presupposition vs theorism

presupposition

noun
  • An assumption or belief implicit in an utterance or other use of language. 

  • An assumption made beforehand; a preliminary conjecture or speculation. 

  • The act of presupposing. 

theorism

noun
  • Synonym of theory 

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