You cannot teach an old dog new tricks

you can't teach an old dog new tricks

proverb You cannot teach some new skill or behavior to someone who is set in their ways. Good luck getting Grandpa to start going to yoga with you. You can't teach an old dog new tricks.
See also: dog, new, old, teach, trick
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

You cannot teach an old dog new tricks.

Prov. Someone who is used to doing things a certain way cannot change. (Usually not polite to say about the person you are talking to; you can say it about yourself or about a third person.) I've been away from school for fifteen years; I can't go back to college now. You can't teach an old dog new tricks. Kevin's doctor told him not to eat starchy food anymore, but Kevin still has potatoes with every meal. I guess you can't teach an old dog new tricks.
See also: cannot, dog, new, old, teach, trick
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
But the saying you cannot teach an old dog new tricks has never rung truer than with some customers in this restaurant.
WHOEVER said you cannot teach an old dog new tricks had not reckoned on Steve Simonsen.
They say that a steak cannot be fully appreciated if it is well done, but you cannot teach an old dog new tricks; and it is just as well, for I would have missed out on a delicious dish.
"You cannot teach an old dog new tricks. Terry Griffiths once said that Stephen Hendry steam-rollers players while I try to anaesthetise them."
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