illogical vs imbecilic

illogical

adj
  • Contrary to logic; lacking sense or sound reasoning. 

imbecilic

adj
  • like or as an imbecile; so senseless as to be laughable; absurd, foolish, stupid, idiotic. 

How often have the words illogical and imbecilic occurred in a corpus of books? (source: Google Ngram Viewer )