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numerical identity

British  

noun

  1. logic the relation that holds between two relata when they are the selfsame entity, that is, when the terms designating them have the same reference Compare qualitative identity See also Leibnitz's law

"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