introspection vs reverie

introspection

noun
  • A looking inward; specifically, the act or process of self-examination, or inspection of one's own thoughts and feelings; the cognition which the mind has of its own acts and states 

reverie

noun
  • A state of dreaming while awake; a loose or irregular train of thought; musing or meditation; daydream. 

  • An extravagant conceit of the imagination; a vision. 

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