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square of opposition

American  

noun

Logic.
  1. a diagrammatic representation of the opposition of categorical propositions.


square of opposition British  

noun

  1. See opposition

"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

Etymology

Origin of square of opposition

First recorded in 1860–65