extortion vs self-control

extortion

noun

  • The practice of extorting money or other property by the use of force or threats. 

self-control

noun

  • The ability to control one's desires and impulses; willpower. 

verb

  • To control oneself or itself. 

How often have the words extortion and self-control occurred in a corpus of books? (source: Google Ngram Viewer )