Never underestimate the power of the human imagination. It fuels the vision of leaders who enrich their tribe. It powers fear, forcing individuals to sidestep danger.

Movie directors understand its potency. The film 'Jaws' achieved success by building up fear of a shark long before it appeared on stage. 'Alien' triggered fear early on by providing glimpses of the creature on board a space ship. The Blair Witch Project went one better by letting you sense, but never see, the evil force which was the subject of its mock documentary.