It is true that science has not discovered, and perhaps never will discover, what physical differences correspond to the differences in individual minds. Phrenology, starting with brilliant promises, and bringing to the task powers of no mean order, has failed. But there is a vast difference between the characteristics by which we distinguish individuals of the same race, and those by which we distinguish races themselves. The former are not strictly--at least not immediately--hereditary, for the child most often differs from both parents in body and mind, because no two individuals, as no two leaves of one tree, are precisely alike. But, although every oak-leaf differs from its fellow, we know the leaf of the oak-tree from that of the beech, or every other; and, in the same manner, races are distinguished by peculiarities which are hereditary and permanent. Thus, every negro differs from every other negro, else we could not tell them apart; yet all, if pure blood, have the same characteristics in common that distinguish them from the white. I have been prolix, but intentionally so, in my discrimination between individual distinction and those of race, because of the latter, comparative anatomy takes cognizance; the former are left to phrenology, and I wished to remove any suspicion that in the investigation of moral and intellectual diversities of races, recourse must be had to the ill-authenticated speculations of a dubious science. But, from the data of comparative anatomy, attained by a slow and cautious progress, we deduce that races are distinguished by certain permanent physical characteristics; and, if these physical characteristics correspond to the mental, it follows as an obvious conclusion that the latter are permanent also. History ratifies the conclusion, and the common sense of mankind practically acquiesces in it. To return, then, to our author. I would add to his two elements of civilization a third--intellect _per se_; or rather, to speak more correctly, I would subdivide one of his elements into two, of which one is probably dependent on physical conformation. The combinations will then be more complex, but will remove every difficulty. I remarked that although we may consider all races as possessed of equal moral endowments, we yet may speak of moral diversities; because, without the light of revelation, man has nothing but his intellect whereby to compass the immaterial world, and the manifestation of his moral faculties must therefore be in proportion to the clearness of his intellectual, and their preponderance over the animal tendencies. The three I consider as existing about in the following relative proportions in the three great groups under which Mr. Gobineau and Mr. Latham[28] have arranged the various races--a classification, however, which, as I already observed, I cannot entirely approve.