dispassionate vs monomaniacal

dispassionate

adj
  • not showing, and not affected by, emotion, bias, or prejudice 

monomaniacal

adj
  • Fanatical, or obsessed with one cause or idea to the exclusion of other concerns. 

  • Of or relating to a monomaniac. 

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