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.