[[p. 103]] Sir,--In the last number of your periodical, Dr. Hunt's paper "On the Application of the Principle of Natural Selection to Anthropology," which was read at Nottingham, is printed at length. I beg, therefore, a little of your space to reply to the charge of being entirely "illogical," in the application which I have elsewhere made of the principle of natural selection to the question of the origin of man.

    Dr. Hunt selects from my paper "On the Origin of Human Races, etc., deduced from the Theory of Natural Section," published in the Review of May, 1864, two statements of opinion which are not, perhaps, very important parts of that paper, and maintains that they are not fairly deducible from Mr. Darwin's principles. The first is, "Man may have been, indeed I believe must have been, once a homogeneous race." The second is that, "Man may and probably will in the future again become a single homogeneous race." I am only now concerned to show, that admitting the application of "Natural Selection" to man, these are fair and logical inferences.

    In Chapter IV. of The Origin of Species, Mr. Darwin maintains, that just as all varieties of a species are descended from one homogeneous species, so all the species of a genus are descended from one parent species, and all the genera of a family from one parent genus; and generally any group of animals, whether large or small, has descended from a more or less remote single species. It matters not, therefore, whether man be a species with many varieties, or a genus with many species, in either case he has, on Mr. Darwin's principles, descended from one species, and if that one species was sub-divided into varieties, then by going a little further back we arrive at their common ancestor in a single homogeneous species, or one in which there are no well marked and permanent varieties. Such species among animals, when we now find them, are almost always confined to a limited area, cosmopolitan species being as a rule variable. I think, therefore, that when I state that I believe man was once "a single homogeneous race," I am merely stating a truism to those who admit the application to him of the principle of "natural selection."

    It is, however, my second statement, that man may in the future again become a single homogeneous race, that seems so paradoxical to Dr. Hunt; and no doubt it is very like blowing hot and cold with the same mouth to make "natural selection" answerable for such opposite [[p. 104]] results. But the whole scope and purport of my paper was to show, that since that early period at which the ancestors of mankind formed a single homogeneous race, all the very distinct forms now existing (and perhaps others now extinct) were produced by "natural selection," till the process was checked by the development of the mind of man, causing changes of his external form to be less important than advances in his intellectual and moral nature. Had this check not occurred it seems to me probable that the world would now be inhabited by many quite distinct species, and, perhaps, even distinct genera of the animal man. As it is, the forms of man on the earth are steadily decreasing in number, owing to the more rapid mental, moral, and physical development of a few superior races. It is a bare fact that man is becoming more homogeneous. The most extreme forms, the native American, the New Zealander, the Australian, and the Polynesian races, are all doomed. It is a mere question of time as to when these will become extinct. And when I see how Europeans have spread over tropical South America, when I contemplate the rapid increase of that energetic race which in three centuries has changed the vast continent of North America from a waste of forest to a hive of industry and high civilisation, when I think of the possible advances of science in making the forces of nature subserve the wants and supplement the energies of this dominant race, I cannot believe that the resistance of lower races and lower civilisations will permanently avail them, or that climatal influences will for ever prevent the tropics from being the home of the civilised man armed with ever-increasing insight into nature and nature's laws.

    This is the "struggle for existence" on the grandest scale; and I believe the next few centuries will see it go on at such a rate that even the great races hitherto dominant in their own areas--the Negroes, the Hindoos, and the Mongols--will begin to suffer from it. I cannot believe that the progress of civilisation and science will stop, and I can see no end to such progress, but the absorption and displacement of lower races by higher, till the world again become inhabited by a "homogeneous race," whose command over nature and whose powers of intercommunication will be such as to prevent local conditions affecting, to more than a very slight degree, its external characteristics. The globe is or very soon will be to civilised man, an area over which he can roam at will, with as much ease as any animal over the single island or continental area that it inhabits; and it will then become impossible for an inferior race long to maintain itself against him. If then we admit that the mental are more important than the more corporeal forces in the great human "struggle for existence," it is a necessary result that the higher will continue to [[p. 105]] displace or absorb the lower races of man. It is for those who deny this to show why and when this process will cease.

    I believe that I have now shown that the principles of Mr. Darwin's Origin of Species, if applied to man with such modifications as are required by the great development and vast importance of his intellectual and moral rather than his mere animal nature, leads to the apparently paradoxical result that he is tending to become again as his progenitors once undoubtedly must have been, "a single homogeneous race."