egotism vs self-interest

egotism

noun
  • Egoism (belief that behavior should be directed towards one's self-interest). 

  • A belief that one is superior to or more important than others. 

  • The result or product of being egoistic. 

  • A tendency to talk excessively about oneself. 

self-interest

noun
  • One's personal interest or advantage, especially when pursued without regard for others. 

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