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Buridan's ass

British  
/ ˈbjʊərɪdənz /

noun

  1. philosophy an example intended to show the deficiency of reason. An ass standing equidistant from two identical heaps of oats starves to death because reason provides no grounds for choosing to eat one rather than the other

"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 Buridan's ass

named after Jean Buridan , 14th-century French philosopher, to whom it was incorrectly attributed