impotence vs strength

impotence

noun
  • Inability to copulate or beget children; sterility, erectile dysfunction, etc. 

  • Powerlessness; incapacity. 

strength

noun
  • The intensity of a force or power; potency. 

  • The quality or degree of being strong. 

  • The strongest part of something; that on which confidence or reliance is based. 

  • A positive attribute. 

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