cognizance vs thoughtlessness

cognizance

noun
  • An emblem, badge or device, used as a distinguishing mark by the body of retainers of a royal or noble house. 

  • Notice or awareness. 

  • Jurisdiction. 

thoughtlessness

noun
  • heedless disregard for the consequences of one's actions 

  • disregard for other's feelings 

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