ipse dixit vs ruling

ipse dixit

noun
  • An authority who makes such an assertion. 

  • A dogmatic and unproved proposition or dictum that is accepted solely on the authority of someone who is known to have asserted it. 

ruling

noun
  • An order or a decision on a point of law from someone in authority. 

adj
  • That rules; predominant; chief; reigning; controlling. 

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