assume vs disbelieve

assume

verb
  • To authenticate by means of belief; to surmise; to suppose to be true, especially without proof 

  • To receive, adopt (a person) 

  • To adopt a feigned quality or manner; to claim without right; to arrogate 

  • To take on a position, duty or form 

  • To adopt (an idea or cause) 

disbelieve

verb
  • To not believe; to exercise disbelief. 

  • To actively deny (a statement, opinion or perception). 

  • To cease to believe. 

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