rigor vs self-abnegation

rigor

noun
  • A feeling of cold with shivering accompanied by a rise in body temperature. 

self-abnegation

noun
  • The denial or invalidation of one's own needs, interests, etc. for the sake of another's; the setting aside of self-interest. 

  • An act of self-denial. 

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