big-headedness vs egoism

big-headedness

noun
  • The state or quality of being big-headed. 

egoism

noun
  • The tendency to think selfishly with exclusive self-interest in mind. 

  • Egotism (tendency to talk excessively about oneself). 

  • The belief that moral behavior should be directed toward one's self-interest only. 

How often have the words big-headedness and egoism occurred in a corpus of books? (source: Google Ngram Viewer )