His problem, he realized finally, was that (all assertions of economists to the contrary) his preferences were not transitive. Because he was lazy, he preferred doing nothing to doing good. Because he was easily bored, he preferred doing evil to doing nothing. And because he had a guilty conscience, he preferred doing good to doing evil. Sometimes it took him months to go through the cycle. Sometimes it all happened in a single afternoon, as he started off helping his neighbor move, got tired and went home to watch the American Idol marathon, got bored and started vandalizing Wikipedia, and then felt guilty about it.