Your "wise man" had syphilis, or so my mother said, but that could have been just Allied propaganda. What is true is that in those days before antibiotics, the late stage caused paresis and sufferers went quite mad. Someone who did die of it was Lord Randolph Churchill, his archenemy's father.
Another thing I have heard is that Hitler loved his amphetamines, had a doctor who used to hit him up every day. So that would hardly make him sane, like ice heads today, nature of the drug is he may have thought he still ruled the world when they were losing WWII. In short, he was mad as a cut snake.
Your choice of hero says a lot about you lot.