daydream vs pessimism

daydream

noun
  • A spontaneous series of thoughts while awake not connected to immediate reality. 

verb
  • To have such a series of thoughts; to woolgather. 

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 daydream and pessimism occurred in a corpus of books? (source: Google Ngram Viewer )