A prisoner was found guilty of murder and sentenced to be executed by beheading at dawn the following day. He bitterly contested this judgment with the words, “I performed that crime more than thirty years ago. Since then, my personality has changed; so has my entire body, and in fact there isn't a single molecule inside me now that is the same as when the victim was strangled. I'm a completely different individual from the fellow who performed the deed. If I am decapitated tomorrow morning, you will be guilty of taking the life of an innocent man. How will the executioner live with his conscience after such an injustice?”

“His conscience will bother him a lot, if what you say is true,” replied the judge, “and for many days and weeks he will feel acute anguish. But as more time passes, his personality will change and the molecules inside his body will be replaced one by one until he becomes a completely new individual, and that future individual can't possibly be held responsible for hacking off your head, so don't worry!”

¶ When smug people meet, the smuggest will prevail.