callous vs solicitous

callous

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

  • Having calluses, or relating to calluses. 

solicitous

adj
  • In an anxious or distressed way. 

  • In an eager way. 

  • In a conscientious way, often with kindness. 

  • Disposed to solicit; eager to obtain something desirable, or to avoid anything evil. 

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