Right now, as I write this, I am at peak integrity, but with every minute that passes, my moral fiber is weakening, like a cereal flake in milk. I don’t notice it, but if there are decisions or tasks requiring personal discipline, I should take care of them quickly—by this afternoon, I will be defenseless against my baser instincts.
So say Maryam Kouchaki and Isaac Smith, researchers into organizational behavior, in a new paper in the journal Psychological Science. The idea that people can be more or less moral at different times goes back to the earliest recorded stories people told about each other: Achilles is both merciless killer and tender friend, Dr. Jekyll is Mr. Hyde. What’s notable about the hypothesis Kouchaki and Smith set out to prove is that a person’s moral upstandingness erodes over the course of each day, broken down in a process as regular and as ineluctable as digestion.
The paper sets out to show the effects on moral decision-making of a phenomenon called “ego depletion,” an influential explanation of human behavior first advanced by the psychologist Roy Baumeister. The basic insight is that a person’s store of self-control is finite, and can be depleted. Like a muscle, our self-control weakens when we use it and is restored when we rest it. In one of his best-known studies, Baumeister had subjects sit in a room with a bunch of chocolate cookies. Some of them got to eat the cookies, others had to eat radishes. The subjects were later given a difficult math problem to solve, and the radish-eaters gave up sooner than the cookie-eaters. Concentration requires willpower, and they had already run down their willpower resisting the sweets.
It isn’t just in artificially torturous situations dreamt up by psychologists that we exhaust our willpower, though. It happens all the time in real life. Every decision, no matter how small, uses up some of it—what to wear to work, what to eat for breakfast, whether to tell a white lie about why you’re late for a meeting. A person can minimize those decisions in an attempt to husband one’s decision-making capacity—President Obama, citing the ego depletion literature, wears only gray or blue suits for this reason—but one can’t escape all of them. Moving through one’s day, there are inevitably a host of small decisions demanding to be made.
To the extent that acting ethically is a matter of mastering the temptation to do the wrong thing, Baumeister’s radish-eaters would also be more likely to cheat or lie than those who hadn’t already had to resist gustatory temptation. Or if they had less of a chance to replenish their reserves of self-control: Other research has shown that less sleep is correlated with less-ethical behavior in a workplace.
Kouchaki and Smith’s study set out to see whether that steady onslaught of small daily decisions means that people are inevitably more moral in the morning, when their self-regulatory resources haven’t yet been taxed, than they are in the afternoon. To a dramatic extent, the researchers found that they were. In one study, test subjects were randomly divided into a morning group and an afternoon group and given a chance to lie to earn more money. The participants in the afternoon group were 50 percent more likely to lie than those in the morning group. Given a math test on which they could easily cheat, subjects in a second study cheated on nearly twice as many questions if they took the test in the afternoon than if they took it in the morning.
Asked on the phone if he has changed anything in his own life because of his finding, Smith said he hasn’t. Still, he thinks there are ways to mitigate the effect. He points out that work by Baumeister and others has shown that, just as it does with real muscles, eating—like rest—helps replenish the strength of our decision muscle, so naps and snacks can help slow the transition to afternoon’s Mr. Hyde. Also in the paper, he and Kouchaki suggest that “morally relevant tasks should be deliberately ordered throughout the day. Perhaps organizations, for instance, need to be more vigilant about combating the unethical behavior of customers (or employees) in the afternoon than in the morning.”