inconsistent vs unflappable

inconsistent

adj
  • Lacking internal consistency; self-contradicting; not compatible with itself. 

  • Not consistent or coherent in thought or behavior. 

  • Having the property that a contradiction can be derived. 

  • Not compatible (with another thing); incompatible, discrepant, at odds. 

unflappable

adj
  • Remaining composed and level-headed at all times; impossible to fluster; not becoming frustrated or irritated easily. 

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