“You’re never too old to learn something stupid”

“You’re never too old to learn something stupid” is a jocular one-line saying that has been printed on many images. Brooklyn humorist Sam Levenson (1911-1980) used the line since at least 1976 and printed it in his book, You Don’t Have to Be in Who’s Who to Know What’s What (1979).
   
 
Wikipedia: Sam Levenson
Samuel Levenson (December 28, 1911 – August 27, 1980) was an American humorist, writer, teacher, television host, and journalist.
         
7 July 1976, St. Louis (MO) Jewish Light, “Folk Humorist Sam Levenson: His Favorite Jokes Are His Own” by Jakki Savan, pg. 7, cols. 2-3:
In St. Louis, he spoke before a full house at Brith Sholom Kneseth Israel, entertaining his gathering with delightful observations on life and such words of wisdom as, “You’re never too old to learn something stupid.”
 
Old Fulton NY Post Cards
24 July 1976, Olean (NY) Times Herald, “American Comedy Way Automated” by Frank Stilley, pg. 16A, col. 5:
“Man is never too old to learn something stupid.”
(Spoken by Sam Levenson.—ed.)
     
27 April 1979, Minneapolis (MN) Tribune, “Humor and what it means to society: The joke’s on us” by Jeff Strickler, pg. 2C, col. 3:
“From generation to generation, certain truths have been handed down like ‘You’re never too old to learn something stupid.’ No, that’s a real, proven truth.’”
(Spoken by Sam Levenson.—ed.)
 
24 June 1979, Morning Advocate, (Baton Rouge, LA), “Sam Levenson Record Life’s Humor on Cards” by Phil Thomas (AP Book Editor), pg. 8-C, col. 1:
Then he dashes off with great glee a few zingers:
   
“To praise wisdom is great, but you’re never too old to learn something stupid.”
 
26 September 1998, The Gazette (Montreal, Quebec), “Quote,” pg. A1:
You’re never too old to learn something stupid.
Anonymous
 
Twitter
T E N‏
@TeNsHoTs956
You’re never too old to learn something stupid. But, your never too young to be stupid. Damn people amuse me…Damn I just sneezed.
5:44 PM - 17 Dec 2007
       
Google Books
5,000 Great One Liners
Edited by Grant Tucker
London, UK: Biteback Publishing
2012
Pg. ?:
You’re never too old to learn something stupid.
 
Twitter

9GAG‏
@9GAG
You’re never too old to learn something stupid.
9:00 AM - 13 Mar 2013
 
Twitter
8joke‏
@8joke
You’re never too old to learn something stupid.
5:01 PM - 2 May 2013
   
Google Books
You Don’t Have to Be in Who’s Who to Know What’s What:
The Wit and Wisdom of Sam Levenson
By Sam Levenson
New York, NY: Open Road Distribution
2016 (Originally published in 1979)
Pg. ?:
There is what is known as Wisdom Literature of the most serious nature in every culture. There is also a Wisdom Literature that treats wisdom with wit:
 
“Who is wise?” asks the wise man, and being wise he answers it himself. “He is wise, indeed, who knows that you’re never too old to learn something stupid.”
 
Twitter
JokeBot 6000‏
@JokeBot6000
You’re never too old to learn something stupid.  #joke #oneliner
1:22 AM - 24 Jan 2018