illogical vs insane

illogical

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

insane

adj
  • Exhibiting unsoundness or disorder of mind; not sane; utterly mad. 

  • Used by or relating to insane people. 

  • Causing insanity or madness. 

  • Extremely good; incredibly amazing. 

  • Characterized by insanity or the utmost folly; ridiculous; impractical. 

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