Nature are about as correct as those of our ancestors were of God. A little more of oriental tendencies of thought would harm neither our theology nor our life.

What, then, is the biblical idea of Nature? God speaks to the earth, in the first chapter of Genesis, and the earth responds by "giving birth" to mountains and living beings. It is evidently no mere lifeless, inert clod, but pulsating with life and responsive to the divine commands. While yet a chaos it had been brooded over by the Divine Spirit. It is like the great "wheels within wheels," with rings full of eyes round about, which Ezekiel saw in his vision by the river Chebar. "When the living creatures went, the wheels went by them; and when the living creatures were lifted up from the earth, the wheels were lifted up. Whithersoever the spirit was to go, they went, thither was their spirit to go; and the wheels were lifted up over against them for the spirit of the living creatures (or of life) was in the wheels." And above the living creatures was the firmament and the throne of God. So Nature may be material, but it is material interpenetrated by the divine; if you call it a fabric, the woof may be material but the warp is God. This view contains all

the truth of materialism and pantheism, and vastly more than they, and it avoids their errors and omissions.

To the old metaphysical hypothesis of evolution Mr. Darwin gave a scientific basis. It had always been admitted that species were capable of slight variation and that this divergence might become hereditary and thus perhaps give rise to a variety of the parent species. But it was denied that the variation could go on increasing indefinitely, it seemed soon to reach a limit and stop. Early in the present century Lamarck had attempted to prove that by the use and disuse of organs through a series of generations a great divergence might arise resulting in new species. But the theory was crude, capable at best of but limited application, and fell before the arguments and authority of Cuvier. The times were not ripe for such a theory. Some fifty years later, Mr. Darwin called attention to the struggle for existence as a means of aggregating these slight modifications in a divergence sufficient to produce new species, genera, or families. His argument may be very briefly stated as follows:

1. There is in Nature a law of heredity; like begets like.

2. The offspring is never exactly like the parent; and the members of the second generation differ more or less from one another. This is especially noticeable in domesticated plants and animals, but no less true of wild forms. If the parent is not exactly like the other members of the species, some of its descendants will inherit its peculiarities enhanced, others diminished.

3. Every species tends to increase in geometrical

progression. But most species actually increase in number very slowly, if at all. Now and then some insect or weed escapes from its enemies, comes under favorable food conditions, and multiplies with such rapidity that it threatens to ravage the country. But as it multiplies it furnishes an abundance of food for the enemies which devour it, or of food and place for the parasites in and upon it; and they increase with at least equal rapidity. Hence while the vanguard increases prodigiously in numbers, because it has outrun these enemies, the rear is continually slaughtered. And thus these plagues seem in successive generations to march across the continent.

And yet even they give but a faint idea of the reproductive powers of plants and animals. The female fish produces often many thousands, sometimes hundreds of thousands of eggs. Insects generally from a hundred to a thousand. Even birds, slowly as they increase, produce in a lifetime probably at least from twelve to twenty eggs. Now let us suppose that all these eggs developed, and all the birds lived out their normal period of life, and reproduced at the same rate. After not many centuries there would not be standing room on the globe for the descendants of a single pair.

Again, of the one hundred eggs of an insect let us suppose that only sixty develop into the first larval, caterpillar, stage. Of these sixty, the number of members of the species remaining constant, only two will survive. The other fifty-eight die of starvation, parasites, or other enemies, or from inclement weather. Now which two of all shall survive? Those naturally best able to escape their enemies or to resist unfavorable influences; in a word, those best suited to their

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conditions, or, to use Mr. Darwin's words, "conformed to their environment."

Now if any individual has varied so as to possess some peculiarity which enables it even in slight degree to better escape its enemies or to resist unfavorable conditions, those of its descendants who inherit most markedly this peculiar quality or variation will be the most likely to escape, those without it to perish. If a form varies unfavorably, becomes for instance more conspicuous to its enemies, it will almost certainly perish. Thus favorable variations tend to increase and become more marked from generation to generation.

Now it has always been known that breeders could produce a race of markedly peculiar form or characteristics by selecting the individuals possessing this quality in the highest degree and breeding only from these. The breeder depends upon heredity, variation, and his selection of the individuals from which to breed. Similarly in nature new species have arisen through heredity, variation, and a selection according to the laws of nature of those varying in conformity with their environment. And this Mr. Darwin called natural, in contrast with the breeder's artificial, "selection," arising from the "struggle for existence," and resulting in what Mr. Spencer has called the "survival of the fittest."

Let us take a single illustration. Many of the species of beetles on oceanic islands have very rudimentary wings, or none at all, and yet their nearest relatives are winged forms on some neighboring continent. Mr. Darwin would explain the origin of these evidently distinct wingless species as follows: They are descended from winged ancestors blown or otherwise

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