Walter Mitty vs wishful thinker

Walter Mitty

noun
  • A sad or pathetic person given to flights of fancy; a daydreamer. 

  • An imposter, especially one falsely claiming to have done military service. 

wishful thinker

noun
  • One who engages in wishful thinking. 

How often have the words Walter Mitty and wishful thinker occurred in a corpus of books? (source: Google Ngram Viewer )