The old theological deadlock between predestination and free-will serves admirably as an example of the sort of deadlock I mean. Take life at the level of common sensation and common experience and there is no more indisputable fact than man's freedom of will, unless it is his complete moral responsibility. But make only the least penetrating of analyses and you perceive a world of inevitable consequences, a rigid succession of cause and effect. Insist upon a flat agreement between the two, and there you are! The Instrument fails.