ardency vs pessimism

ardency

noun
  • Intensity of devotion. 

  • Intensity of light. 

  • Intensity of heat or burning. 

  • Intensity of feelings. 

pessimism

noun
  • A general belief that bad things will happen. 

  • The condition of being pessimal. 

  • The doctrine that this world is the worst of all possible worlds. 

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