affirmation vs negation

affirmation

noun
  • A form of self-forced meditation or repetition; autosuggestion. 

  • That which is affirmed; a declaration that something is true. 

  • The solemn declaration made by Quakers and others incapable of taking an oath. 

negation

noun
  • A proposition which is the contradictory of another proposition and which can be obtained from that other proposition by the appropriately placed addition/insertion of the word "not". (Or, in symbolic logic, by prepending that proposition with the symbol for the logical operator "not".) 

  • A denial or contradiction. 

  • The logical operation which obtains such (negated) propositions. 

  • The act of negating something. 

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