Men have had the same origin as other animals; they have the same general architecture of body and mind; and they have the same destiny. And they stand on the same general level of ethical claim and obligation.

Man bears in his bodily structure clear traces of his descent from some lower form; but it may be urged that, as man differs so greatly in his mental power from all other animals, there must be some error in this conclusion. No doubt the difference in this respect is enormous, even if we compare the mind of one of the lowest savages, who has no words to express any number higher than four, and who uses no abstract terms for the commonest objects or affections, with that of the most highly organised ape.

Animals are born, are sentient and are mortal. In these things they resemble man. In their superficial anatomy — less in their deep anatomy — in their habits, in their time, in their physical capacities, they differ from man. They are both like and unlike.

Is Man so different from any of these Apes that he must form an order by himself? Or does he differ less from them than they differ from one another, and hence must take his place in the same order with them?

Tis from the resemblance of the external actions of animals to those we ourselves perform, that we judge their internal likewise to resemble ours; and the same principle of reasoning, carry'd one step further, will make us conclude that since our internal actions resemble each other, the causes, from which they are deriv'd, must also be resembling. When any hypothesis, therefore, is advanc'd to explain a mental operation, which is common to men and beasts, we must apply the same hypothesis to both.

We are not just rather like animals; we are animals. Our difference from other species may be striking, but comparisons with them have always been, and must be, crucial to our view of ourselves.

Whatever part of the animal fabric—whatever series of muscles, whatever viscera might be selected for comparison—the result would be the same—the lower Apes and the Gorilla would differ more than the Gorilla and the Man.

'Tis from the resemblance of the external actions of animals to those we ourselves perform, that we judge their internal likewise to resemble ours; and the same principle of reasoning, carry'd one step farther, will make us conclude that since our internal actions resemble each other, the causes, from which they are deriv'd, must also be resembling.

The question of the position of man, as an animal, has given rise to much disputation, with the result of proving that there is no anatomical or developmental character by which he is more widely distinguished from the group of animals most nearly allied to him, than they are from one another.

Kinship is universal. The orders, families, species, and races of the animal kingdom are the branches of a gigantic arbour. Every individual is a cell, every species is a tissue, and every order is an organ in the great surging, suffering, palpitating process. Man is simply one portion of the immense enterprise. He is as veritably an animal as the insect that drinks its little fill from his veins, the ox he goads, or the wild-fox that flees before his bellowings. Man is not a god, nor in any imminent danger of becoming one. He is not a celestial star-babe dropped down among mundane matters for a time and endowed with wing possibilities and the anatomy of a deity. He is a mammal of the order of primates, not so lamentable when we think of the hyena and the serpent, but an exceedingly discouraging vertebrate compared with what he ought to be. He has come up from the worm and the quadruped. His relatives dwell on the prairies and in the fields, forests, and waves. He shares the honours and partakes of the infirmities of all his kindred. He walks on his hind-limbs like the ape; he eats herbage and suckles his young like the ox; he slays his fellows and fills himself with their blood like the crocodile and the tiger; he grows old and dies, and turns to banqueting worms, like all that come from the elemental loins. He cannot exceed the winds like the hound, nor dissolve his image in the mid-day blue like the eagle. He has not the courage of the gorilla, the magnificence of the steed, nor the plaintive innocence of the ring-dove. Poor, pitiful, glory-hunting hideful! Born into a universe which he creates when he comes into it, and clinging, like all his kindred, to a clod that knows him not, he drives on in the preposterous storm of the atoms, as helpless to fashion his fate as the sleet that pelts him, and lost absolutely in the somnambulism of his own being.

The man-like Apes... have certain characters of structure and of distribution in common.

Such close observations of apes and birds and dolphins remind us that humanity is part of a great animal kingdom. All species within this kingdom differ from one another in significant ways, to be sure, but the kingdom does not seem to be organized on the superior/inferior hierarchy. Species are merely different from one another; they are not better than, nor more or less advanced than, each other. The core experience of all animal life is strikingly similar.

man may see a great deal of difference between grass and a little tree, but if you mount very high, the grass and the biggest tree will appear much the same. So, from the standpoint of the highest ideal, the lowest animal and the highest man are the same.

The difference between men is in their principle of association. Some men classify objects by color and size and other accidents of appearance; others by intrinsic likeness, or by the relation of cause and effect. The progress of the intellect is to the clearer vision of causes, which neglects surface differences. To the poet, to the philosopher, to the saint, all things are friendly and sacred, all events profitable, all days holy, all men divine. For the eye is fastened on the life, and slights the circumstance. Every chemical substance, every plant, every animal in its growth, teaches the unity of cause, the variety of appearance.