unreasoning

un- +‎ reasoning

unreasoning (comparative more unreasoning, superlative most unreasoning)

1. Lacking or without reason.
   • 1920, Edward Carpenter, Pagan and Christian Creeds, New York: Harcourt, Brace and Co., published 1921, page 196:

     When we consider the enormous amount of suffering and disease, both of mind and body, arising from the sex-suppression of which I have just spoken, especially among women, we see that mere unreasoning taboos - which possibly had their place and use in the past - can be tolerated no longer.