certainty vs skepticism

certainty

noun
  • The state of being certain. 

  • A fact or truth unquestionably established. 

  • An instance of being certain. 

skepticism

noun
  • Doubt or disbelief of religious doctrines 

  • The practice or philosophy of being a skeptic. 

  • The doctrine that absolute knowledge is not possible 

  • A studied attitude of questioning and doubt 

  • A methodology that starts from a neutral standpoint and aims to acquire certainty though scientific or logical observation. 

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