optimism vs world-weariness

optimism

noun
  • the doctrine that this world is the best of all possible worlds 

  • a tendency to expect the best, or at least, a favourable outcome 

  • the belief that good will eventually triumph over evil 

world-weariness

noun
  • The state or characteristic of being world-weary. 

How often have the words optimism and world-weariness occurred in a corpus of books? (source: Google Ngram Viewer )