affirmation vs auto-suggestion

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. 

auto-suggestion

noun
  • The practice of suggesting thoughts to oneself. 

  • An instance of suggesting a thought to oneself. 

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