Definition of "irrationality" []

• The state or quality of being irrational. (noun)
• An irrational idea, expression, or act. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "It seems to work best for me, by the way, when I know why a certain irrationality is there, even if I never tell the reader."
• "While this kind of irrationality is certainly possible, there is no empirical evidence for it (and believe me, many of us have looked)."
• "It's rational to believe that irrationality is an ineliminable aspect of human mentality."