obduracy vs pusillanimity

obduracy

noun
  • The state of being obdurate, intractable, or stubbornly inflexible. 

pusillanimity

noun
  • The quality or state of being pusillanimous; the vice of being timid and cowardly, and thus not living up to one's full potential; pusillanimousness. 

How often have the words obduracy and pusillanimity occurred in a corpus of books? (source: Google Ngram Viewer )