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Never give a sucker an even break

Don't hesitate to take advantage of a fool.

Note

This saying served as the title for one of the films of the comedian W. C. Fields.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Idioms and Phrases with never give a sucker an even break

never give a sucker an even break

Don't allow a person who's easily duped a fair chance, as in He's always trying to give out expired coupons for his store, firmly believing in never giving a sucker an even break. Probably a direct quotation, it has been attributed to showman P. T. Barnum (responsible for the oft-quoted “There's a sucker born every minute”); and comedian W. C. Fields (who popularized it in one of his films); and theater manager Edward Francis Albee, the most probable of the three. [Slang; early 1900s]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.