There is the story from antiquity about the dangerous rocks near the edge of the world that moved back and forth, and would break any ship attempting passage. When the explorers saw them for the first time, they stopped moving.
There is much in that, if you can avoid the melodramatic or pop-psychiatry reading. Thoughts can change the way things are.
I recall, at Indiana, in the first year of law studies (before a Torts professor decided to give me the lowest score in the section on an ambiguous rubric, taking me from near the top to Midwestern median), the temperature control in the rooms at the beginning of the semester was a bit off, so the rooms were sauna-like for weeks. Finally, I ordered a digital thermometer on Amazon, and the day that I brought it in in my bag, the room temperature was normal, and it stayed that way. Coincidence, undoubtedly, but it does highlight the fact that as much as we might think ourselves sufficiently well-informed, and sort of sitting back and watching the orrery or the diorama of things, life is basically an ascending rocket (screaming across the sky) of untrammeled intuition, and its best to be looking out the window of your rocket (or monad), with the furious influx of knowledge of how things are
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If a society, seeking to make all things new, builds an industrial mechanism to assure the prosperity of a healthy preponderance of the population, and a sufficient number from among that preponderance (and for whom it is an active and present question) take the view that the poor people should be done away with, this is arguably some indication of a persistent issue within the species, and one that perhaps should be remembered the next time folks set about to make all things new..