One other thing: when we decide to behave well and our first steps are successful, we often achieve a self-fulfilling momentum—Griffin called it “cruise control”—where we don’t have to try as hard to be good. Like getting through the first four days of a strict diet, if we can handle the initial stages of inhibiting our undesirable impulses, we’re less likely to backslide. We don’t want to waste the gains of our behavioral investment. Good behavior becomes the sunk cost we hate to sacrifice.
