Source: Annie Hall: Screenplay
“Those who can -- do. Those who can't -- teach.”
“Those who know, do. Those that understand, teach.”
This and many similar quotes with the same general meaning are misattributed to Aristotle as a result of Twitter attribution decay. The original source of the quote remains anonymous. The oldest reference resides in the works of George Bernard Shaw, Man and Superman (1903): "Maxims for Revolutionists", where he claims that “He who can, does. He who cannot, teaches.”. However, the related quote, "Those who can, do. Those who understand, teach" likely originates from Lee Shulman in his explanation of Aristotlean views on professional mastery: Source: Shulman, L. S. (1986). Those who understand: Knowledge growth in teaching. Educational Researcher, 15(2), 4 - 14. Stable URL: http://www.jstor.org/stable/1175860
Misattributed
Variant: Those who can, do, those who cannot, teach.
“Those who can kill themselves do, and those who can’t, teach philosophy.”
Source: The Philosopher's Apprentice (2008), Chapter 13 (p. 295)
“The authority of those who teach is often an obstacle to those who want to learn.”
“It's those who lie outside ordinary experience who have the most to teach us.”
Malcolm Gladwell (2008). Outliers: The Story of Success. p. 198
“The best of those amongst you is the one who learns the Qur’an and then teaches it to others.”
Al-Amali of Shaykh at-Tusi, Volume 1, Page 5
Shi'ite Hadith
“Those you cannot teach to fly, teach to fall faster.”
“You can't teach an old dogma new tricks.”
Source: Attributed to Parker after her death, by Robert E. Drennan The Algonquin Wits (1968), p. 124. However the same quip appears anonymously fifteen years earlier, in the trade journal Sales Management (Chicago: Dartnell Corp., 1918-75), vol. 70 (Survey of Buying Power, 1953), p. 80: "Marxism never changes. You can’t teach an old dogma new tricks."
