given, that the comparatively equal head growth of all known men is no evidence whatever against the theory of their evolutionary descent, while the closely related fact that man shares with certain lower species of animals built like himself a brain development peculiar to him and them, and which has succeeded to an arrested head growth in his and their case alike, is more than an indication, it is very good proof so far as it goes that he and they had a similar if not the same origin and are members of the same family. And it is also evident, in the case of man at least, that this convolutional brain development is continuous from the lowest savages up to the age of machinery and the extreme division of labor, the accompanying institution of voluntary benevolent associations, and the modern forms of parental government, when it thus meets for the first time with a threatened reversal in the case of the routine laborer. He finds himself as a result of these changes in this predicament, he is still in possession, by inheritance, of the full brain development of the civilized, but with less use for, or need of it than has the hunting savage of the neolithic period.
In taking leave of this subject, one question not quite pertinent to the issue can not be repressed. Since all civilizations thus far have encountered a brood of incidental evils peculiarly their own, and, if not of their own creation, still consequent upon them, who can say that the one just exposed may not be the primal cause of the world-wide unrest of the present laboring classes, finding expression in all sorts of disorder from strikes to anarchy—the first fruits of atrophy—the vain attempt to employ an otherwise idle and already degenerating organ of thought, and, like all readjustments to a lower plane, resulting in vicious and reactionary conduct? If this result had been foreseen, could the cause have been suppressed? Is social growth, to any greater extent than individual, modified by desire and volition?