As for the War and Peace example, probably social concerns can never be completely be separated from medicine per se, although of course Tolstoy’s example is to the extreme. The overt point there is of course that Natacha’s “illness” makes it possible to save face in the social scandal. Good that the doctors could be of help to the Rostovs in also that. But bacteria in drinking water that kill babies is a bit different matter.

Incidentally, I’ve read that Charles Dickens’s novels contain detailed descriptions of what are now recognized as various medical disorders, long before they were known to be medical problems. For example, a character in “The Pickwick Papers” exhibits textbook symptoms of severe sleep apnea, and one in “Bleak House” has dyslexia.

You don’t have to be a medical expert to know that all else equal, new evidence that increases P(A|~B) (in this case, the use of medical treatment even when it won’t work, on account of the impulse to “do something” and make people feel taken care of), should increase P(~B|A).

The discovery of additional motives for medicine (aside from curing someone directly) should lower our confidence that any actually applied medical procedure works.