What does the word conscience mean?

Usage examples for conscience

  1. Upon my conscience, I wonder the dogs did not hunt you. – The Adventures of Roderick Random by Tobias Smollett
  2. He has no conscience at all to think of a gal of nineteen! – Jack Tier or The Florida Reef by James Fenimore Cooper
  3. I thought I could not in conscience keep her in this place any longer. – The Autobiography of Madame Guyon by Jeanne Marie Bouvier de La Motte Guyon