principled vs unscrupulous

principled

adj
  • Based on, having, or manifesting principles 

  • strongly adhering to, or heedful of, guiding beliefs or moral rules 

unscrupulous

adj
  • Without scruples; immoral. 

  • Contemptuous of what is right or honorable. 

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