It's from 1961 actually.
"What Jimmy didn't know was that Ralph was sick -- a sickness that was not visible like smallpox, but no less dangerous and contagious--a sickness of the mind."
Brilliant. The next time an odd-looking man offers me a lift home, takes me fishing and shows me gay porn, I'll be sure to tell my parents right away. Even if his "off-colour jokes" make me feel like a man.