Irrationally.

out of (all) reason: unreasonable; absurd, incredible; also as adverbial phrase.

In a manner not guided by or based upon reason, good sense, or sound judgement; unjustifiably; illogically.

Of a person or (occasionally) an animal: stupid, foolish; lacking intelligence or common sense.

In an irrational manner; in a way devoid of or contrary to reason; absurdly.

unreasonably.