 To embark on the enterprise of subjecting human conduct to rules involves … a commitment to the view that man is … a responsible agent, capable of understanding and following rules…. Every departure from the principles of law’s inner morality is an affront to man’s dignity as a responsible agent. To judge his actions by unpublished or retrospective laws, or to order him to do an act that is impossible, is to convey … your indifference to his powers of self-determination. (Fuller 1964: 162)