foolish

Adjective

foolish (comparative more foolish, superlative most foolish)

1. Lacking good sense or judgement as a general trait; unwise; stupid.
   • His wife and the neighbours lamented over his strange conduct, his dullness and melancholy, and began to think that he was grown foolish.1828, Thomas Keightley, The Fairy Mythology, volume I, London: William Harrison Ainsworth, page 318
   • Next season will, as ever, be a different matter, another problem for Conte to solve as he looks to extend his personal record of four straight league titles in club football across England and Italy. Given his hunger for more – more time, more detail, more work – only the brave or the foolish...2017 May 13, Barney Ronay, “Antonio Conte’s brilliance has turned Chelsea’s pop-up team into champions”, in the Guardian
2. (usually, decision, system) Not based on good sense or judgement; as a fool would do or conclude.
   • As a political system democracy seems to me extraordinarily foolish, but I would not go out of my way to protest against it. My servant is, so far as I am concerned, welcome to as many votes as he can get. I would very gladly make mine over to him if I could.1915, G[eorge] A. Birmingham [pseudonym; James Owen Hannay], chapter I, in Gossamer, New York, N.Y.: George H. Doran Company, →OCLC
3. Resembling or characteristic of a fool.