“[A proverb is] one man's wit, and all men's wisdom.”
— John Russell, 1st Earl Russell
Remark to James Mackintosh on October 6, 1830, reported in his posthumous memoir, Memoirs of the Life of the Right Honourable Sir James Mackintosh, Vol. 2 (1836), p. 472 http://books.google.com/books?id=wHM4AAAAYAAJ&q=%22one+man's+wit+and+all+men's+wisdom%22&pg=PA472#v=onepage
Variante: [A proverb is] the wisdom of many and the wit of one.