free will vs opportunity

free will

noun
  • A person's natural inclination; unforced choice 

  • The ability to choose one's actions, or determine what reasons are acceptable motivation for actions, without predestination, fate etc. 

opportunity

noun
  • opportuneness 

  • A favorable circumstance or occasion. 

  • A chance for advancement, progress or profit. 

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