conscience

Etymology

From Middle English conscience, from Old French conscience, from Latin conscientia (“knowledge within oneself”), from consciens, present participle of conscire (“to know, to be conscious (of wrong)”), from com- (“together”) + scire (“to know”).

noun

1. The ethical or moral sense of right and wrong, chiefly as it affects a person’s own behaviour and forms their attitude to their past actions.
   Your conscience is your highest authority.
   1949, Albert Einstein, as quoted by Virgil Henshaw in Albert Einstein: Philosopher Scientist, Never do anything against conscience, even if the state demands it.
   [“]Twer is not a friend of mine testifying against me reluctantly and for conscience’ sake, as the prosecution would have you believe. He is a spy, performing his paid job.[”] 1951, Isaac Asimov, Foundation, Panther Books Ltd, published 1974, part V: The Merchant Princes, chapter 14, page 175
   ‘Then the father has a great fight with his terrible conscience,’ said Munday with granite seriousness. ‘Should he make a row with the police […]? Or should he say nothing about it and condone brutality for fear of appearing in the newspapers? 1963, Margery Allingham, chapter 18, in The China Governess
2. (chiefly fiction, narratology) A personification of the moral sense of right and wrong, usually in the form of a person, a being or merely a voice that gives moral lessons and advices.
3. (obsolete) Consciousness; thinking; awareness, especially self-awareness.