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the principle that two expressions satisfy exactly the same predicates if and only if they both refer to the same subject
the weaker principle that if
whatever is true of
is true of
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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