For the past several centuries, most Westerners would have identified themselves fundamentally as Depraved Sinners. In this construct, sin is something you fight like a recurring cancer — part of a daily battle against evil.

But these days, people are more likely to believe in their essential goodness. People who live by the Good Person Construct try to balance their virtuous self-image with their selfish desires. They try to manage the moral plusses and minuses and keep their overall record in positive territory. In this construct, moral life is more like dieting: I give myself permission to have a few cookies because I had salads for lunch and dinner. I give myself permission to cheat a little because, when I look at my overall life, I see that I’m still a good person.

The Good Person isn’t shooting for perfection any more than most dieters are following their diet 100 percent. It’s enough to be workably suboptimal, a tolerant, harmless sinner and a generally good guy…

The key job in the Good Person Construct is to manage your rationalizations and self-deceptions to keep them from getting egregious. Ariely suggests you reset your moral gauge from time to time. Your moral standards will gradually slip as you become more and more comfortable with your own rationalizations. So step back. Break your patterns and begin anew. This is what Yom Kippur and confessionals are for.