The point is to keep him feeling that he has something, other than the Enemy and courage the Enemy supplies, to fall back on, so that what was intended to be a total commitment to duty becomes honeycombed all through with little unconscious reservations. By building up a series of imaginary expedients to prevent 'the worst coming to the worst' you may produce, at that level of his will which he is not aware of, a determination that the worst shall not come to the worst.
C S Lewis, The Screwtape Letters, p.163
