Dr. Ignaz Semmelweis on discovering the effects of washing your hands before operating on patients. Simple, yet highly effective.
Semmelweis is, to me, an interesting story about how it's not all that useful to be right if you're unable to persuade, and Semmelweis' difficulties with persuasion have little to do with his adversaries bloody-mindedness and much to do with his.
EDIT: Joe Rogan Episode #1272 - Lindsey Fitzharris