new, we may safely reply in the negative. The change we have supposed is fortunately incapable of being effected, otherwise the attempt would doubtless be made in the name of "progress."
But we may follow the principle of differentiation, and trace its workings over the boundaries of biology into those of sociology, if such a science can be said to exist. Where differences of structure can no longer be traced we still find differences of function. In man we find no variation in the number and position of bodily organs; yet identical organs in different individuals are trained to special tasks which to other men would be impossible, and which might seem to necessitate a structural difference. We come, that is to say, upon the division of labor, which is one of the most characteristic and essential features of civilization. We have seen that in the lowest forms of animal life the entire body seemed to subserve every vital process; just so in the lowest stages of human society, every individual is at once warrior, hunter, builder, maker of arms and other utensils, and—in as far as agriculture is practised at all—tiller of the soil. Every man is perforce, in the words of the adage, "Jack of all trades," with the inevitable consequence that he is "master of none." In a civilized nation, just as in the higher animals, all this is reversed. Every function has its special organ, or, in other words, every task is committed to a separate man or body of men. In all this we can trace out nothing that speaks of arbitrary interference or compulsion. In the animal or human body each function is committed to organs fitted for that function. The stomach does not protest because it is not the seat of respiration, nor does the heart crave to undertake the task of digestion, either instead of or along with its own duties. In human society—complain as we may about "square pegs" being placed in "round holes"—the different tasks are in the main assigned to the men most competent for their performance. In a savage tribe the strongest and bravest naturally leads in war; the man keenest of eye and ear becomes the scout, either as regards hostile tribes or beasts of the chase. The wisest and most eloquent—attributes which, if necessarily connected in primitive times, are now so no longer—took the foremost place in council. The man of greatest manual dexterity would be chief bow-maker to the tribe. The process in operation was, in fact, natural selection. The man who undertook a task for which he was unfitted, or less fitted than others, was gradually eliminated, as far as that particular task was concerned. In proportion as new wants sprung up and new means of gratifying them were devised, social functions were multiplied, and the division of labor became more minute. Yet even in the very rudest state, as far at least as anthropologists have been able to trace, there never was a time when the duties of all persons were absolutely identical. To men and to women different duties were assigned on the same principle of natural selection. Changes have, indeed, taken place in the distribution of the tasks respectively allotted to the two sexes. But these changes,