"Vapours" actually were a major thing in medical research once, cured by bloodletting and mercury IIRC.
There are all sort of models still widely believed today. Some are unassailable (evolution, germ theory), some seem right more often than not ("don't eat bacon"), and some seem so right but nothing based on them works ("cholesterol is bad").
So this sort of naive belief in our ability to model the processes in a body or a cell has out of fashion at least since WW2. It's still used to come up with ideas to try. But even there, purely random exploration of the search space is not consistently worse.
There are all sort of models still widely believed today. Some are unassailable (evolution, germ theory), some seem right more often than not ("don't eat bacon"), and some seem so right but nothing based on them works ("cholesterol is bad").
So this sort of naive belief in our ability to model the processes in a body or a cell has out of fashion at least since WW2. It's still used to come up with ideas to try. But even there, purely random exploration of the search space is not consistently worse.