“A thief believes everybody steals” is a saying that has been printed on many images. Rather than find personal fault, the thief believes—or wants to believe—that everyone else is also a criminal.
 
“The common theif (sic) usualy (sic) believes everybody will steal” was printed in The Allen County Democrat (Lima, OH) on November 1, 1889.
 
“Every thief believes everybody steals” was printed in The Atchison Weekly Globe (Atchison, KS) on November 4, 1909. “A thief believes everybody steals” was printed in the book Country Town Sayings: A collection of paragraphs from the Atchison Globe (1911) by Edgar Watson Howe. The saying is usually credited to E. W. Howe (1853-1937).
 
   
Wikipedia: E. W. Howe
Edgar Watson Howe (May 3, 1853 – October 3, 1937), was an American novelist and newspaper and magazine editor in the late 19th and early 20th centuries. He was perhaps best known for his magazine, E.W. Howe’s Monthly. Howe was well traveled and known for his sharp wit in his editorials.
 
Newspapers.com
1 November 1889, The Allen County Democrat (Lima, OH), “Bully Brigham,” pg. 9, cols. 5-6:
In this connection let me say that it is an admitted truth that he who would himself betray his official trust for gain, really believes others equally depraved in morals. The common theif (sic) usualy (sic) believes everybody will steal.
(...)
R. MEHAFFEY.
 
Newspapers.com
3 November 1909, Cincinnati (OH) Enquirer, pg. 4, col. 2:
SUNFLOWER PHILOSOPHY.
[Atchison (Kan.) Globe.]
Every thief believes everybody steals.
 
Newspapers.com
4 November 1909, The Atchison Weekly Globe (Atchison, KS), pg. 4, col. 7:
GLOBE SIGHTS.
Every thief believes everybody steals.
 
Newspapers.com
11 November 1909, Great Falls (MT) Daily Tribune, pg. 8, col. 7:
Every thief believes everybody steals.
 
Newspapers.com
8 December 1909, The Topeka Daily State Journal (Topeka, KS), pg. 14, col. 3:
GLOBE SIGHTS.
[From the Atchison Globe.]
Every thief believes everybody steals.
 
Google Books
Country Town Sayings:
A collection of paragraphs from the Atchison Globe
By Edgar Watson Howe
Topkea, KS: Crane & Company
1911
Pg. 48:
A thief believes everybody steals.
     
Google Books
The Concise Columbia Dictionary of Quotations
By Robert Andrews
New York, NY: Columbia University Press
1992
Pg. 65:
A thief believes everybody steals.
Ed (E. W.) Howe (1853–1937)
American journalist, novelist
 
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$tuart K. Hayashi🌎💱
@legendre007
Edgar Watson Howe said that an old community saying was “A thief believes everybody steals.” I think a likewise truism is that the cribber believes no one shows any originality.
12:19 PM · Jan 6, 2020·Twitter Web App