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.

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.
See also:
  • a good example is the best sermon
  • teach a man to fish
  • it takes a village
  • village
  • a burnt child dreads the fire
  • burnt
  • bad workers always blame their tools
  • better bend than break
  • the best-laid plans
  • the best-laid plans go astray
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.
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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.
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PAUL SCHOLES has been one of the best players in the Premiership this season - but you cannot teach an old dog new tricks.
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"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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