“A self-taught man usually has a poor teacher and a worse student” is an old line of unknown authorship. “He (Charles Haddon Spurgeon—ed.) is a self-taught man, and contrary to what was said of another distinguished self-taught man, that he had a very poor teacher, Mr. Spurgeon had a very good and wise teacher” was cited in 1883. The other distinguished self-taught man was probably Scottish geologist and writer Hugh Miller (1802-1854). “For many a man who teaches himself, has a poor teacher, and a stupid and refractory pupil” was cited in 1910.
 
“A self-made man who had a poor teacher and a worse student” was said in 1945 of Benito Mussolini (1883-1945). “A self-taught man usually has a poor teacher and a worse student” was cited without attribution in 1968. “A self-taught person usually has a poor teacher and a worse student” was credited in 1975 to Canadian-American bandleader Guy Lombardo (1902-1977). New York-based comedian Henny Youngman (1906-1998) is often credited with the line, but he didn’t coin it and possibly never said it.
 
   
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July 1883, The Chautauquan, “Rev. Charles Haddon Spurgeon” by A. A. Livermore, pg. 565, col. 2:
He is a self-taught man, and contrary to what was said of another distinguished self-taught man, that he had a very poor teacher, Mr. Spurgeon had a very good and wise teacher.
 
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Autobiography and Personal Tributes
By William Phillips Tilden
Boston, MA: Press of Geo. H. Ellis
1891
Pg. 286 (Appendix):
It was said of one who was self-taught that he had a very poor teacher, but Mr. Tilden was favored in this respect.
 
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February 1910, Every Where (Brooklyn, NY), “The Two February Americans,” pg. 329:
Lincoln, on the contrary, was a natural scholar — self taught, but judiciously so, which is well worth noting: for many a man who teaches himself, has a poor teacher, and a stupid and refractory pupil.
   
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Canadian Landscape Painters
By Albert Henry Robson
Toronto, ON: Ryerson Press
1932  
Pg. 47:
Always described as self taught, his work refutes that classic witticism, “the self taught artist had a very poor teacher,” for O’Brien’s work is conspicuous for its accomplished technique and able draughtsmanship.
 
19 July 1945, Tucson (AZ) Daily Citizen, “Ciano,” pg. 4, col. 4:
“He (Bottai, a minister of national education—ed.) calls him (Mussolini—ed.) ‘a self-made man who had a poor teacher and a worse student.’”
 
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20,000 Quips & Quotes
By Evan Esar
New York, NY: Barnes & Noble Books
1995, ©1968
Pg. 797:
A self-taught man usually has a poor teacher and a worse student.
 
27 August 1975, The Daily Times-News (Burlington, NC), “Readin’, Writin’ And All That” by Paul Steiner (Women’s News Service), pg. 1C, col. 2:
“A self-taught person usually has a poor teacher and a worse student.”—Guy Lombardo.
 
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Phillips’ Book of Great Thoughts, Funny Sayings:
A Stupendous Collection of Quotes, Quips, Epigrams, Witticisms, and Humorous Comments:
For Personal Enjoyment and Ready Reference
By Bob Phillips
Wheaton, IL: Tyndale House
1993
Pg. 106:
EDUCATION.
A self-taught man usually has a poor teacher and a worse student
 
Google Books
Teachers:
Jokes, Quotes, and Anecdotes
Edited by Patrick Regan
Kansas City, MO: Andrews McMeel Publishing
2001
Pg. 138:
A self-taught man usually has a poor teacher and a worse student. — Henny Youngman
 
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Henny Youngman: A self-taught man usually has a poor teacher and a worse student. | #Quotes
1:23 AM - 20 Oct 2015