certainty vs concept

certainty

noun
  • The state of being certain. 

  • A fact or truth unquestionably established. 

  • An instance of being certain. 

concept

noun
  • An abstract and general idea; an abstraction. 

  • A description of supported operations on a type, including their syntax and semantics. 

  • Understanding retained in the mind, from experience, reasoning and imagination; a generalization (generic, basic form), or abstraction (mental impression), of a particular set of instances or occurrences (specific, though different, recorded manifestations of the concept). 

verb
  • to conceive; to dream up 

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