debase vs purify

debase

verb
  • To lower in character, quality, or value; to degrade. 

  • To lower the value of (a currency) by reducing the amount of valuable metal in the coins. 

purify

verb
  • To cleanse, or rid of impurities. 

  • To become pure. 

  • To free from guilt or sin. 

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