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1. Irrational thought, expression, or behavior; irrationality.
2. Belief in feeling, instinct, or other nonrational forces rather than reason.


(ɪˈræʃ ə nlˌɪz əm)

1. irrationality in thought or action.
2. a theory that nonrational forces govern the universe.
ir•ra′tion•al•ist, adj., n.
ir•ra`tion•al•is′tic, adj.


1. a theory that nonrational forces govern the universe.
2. any attitude or set of beliefs having a nonrational basis, as nihilism. — irrationalist, n., adj.irrationalistic, adj.
See also: Philosophy
References in periodicals archive ?
Was it the result of his usual irrationalism, or of domestic politics?
The Freethinker attacked religion, irrationalism, and all kinds of censorship, and did so with wit and fervor.
SHE WRITES THAT OUR "TIME OF MORAL panic" is unprecedented, "driven by secularist rather than religious irrationalism.
I had no control over it and the pain was building but it was not physical pain, rather a sense of irrationalism with uncontrollable anxiety.
So the philosopher's explanation is really the old irrationalism of the gospel of John.
Having established Islamophobia as an undeniable fact, the Republican presidential candidate has now managed to expose the profound irrationalism of such tribalist hatreds.
If violence and irrationalism is a strength, I don't have it, I still regret killing that rat.
Would they have acknowledged that this is the kind of thing that can happen when anti-intellectual intellectuals steer a culture for decades into the dismal depths of irrationalism and emotionalism?
Facets of Russian Irrationalism Between Art and Life: Mystery Inside Enigma
The carnage at the BKU and earlier at the Army School in Peshawar is a reminder that irrationalism is seeping in and needs to be repulsed.
He argues that while the modern "rational domination of nature in science and technology" and the "violence of absolutist claims" may seem to "require above all a restraining of reason," the true necessity is a recovery of reason's scope: "It is not the grandeur of reason but its impoverishment that leads to oppressive rationalism and the arbitrary irrationalism inseparable from it.
Eco says irrationalism depends on the cult of action for action's sake.