ardor vs reluctance

ardor

noun
  • Intense heat. 

  • Great warmth of feeling; fervor; passion. 

  • Spirit; enthusiasm; passion. 

reluctance

noun
  • Hesitancy in taking some action. 

  • That property of a magnetic circuit analogous to resistance in an electric circuit. 

  • Unwillingness to do something. 

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