In an immense universe, a little globe revolves around a star; it is the third in the row— Mercury, Venus, Earth—of the planetary family. It is of a solid core covered over most of its surface with liquid and it has a gaseous envelope. Living creatures fill the liquid; other living creatures fly in the gas ,and still others creep and walk upon the ground on the bottom of the gaseous ocean.
Man, a being of erect stature, thinks himself the prince of creation. He felt like this long before he, by his own efforts, came to know how to fly on wings of metal around the globe. He felt godlike long before he could talk to his fellow-man on the other side of the globe. Today he can see the microcosm in a drop and the elements in the stars. He knows the laws governing the living cell with its chromosomes, and the laws governing the macrocosm of the sun, moon, planets, and stars. He assumes that gravitation keeps the planetary system together, man and beast on their planet, the sea within its borders.
For millions and millions of years, he maintains, the planets have rolled along on the same paths, and their moons around them, and man in these eons has arisen from a one-cell infusorium all the long way up the ladder to his status of Homo Sapiens. Is man’s knowledge now nearly complete? Are only a few more steps necessary to conquer the universe: to extract the energy of the atom, to cure cancer, to control genetics, to communicate with other planets and learn if they have living creatures, too?
Here begins Homo ignoramus. He does not know what life is or how it came to be and whether it originated from inorganic matter. He does not know whether other planets of this sun or of other suns have life on them, and if they have, whether the forms of life there are like those around us, ourselves included. He does not know how this solar system came into being, although he has built up a few hypotheses about it. He knows only that the solar system was constructed billions of years ago.
He does not know what this mysterious force of gravitation is that holds him and his fellow man on the other side of the planet with their feet on the ground, although he regards the phenomenon itself as “the law of laws.” He does not know what the earth looks like five miles under his feet. He does not know how mountains came into existence or what caused the emergence of the continents, although he builds hypotheses about these, nor does he know from where oil came— again hypotheses.
He does not know why, only a short time ago, a thick glacial sheet pressed upon most of Europe and North America, as he believes it did; nor how palms could grow above the polar circle, nor how it came about that the same fauna fill the inner lakes of the Old and the New World. He does not know where the salt in the sea came from.
Although man knows that he has lived on this planet for millions of years, he finds a recorded history of only a few thousand years. And even these few thousand years are not sufficiently well known. Why did the Bronze Age precede the Iron Age even though iron is more widely distributed over the world and its manufacture is simpler than that of the alloy of copper and tin? By what mechanical means were structures of immense blocks built on the high mountains of the Andes? What caused the legend of the Flood to originate in all the countries of the world? Is there any adequate meaning to the term “antediluvian”? From what experiences grew the eschatological pictures of the end of the world?
Some of these questions may have been answered, but only at the cost of giving up certain notions now regarded as sacred laws in science—the millions of years of the present constitution of the solar system and the harmonious revolution of the earth—with all their implications as regards the theory of evolution.