Ludwig Wittgenstein, after finishing Tractatus Logico-Philosophicus, went to teach elementary school for six years in rural Austria. Perhaps he thought he could put his philosophy into practice in a sense, and teach children in a new a creative way. However he quickly became disillusioned and wrote to Bertrand Russell:

I know human beings on the average are not worth much anywhere, but here they are much more good-for-nothing and irresponsible than elsewhere.

Apparently he was very demanding, and tried to teach the children math and logic that was quite advanced, and when students got the answer wrong he would administer corporal punishment (not uncommon to the time). Sometimes this went very far, however, and he even knocked an 11 year old boy unconscious, and went to trial.

Wittgenstein was, shall we say, a rather intense individual.