David Solomon's career as an advice-giver began in the 5th grade when he advised a classmate, who complained of not getting enough allowance, to leave a ransom note on the front door, demanding what he wants, then hide in the woods until dark. "Leave a bag of money here tonight," the note said, "and your son will be returned to you safely." The boy's parents recognized their son's poorly disguised handwriting, of course, and were waiting for the...