probity vs propriety

probity

noun
  • Integrity, especially of the quality of having strong moral principles; decency and honesty. 

propriety

noun
  • Correctness in behaviour and morals; good manners, seemliness. 

  • The fact of possessing something; ownership. 

  • Suitability, fitness; the quality of being appropriate. 

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