"When the Freuds entertained in Vienna they always met people with a joke."
Sigmund Freud
Public DomainSigmund Freud
Like Julia, most people don't associate Sigmund Freud, the Viennese psychiatrist famous for his theories about the unconscious mind (and especially the sex drive), with jokes. But in 1905 he published a book entitled "Jokes and their Relation to the Unconscious", explaining his theory that jokes allow people to express forbidden ideas, which releases emotion.

Whether he was actually funny to be around is, of course, another matter.

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