assertion vs problem

assertion

noun
  • The act of asserting; positive declaration or averment. 

  • A statement in a program asserting a condition expected to be true at a particular point, used in debugging. 

  • A statement or declaration which lacks support or evidence. 

  • Maintenance; vindication 

  • Something which is asserted; a declaration; a statement asserted. 

problem

noun
  • Objection. 

  • A difficulty that has to be resolved or dealt with. 

  • A puzzling circumstance. 

  • A set of moves required to complete a climb. 

  • A question to be answered, schoolwork exercise. 

  • Difficulty in accepting or understanding or refusal to accept or understand. 

adj
  • Causing a problem; problematic; troublesome. 

  • Difficult to train or guide; unruly. 

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