Mar 13 JDN 2459652

One of the central insights of cognitive and behavioral economics is that understanding the limitations of our own rationality can help us devise mechanisms to overcome those limitations—that knowing we are not perfectly rational can make us more rational. The usual term for this is a somewhat vague one: behavioral economists generally call it simply sophistication.

For example, suppose that you are short-sighted and tend to underestimate the importance of the distant future. (This is true of most of us, to greater or lesser extent.)

It’s rational to consider the distant future less important than the present—things change in the meantime, and if we go far enough you may not even be around to see it. In fact, rationality alone doesn’t even say how much you should discount any given distance in the future. But most of us are inconsistent about our attitudes toward the future: We exhibit dynamic inconsistency.

For instance, suppose I ask you today whether you would like $100 today or $102 tomorrow. It is likely you’ll choose $100 today. But if I ask you whether you would like $100 365 days from now or $102 366 days from now, you’ll almost certainly choose the $102.

This means that if I asked you the second question first, then waited a year and asked you the first question, you’d change your mind—that’s inconsistent. Whichever choice is better shouldn’t systematically change over time. (It might happen to change, if your circumstances changed in some unexpected way. But on average it shouldn’t change.) Indeed, waiting a day for an extra $2 is typically going to be worth it; 2% daily interest is pretty hard to beat.

Now, suppose you have some option to make a commitment, something that will bind you to your earlier decision. It could be some sort of punishment for deviating from your earlier choice, some sort of reward for keeping to the path, or, in the most extreme example, a mechanism that simply won’t let you change your mind. (The literally classic example of this is Odysseus having his crew tie him to the mast so he can listen to the Sirens.)

If you didn’t know that your behavior was inconsistent, you’d never want to make such a commitment. You don’t expect to change your mind, and if you do change your mind, it would be because your circumstances changed in some unexpected way—in which case changing your mind would be the right thing to do. And if your behavior wasn’t inconsistent, this reasoning would be quite correct: No point in committing when you have less information.

But if you know that your behavior is inconsistent, you can sometimes improve the outcome for yourself by making a commitment. You can force your own behavior into consistency, even though you will later be tempted to deviate from your plan.

Yet there is a piece missing from this account, often not clearly enough stated: Why should we trust the version of you that has a year to plan over the version of you that is making the decision today? What’s the difference between those two versions of you that makes them inconsistent, and why is one more trustworthy than the other?

The biggest difference is emotional. You don’t really feel $100 a year from now, so you can do the math and see that 2% daily interest is pretty darn good. But $100 today makes you feel something—excitement over what you might buy, or relief over a bill you can now pay. (Actually that’s one of the few times when it would be rational to take $100 today: If otherwise you’re going to miss a deadline and pay a late fee.) And that feeling about $102 tomorrow just isn’t as strong.

We tend to think that our emotional selves and our rational selves are in conflict, and so we expect to be more rational when we are less emotional. There is some truth to this—strong emotions can cloud our judgments and make us behave rashly.

Yet this is only one side of the story. We also need emotions to be rational. There is a condition known as flat affect, often a symptom of various neurological disorders, in which emotional reactions are greatly blunted or even non-existent. People with flat affect aren’t more rational—they just do less. In the worst cases, they completely lose their ability to be motivated to do things and become outright inert, known as abulia.

Emotional judgments are often less accurate than thoughtfully reasoned arguments, but they are also much faster—and that’s why we have them. In many contexts, particularly when survival is at stake, doing something pretty well right away is often far better than waiting long enough to be sure you’ll get the right answer. Running away from a loud sound that turns out to be nothing is a lot better than waiting to carefully determine whether that sound was really a tiger—and finding that it was.

With this in mind, the cases where we should expected commitment to be effective are those that are unfamiliar, not only on an individual level, but in an evolutionary sense. I have no doubt that experienced stock traders can develop certain intuitions that make them better at understanding financial markets than randomly chosen people—but they still systematically underperform simple mathematical models, likely because finance is just so weird from an evolutionary perspective. So when deciding whether to accept some amount of money m1 at time t1 and some other amount of money m2 at time t2, your best bet is really to just do the math.

But this may not be the case for many other types of decisions. Sometimes how you feel in the moment really is the right signal to follow. Committing to work at your job every day may seem responsible, ethical, rational—but if you hate your job when you’re actually doing it, maybe it really isn’t how you should be spending your life. Buying a long-term gym membership to pressure yourself to exercise may seem like a good idea, but if you’re miserable every time you actually go to the gym, maybe you really need to be finding a better way to integrate exercise into your lifestyle.

There are no easy answers here. We can think of ourselves as really being made of two (if not more) individuals: A cold, calculating planner who looks far into the future, and a heated, emotional experiencer who lives in the moment. There’s a tendency to assume that the planner is our “true self”, the one we should always listen to, but this is wrong; we are both of those people, and a life well-lived requires finding the right balance between their conflicting desires.