callous vs softhearted

callous

adj
  • Emotionally hardened; unfeeling and indifferent to the suffering/feelings of others. 

  • Having calluses, or relating to calluses. 

softhearted

adj
  • Easily moved to sorrow or pity. 

  • Willing to accept criticism. 

  • Gentle; kind; sympathetic. 

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