This excerpt from the textbook used in the schools of Tennessee at the time of the trial is pretty wild to read in 2024. And it is important to remember that progressives held many of these views at the time.
Evolution of Man. – Undoubtedly there once lived upon the earth races of men who were much lower in their mental organization than the present inhabitants. If we follow the early history of man upon the earth, we find that at first he must have been little better than one of the lower animals. He was a nomad, wandering from place to place, feeding upon whatever living things he could kill with his hands. Gradually he must have learned to use weapons, and thus kill his prey, first using rough stone implements for this purpose. As man became more civilized, implements of bronze and of iron were used. About this time the subjugation and domestication of animals began to take place. Man then began to cultivate the fields, and to have a fixed place of abode other than a cave. The beginnings of civilization were long ago, but even to-day the earth is not entirely civilized.
The Races of Man. – At the present time there exist upon the earth five races or varieties of man, each very different from the other in instincts, social customs, and, to an extent, in structure. These are the Ethiopian or negro type, originating in Africa; the Malay or brown race, from the islands of the Pacific; the American Indian; the Mongolian or yellow race, including the natives of China, Japan, and the Eskimos; and finally, the highest type of all, the Caucasians, represented by the civilized white inhabitants of Europe and America. ...
Improvement of Man. – If the stock of domesticated animals can be improved, it is not unfair to ask if the health and vigor of the future generations of men and women on the earth might not be improved by applying to them the laws of selection. This improvement of the future race has a number of factors in which we as individuals may play a part. These are personal hygiene, selection of healthy mates, and the betterment of the environment.
Eugenics. – When people marry there are certain things that the individual as well as the race should demand. The most important of these is freedom from germ diseases which might be handed down to the offspring. Tuberculosis, syphilis, that dread disease which cripples and kills hundreds of thousands of innocent children, epilepsy, and feeble-mindedness are handicaps which it is not only unfair but criminal to hand down to posterity. The science of being well born is called eugenics. ...
Parasitism and its Cost to Society. – Hundreds of families such as those described above exist today, spreading disease, immorality, and crime to all parts of this country. The cost to society of such families is very severe. Just as certain animals or plants become parasitic on other plants or animals, these families have become parasitic on society. They not only do harm to others by corrupting, stealing, or spreading disease, but they are actually protected and cared for by the state out of public money. Largely for them the poorhouse and the asylum exist. They take from society, but they give nothing in return. They are true parasites.
The Remedy. – If such people were lower animals, we would probably kill them off to prevent them from spreading. Humanity will not allow this, but we do have the remedy of separating the sexes in asylums or other places and in various ways preventing intermarriage and the possibilities of perpetuating such a low and degenerate race. Remedies of this sort have been tried successfully in Europe and are now meeting with some success in this country.
One is left wondering why we often hear about the abhorrent views of Nazi Germany but rarely hear what was taught in government schools many years before WW2. This history has been largely white washed from our culture. The ideas of Eugenics have been rejected thankfully but we should not forget how in the past many of the elite and intellectuals espoused such ideas. Its an important reminder that while science is a beautiful system for understanding our world it does not provide a moral framework for mankind.

Footnotes

It's worth remembering that "trusting the experts" and "following the science" required one to be an avid supporter of eugenics at one point.
Enter my favorite scene from It's Always Sunny https://www.youtube.com/watch?v=Zgk8UdV7GQ0
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Epistemic humility is too much to ask from our intellectual superiors
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The two big medical ones that come to mind for me are bloodletting and lobotomy. I think people don't really get the issue though. The issue is as you say, trusting the experts without question. Not that someone got something wrong in the past. That will always be true. But questioning the orthodoxy of science and really society is opposed with great prejudice. I get it to some extent. There are many simple minded people that are easily duped. But they are easily duped by scam artists and people that are just arrogantly wrong.
Let the best ideas win.
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I'd put it this way: It's fine to trust experts, but it's stupid to hold a differing view in contempt when you understand neither the official position nor the dissenting one.
None of us have time to learn everything, so we rely on heuristics. If your heuristic is to just trust the official position, that's fine, but have some humility about it.
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Yeah, that's good.
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