The exact object at which this leading section of the Essay is aimed is, in the Essayist’s words, this:—“A complete reply to the difficulty which astronomical discoveries appeared to place in the way of religion:—the difficulty of the opinion that Man, occupying this speck of earth but as an atom in the universe, surrounded by millions of other globes larger, and to all appearance nobler, than that which he inhabits, should be the object of the peculiar care and guardianship of the favour and government of the Creator of All, in the way in which religion teaches us that he is.”[16] What is that “complete reply?” The following passage contains a key to the entire speculation of the Essayist, and deserves a thoughtful perusal:— “That the scale of man’s insignificance is _of the same order in reference to time as to space_. That Man—the Human Race from its origin till now—has occupied but an atom of time as he has occupied but an atom of space.”... “If the earth, as the habitation of Man, is a speck in the midst of an infinity of space, the Earth, as the habitation of Man, is also a speck at the end of an infinity of time. If we are as nothing in the surrounding universe, we are as nothing in the elapsed eternity; or rather in the elapsed organic antiquity during which the Earth has existed, and been the abode of life. If Man is but one small family in the midst of innumerable possible households, he is also but one small family, the successor of innumerable tribes of animals, not possible only, but actual. If the planets may be the seats of life, we know that the seas, which have given birth to our mountains, were so. If the stars may have hundreds of systems of tenanted planets rolling round them, we know that the secondary group of rocks does contain hundreds of tenanted beds, witnessing of as many systems of organic creation. If the Nebulæ may be planetary systems in the course of formation, we know that the primary and transition rocks either show us the earth in the course of formation, as the future seat of life, or exhibit such life as already begun. “How far that which Astronomy thus asserts as possible, is probable—what is the value of these possibilities of life in distant regions of the universe, we shall hereafter consider; but in what Geology asserts, the case is clear. It is no possibility, but a certainty. No one will now doubt that shells and skeletons, trunks and leaves, prove animal and vegetable life to have existed. Even, therefore, if Astronomy could demonstrate all that her most fanciful disciples assume, Geology would still have a complete right to claim an equal hearing—to insist on having _her analogies_ regarded. She would have a right to answer the questions of Astronomy, when she asks, How can we believe this? And to have her answer accepted.”[17]