“What has to do with your ability to fall asleep is not caffeine. It's having a clean conscience. I have a clean conscience so I can drink all the caffeine I want.”

Source: The Poisonwood Bible

Of her role in Planet of the Apes.
Interview on Cinema.com, 2001 http://www.cinema.com/articles/547/planet-of-the-apes-interview-with-helena-bonham-carter.phtml

The Time of the Hero (1963)

Source: Blood Noir

Source: Invasion of the Boy Snatchers

Interview with Matt Bai (2003)

Mr. Rochester to Jane (Ch. 14)
Jane Eyre (1847)

Letter to the Louis D. Oaks, Los Angeles Chief of Police (17 May 1923)
Context: I intend to do what little one man can do to awaken the public conscience, and in the meantime I am not frightened by your menaces. I am not a giant physically; I shrink from pain and filth and vermin and foul air, like any other man of refinement; also, I freely admit, when I see a line of a hundred policeman with drawn revolvers flung across a street to keep anyone from coming onto private property to hear my feeble voice, I am somewhat disturbed in my nerves. But I have a conscience and a religious faith, and I know that our liberties were not won without suffering, and may be lost again through our cowardice. I intend to do my duty to my country.

As quoted in "Holocaust heroine's survival tale" by Adam Easton in BBC News (3 March 2005)
Context: Let me stress most emphatically that we who were rescuing children are not some kind of heroes. Indeed, that term irritates me greatly. The opposite is true. I continue to have pangs of conscience that I did so little.