You may know the old parable of the Mexican fisherman. A banker meets a fisherman who works just a few hours a day and spends the rest of his time with family and friends. The banker can't help himself: Why not catch more fish? Buy more boats? Build a fleet? Do it for 20 years, sell the business and cash out — and then he could finally retire to a little fishing village to relax with the people he loves. Which, ironically, is exactly the life the fisherman already had. The usual lesson is...