fallacious vs unsound

fallacious

adj
  • Deceptive or misleading. 

  • Characterized by fallacy; false or mistaken. 

unsound

adj
  • Not good, unreliable. 

  • Not whole, not solid, defective. 

  • Infirm, diseased. 

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