\Ra`tion*al"i*ty\, n.; pl. {-ties}. [F.
rationalit['e], or L. rationalitas.]
The quality or state of being rational; agreement with
reason; possession of reason; due exercise of reason;
reasonableness.

      When God has made rationality the common portion of
      mankind, how came it to be thy inclosure? --Gov. of
                                               Tongue.

      Well-directed intentions, whose rationalities will
      never bear a rigid examination.          --Sir T.
                                               Browne.