lapalissade vs prosaism

lapalissade

noun
  • An obvious, self-evident truth, especially humorously so; a tautology or truism. 

prosaism

noun
  • A manner, quality, expression, style, phrase or word that is prosaic. 

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