hedonism vs self-gratification

hedonism

noun
  • A general devotion to the pursuit of pleasure. 

  • The belief that pleasure or happiness is the highest good in life. Some hedonists, such as the Epicureans, have insisted that pleasure of the entire mind, not just pleasure of the senses, is the highest good. 

self-gratification

noun
  • Self-satisfaction. 

  • Masturbation. 

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