Carl Jung? Sigmund Freud? Guy Bellamy? Jolande Jacobi? Apocryphal?
Show me a sane man and I will cure him for you.
The best citation I have found appeared in a newspaper article in 1975. The words were attributed to Jung, but this date is fourteen years after his death. So I am handing this task off to you, if you chose to accept it. This is a somewhat extreme statement with a humorous edge; hence, it probably did not appear in a monograph or journal article.
Quote Investigator: There is evidence that Jung made a remark of this type. The English author Vincent Brome has written a large number of biographies including some about individuals in Sigmund Freud’s circle. In 1978 he published a volume about Jung that included information from an interview with Jolande Jacobi, a long-time assistant to the psychiatrist. Jung died in 1961, and the interview was conducted in 1963 according to Brome. Here is an excerpt describing Jung from the biography together with a footnote [JJCJ]:
It was the explosive person who said one day to his wife, ‘If I get another perfectly normal adult malingering as a sick patient I’ll have him certified!’ And to George Beckwith, his American friend, ‘I’m sometimes driven to the conclusion that boring people need treatment more urgently than mad people.’ Witty on some occasions, he commented to one of his assistants, ‘Show me a sane person and I’ll cure him for you.’ [Footnote 1]
[Footnote 1 for Chapter 23] Jolande Jacobi, author’s interview, 24 Nov 1963.
Here are additional selected citations in chronological order.