" Atheist: 'I hear the voice of conscience, but I deny the reality of God.' St. Thomas: 'That is like listening to someone speak, but denying that anyone is there.' Atheist: 'That's right; nobody is.' St. Thomas: 'Then you deny not only God but conscience, because you consider it a hallucination.' Atheist: 'I misspoke. What I meant to say is that when I am listening to conscience, I am really listening to myself.' St. Thomas: 'Then you still deny conscience, because you deny its authority to judge you. Instead you claim to judge yourself, but no one can be judge in his own case. "

― J. Budziszewski , Commentary on Thomas Aquinas's Treatise on Law