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principle of indifference

British  

noun

  1. the principle that, in the absence of any reason to expect one event rather than another, all the possible events should be assigned the same probability See mathematical probability

"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