While attending her mother's funeral, a woman meets a man she's never seen before. She quickly believes him to be her soulmate and falls head over heels. But she forgets to ask for his number, and when the wake is over, try as she might, she can't track him down. A few days later she murders her sister. Why? If the first answer that springs to your mind is some variation of jealousy and revenge -- she discovers her sister has been seeing the man behind her back -- then you are in the clear. But if your first response to this puzzle is "because she was hoping the man would turn up to her sister's funeral as well", then by some accounts you have the qualities that might qualify you to be a cold-blooded killer -- or a captain of industry, a nerveless surgeon, a recruit for the SAS -- or which may well make you a commission-rich salesman, a winning barrister, a charismatic clergyman or a red-top journalist. The little parable purports to reveal those qualities -- an absence of emotion in decision making, a cold focus on outcomes, an extremely ruthless and egocentric logic -- which tend to show up in disproportionate degrees in all those individuals. There is a problem though. When Kevin Dutton , the author of this compulsive quest into the psychopathic mind, tried the question on some real psychopaths, not one of them came up with the "second funeral" motive. As one commented: