incredulity vs surprise

incredulity

noun
  • Unwillingness or inability to believe; doubt about the truth or verisimilitude of something; disbelief. 

  • Religious disbelief, lack of faith. 

surprise

noun
  • The feeling that something unexpected has happened. 

  • Something unexpected. 

verb
  • To attack unexpectedly. 

  • To take unawares. 

  • To do something to (a person) that they are not expecting, as a surprise. 

  • To cause (someone) to feel unusually alarmed or delighted by something unexpected. 

  • To undergo or witness something unexpected. 

  • To cause surprise. 

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