"Bargaining Chip": Antedating & Mystery

[Fred Shapiro]

The earliest citation in OED for "bargaining chip," contributed by me, is
dated 1965.  Here is an antedating I have found:

1960 E. B. Potter _Sea Power: A Naval History_ 548  In the event of a
British defeat, his [Churchill's] government might be turned out of office
and another group might use the fleet as bargaining chips at the surrender
table.

For years I have been posing a question about "bargaining chip" that no
one has yet answered.  This is widely assumed to be a poker metaphor, but
I do not know of chips being used for bargaining in poker or any other
game.  What exactly is the metaphor?

Fred Shapiro


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Fred R. Shapiro                             Editor
Associate Librarian for Public Services     YALE DICTIONARY OF QUOTATIONS
  and Lecturer in Legal Research            Yale University Press,
Yale Law School                             forthcoming
e-mail: fred.shapiro at yale.edu               http://quotationdictionary.com
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