One of the clear implications of the eugenicist mindset was that there were certain humans who were not really humans. It was not common to hear this directly put, although in many cases they come very close. It is important to realize that they did not think they were being prejudicial, but rather, scientific. After all, it wasn’t for no reason that Charles Darwin had originally named his book, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. In the excerpt below, the eugenicist doesn’t mind being explicit.
W. Duncan McKim, Heredity and Human Progress, 1900. pgs 7-8.
To the influences which move the average man to repentance and uplift him to higher endeavor, the low-grade “defective,” whether weakling or habitual criminal, is organically deaf and blind, and that within him which should be a warm and sympathetic human heart is usually, through the unalterable structure of his being, senseless as stone. It is not true that what man has been t his defective creature may be. The laws of his existence and development are very different from those of the “normal” man and this fact must have constant recognition in the practice of our philanthropy. We must distinguish two human types: one characterized by intellectual apathy or complete imbecility, feebleness or absence of moral sense, indolence, lack of self-restraint, and intensity of brutal desires; the other, by intelligence, sensitive conscience, energy, self-control, and capacity for love and self-sacrifice. These types often blend, but our knowledge of defective man has so broadened and deepened, within the recent ears, that we are now in a position to discriminate, with a fair degree of precision, between the individuals who are susceptible to the ordinary influences of incentive and restraint and those whom, for practical purpose, we must regard as outside the pale of society.
It is not the mere wearing of a human form which truly indicates a man. The idiot and the low-grade imbecile are not true men, for certain essential human elements have never entered into them, and never can; nor is the moral idiot truly a man, nor, while the sad condition lasts, the lunatic. These beings live among us as men, but if we reckon with them as human we shall fare much as if we bargained with the dead or with beasts of prey. It is a most depressing revelation that there are beings of like form with ourselves whom we can never treat as brothers, against whom, for our very life, we must exercise perpetual vigilance; but such being the fact, it behooves us, not only for our own safety but for that of our posterity, to adjust ourselves speedily to this knowledge.