Think of it. For countless ages, millions upon millions of years, we see the earth swarming with life, low bestial life, devouring and devoured, myriads of forms, all in bondage to nature or natural forces, living only to eat and to breed, localized, dependent upon place and clime, shaped to specific ends like machines,—to fly, to swim, to climb, to run, to dig, to drill, to weave, to wade, to graze, to crush,—knowing not what they do, as void of conscious purpose as the thorns, the stings, the hooks, the coils, and the wings in the vegetable world, making no impression upon the face of nature, as much a part of it as the trees and the stones, species after species having its day, and then passing off the stage, when suddenly, in the day before yesterday in the geologic year, so suddenly as to give some color of truth to the special creation theory, a new and strange animal appears, with new and strange powers, separated from the others by what appears an impassable gulf, less specialized in his bodily powers than the others, but vastly more specialized in his brain and mental powers, instituting a new order of things upon the earth, the face of which he in time changes through his new gift of reason, inventing tools and weapons and language, harnessing the physical forces to his own ends, and putting all things under his feet,—man the wonder-worker, the beholder of the stars, the critic and spectator of creation itself, the thinker of the thoughts of God, the worshiper, the devotee, the hero, spreading rapidly over the earth, and developing with prodigious strides when once fairly launched upon his career. Can it be possible, we ask, that this god was fathered by the low bestial orders below him,—instinct giving birth to reason, animal ferocity developing into human benevolence, the slums of nature sending forth the ruler of the earth. It is a hard proposition, I say, undoubtedly the hardest that science has ever confronted us with.
Haeckel, discussing this subject, suggests that it is the parvenu in us that is reluctant to own our lowly progenitors, the pride of family and position, like that of would-be aristocratic sons who conceal the humble origin of their parents. But it is more than that; it is the old difficulty of walking by faith where there is nothing visible to walk upon: we lack faith in the efficiency of the biologic laws, or any mundane forces, to bridge the tremendous chasm that separates man from even the highest of the lower orders. His radical unlikeness to all the forms below him, as if he moved in a world apart, into which they could never enter, as in a sense he does, is where the difficulty lies. Moreover, evolution balks us because of the inconceivable stretch of time during which it has been at work. It is as impossible for us to grasp geological time as sidereal space. All the standards of measurement furnished us by experience are as inadequate as is a child's cup to measure the ocean.
Several million years, or one million years,—how can we take it in? We cannot. A hundred years is a long time in human history, and how we pause before a thousand! Then think of ten thousand, of fifty thousand, of one hundred thousand, of ten hundred thousand, or one million, or of one hundred million! What might not the slow but ceaseless creative energy do in that time, changing but a hair in each generation! If our millionaires had to earn their wealth cent by cent, and carry each cent home with them at night, it would be some years before they became millionaires. This is but a faint symbol of the slow process by which nature has piled up her riches. She has had no visions of sudden wealth. To clothe the earth with soil made from the disintegrated mountains—can we figure that time to ourselves? The Orientals try to get a hint of eternity by saying that when the Himalayas have been ground to powder by allowing a gauze veil to float against them once in a thousand years, eternity will only have just begun. Our mountains have been pulverized by a process almost as slow. In our case the gauze veil is the air, and the rains, and the snows, before which even granite crumbles. See what the god of erosion, in the shape of water, has done in the river valleys and gorges—cut a mile deep in the Colorado canyon, and yet this canyon is but of yesterday in geologic time. Only give the evolutionary god time enough and all these miracles are surely wrought.
Truly it is hard for us to realize what a part time has played in the earth's history,—just time, duration,—so slowly, oh, so slowly, have the great changes been brought about! The turning of mud and silt into rock in the bottom of the old seas seems to have been merely a question of time. Mud does not become rock in man's time, nor vegetable matter become coal. These processes are too slow for us. The flexing and folding of the rocky strata, miles deep, under an even pressure, is only a question of time. Allow time enough and force enough, and a layer of granite may be bent like a bow. The crystals of the rock seem to adjust themselves to the strain, and to take up new positions, just as they do, much more rapidly, in a cake of ice under pressure. Probably no human agency could flex a stratum of rock, because there is not time enough, even if there were power enough. "A low temperature acting gradually," says my geology, "during an indefinite age would produce results that could not be otherwise brought about even through greater heat." "Give us time," say the great mechanical forces, "and we will show you the immobile rocks and your rigid mountain chains as flexible as a piece of leather." "Give us time," say the dews and the rains and the snowflakes, "and we will make you a garden out of those same stubborn rocks and frowning ledges." "Give us time," says Life, starting with her protozoans in the old Cambrian seas, "and I will not stop till I have peopled the earth with myriad forms and crowned them all with man."
Dana thinks that had "a man been living during the changes that produced the coal, he would not have suspected their progress," so slow and quiet were they. It is probable that parts of our own sea-coast are sinking and other parts rising as rapidly as the oscillation of the land and sea went on that resulted in the laying down of the coal measures.
An eternity to man is but a day in the cosmic process. In the face of geologic time, man's appearance upon the earth as man, with a written history, is something that has just happened; it was in this morning's paper, we read of it at breakfast. As evolution goes, it will not be old news yet for a hundred thousand years or so, and by that time, what will he have done, if he goes on at his present rate of accelerated speed? Probably he will not have caught the gods of evolution at their work, or witnessed the origin of species by natural descent, these things are too slow for him; but he will certainly have found out many things that we are all eager to know.
In nature as a whole we see results and not processes. We see the rock strata bent and folded, we see the whole mountain-chains flexed and shortened by the flexure; but had we been present, we should not have suspected what was going on. Our little span of life does not give us the parallax necessary. The rock strata, miles thick, may be being flexed now under our feet, and we know it not. The earth is shrinking, but so slowly! When, under the slow strain, the strata suddenly give way or sink, and an earthquake results, then we know something has happened.
A recent biologist and physicist thinks, and doubtless thinks wisely, that the reason why we have never been able to produce living from non-living matter in our laboratories, is that we cannot take time enough. Even if we could bring about the conditions of the early geologic ages in which life had its dawn, which of course we cannot, we could not produce life because we have not geologic time at our disposal.
The reaction which we call life was probably as much a cosmic or geologic event as were the reactions which produced the different elements and compounds, and demanded the same slow gestation in the womb of time. During what cycles upon cycles the great mother-forces of the universe must have brooded over the inorganic before the organic was brought forth! The archean age, during which the brooding seems to have gone on, was probably as long as all the ages since.
How we are baffled when we talk about the beginning of anything in nature or in our own lives! In our experience there must be a first, but when did manhood begin; when did puberty, when did old age, begin? When did each stage of our mental growth begin? When or where did the English language begin, or the French, or the German? Was there a first English word spoken? From the first animal sound, if we can conceive of such, up to the human speech of to-day, there is an infinite gradation of sounds and words.