By the 18th century people were way past that. It's an interesting mix; they knew quite a lot about what to do about many things, and were determined to figure stuff out scientifically, but were still stuck with many ancient beliefs like those about bloodletting and purging. And then things actually got worse for a time in the 19th century with the "professionalization" of medicine. Doctors now wanted to be seen as gentlemen, gentlemen never had dirty hands, so doctors refused to wash their hands.

We've still got a lot of superstitions and unscientific practices in medicine these days, too. I wonder what people will be saying about us in a hundred years.