> Humans are built to thrive in danger, chaos and instability. I think a good chunk of humans go insane in a safe and stable environment and resent the things that allow them to live mundane, safe lives -- technology, medicine and rational thinking.
No, I don't think that's true. Humans are built to learn from experience, and one thing that vaccines do is eliminate the experiences that justify their use. That also makes the experience/knowledge of smaller dangers more prominent. For instance, a kid getting his arm paralyzed from the (now discontinued) live oral polio vaccine, looks a lot different if people are commonly getting worse paralysis from wild polio than if no one is getting wild polio at all anymore.
The other thing you should probably take into account when regarding a book from 1929, is the experiences people had back then with (often dangerous) quack cures promising miracles. For instance (https://en.wikipedia.org/wiki/History_of_the_Food_and_Drug_A...):
> By the 1930s, muckraking journalists, consumer protection organizations, and federal regulators began mounting a campaign for stronger regulatory authority by publicizing a list of injurious products which had been ruled permissible under the 1906 law, including radioactive beverages, the mascara Lash lure, which caused blindness, and worthless "cures" for diabetes and tuberculosis. The resulting proposed law was unable to get through Congress for five years, but was rapidly enacted into law following the public outcry over the 1937 Elixir Sulfanilamide tragedy, in which over 100 people died after using a drug formulated with a toxic, untested solvent.