compelling vs incontestable

compelling

adj
  • Strongly or irresistibly evoking interest or attention. 

  • Forceful. 

noun
  • An act of compulsion; an obliging somebody to do something. 

incontestable

adj
  • Not contestable; indisputable; certain 

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