unreason

from WordNet (r) 3.0 (2006)

unreason
    n 1: the state of being irrational; lacking powers of
         understanding [syn: {irrationality}, {unreason}]

from The Collaborative International Dictionary of English v.0.48

Unreason \Un*rea"son\, n. [Pref. un- not + reason.]
   Want of reason; unreasonableness; absurdity.
   [1913 Webster]

   {Abbot of Unreason}. See {Abbot of Misrule}, under {Abbot}.
      [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Unreason \Un*rea"son\, v. t. [1st pref. un- + reason.]
   To undo, disprove, or refute by reasoning. [Obs.]
   [1913 Webster]

         To unreason the equity of God's proceedings. --South.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

27 Moby Thesaurus words for "unreason":
      callowness, childishness, immaturity, imprudence, inadvisability,
      inattention, inconsideration, indiscreetness, indiscretion,
      inexpedience, injudiciousness, irrationality, pompousness,
      puerility, reasonlessness, recklessness, senselessness, stuffiness,
      thoughtlessness, unintelligence, unreasonableness, unsensibleness,
      unsoundness, unthoughtfulness, unwisdom, unwiseness, witlessness

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