For example, he gave people a test consisting of very easy math questions--but without giving them nearly enough time to finish. On average, people got four right out of 20. Then he had people take the test, score it themselves, shred the answer sheet and tell him how they did. Suddenly the average jumped to seven.
He repeated the experiment, paying people according to how many right answers they got. Same result. "Everybody cheated, but just a little." Even when there was no chance of getting caught--the evidence was shredded and participants paid themselves from a jar of money with over $100--nobody claimed 20 right answers. They just padded their results by a bit.
But then he tried another variation: Before doing the test, he asked one group of subjects to name 10 books they had read in high school. He asked another group to name as many of the Ten Commandments as they could remember. The group that listed the books followed the same pattern as the earlier test--they all cheated a little. But the group that named the commandments was different: Nobody cheated at all!
"Just the act of contemplating morality eliminated cheating," Ariely explains.
Which is what going to church or reading the bible regularly is really all about, right?