I’ve just finished reading Walter Mischel’s book, The Marshmallow Test: Why Self-Control Is the Engine of Success. In the 1960s Mischel ran a series of experiments in which small children at Stanford’s Bing preschool were given a choice: there was a single marshmallow on a plate, and the researcher told each child that she had to leave the room for a little while; if the child wanted, they could eat the marshmallow at any time, but if they waited until the researcher returned, they could have two. The main purpose of the experiment was to measure differences in self-control, and to study what the successful kids did to keep themselves from gobbling the marshmallow immediately.
The experiment might never have become known outside the specialized world of psychology, except for one thing. The kids tested were classmates of Mischel’s daughters, and several years later he decided to see whether there was a correlation between self-control exhibited on the test and life results. He found a clear and strong correlation that was beyond what he expected; for example, those in the top third of self-control averaged 210 SAT points higher than those in the bottom third. These differences, and others, such as obesity rates and income, persisted over time as he continued to monitor results through the years.
By themselves, these results can be very disturbing. Does this mean that our success in life is so dependent on a single trait—self-control—that you’re born with and is easily measurable by the time you’re four years old? If you fail the marshmallow test at age four, are you doomed to a life of failure? Or is there something you can do about it?
Actually, there is a lot you can do about it, and low self-control does not have to be destiny.
Mischel’s key point is that self-control is not a fixed, unitary trait. It’s not fixed in the sense of being totally determined by our genes; it’s a product of our genes, our environment, and our learning. Most importantly, it’s a skill that can be learned, practiced, and strengthened. It’s also not unitary, which means that we don’t apply the same amount of self-control in every situation. We all have our own unique combination of hot and cool buttons. Bill Clinton is the poster child example for this. He obviously had enormous self-control that got him from a small town in Arkansas to the presidency, but not enough to prevent a sexual scandal once he got there.
The most surprising and potentially useful finding to me was about the relation between mindset and self-control. Researchers such as Roy Baumeister have told us that willpower and self-control are a finite resource, which means that exercising self-control in one task depletes your ability to exercise it as strongly in a subsequent task. This “strength model of self-control” has become an enormously influential and insidious idea. It’s insidious because it tells you that you can only do so much, and even that it’s OK to limit your aspirations for self-improvement. It tells you that it’s not your fault when you fail—it’s biology.
I’ve had my doubts about the strength theory for two reasons. Looking at the big picture, history contains so many examples of people who have accomplished great things without seeming to be affected by willpower limits, who have persevered in many situations despite hunger, fatigue and deep discouragement. Closer to home, I have been working for the past month on a deep work project, which has made me spend much longer blocks of time and attention working on tasks that require a lot of self-control. So far I’ve found that I can work much longer and get much more done than I previously thought possible, and the best part is that I now finish the day with more energy than before.
Yet despite those doubts about the theory, the idea that self-control is finite has lingered in the back of my mind and imposed limits on my work habits. For example, writing can take a lot of willpower, so after about a half hour of writing I start telling myself that it’s time to take a break; sometimes I give in and sometimes I make a conscious effort to try to power through my “limits”.
But Mischel tells us that those limits may be self-imposed. If we think our willpower is limited, we’ll be right. Fortunately, if we think it’s not limited, we’ll also be right. According to Mischel, our mindset about self-control also influences whether we suffer depletion. If we believe in the strength model, we do get depleted from difficult tasks; if we don’t believe in it, we can escape the effects and even gain more stamina and strength from tasks that require self-control. Even more promising, we can learn the new mindset and gain the same benefits.
Carol Dweck and fellow researchers ran studies that found that the amount of willpower fatigue that participants exhibited was affected by their prior beliefs about whether willpower was a limited resource. They also found that just teaching college students the new mindset carried over beyond the lab and led to less procrastination and reducing excess spending.
I learned first-hand about the power of mindset many years ago. When I was still in my 20s, I began having a lot of stomach issues, and went to several doctors to try to discover the cause. I remember one final test, after which the doctor told me they could find nothing physically wrong, so they assumed it was stress related. Literally from that moment on, my symptoms disappeared and have never returned. I figured since it was only in my mind, that I could change my mind.
I guess it shouldn’t be that surprising that our self-control can be affected by our mindset. Dweck has already shown us that our beliefs about whether intelligence is fixed or malleable can have a significant impact on what we attempt and achieve, and in effect can become self-fulfilling prophecies. I learned that even our mindset about stress can affect whether it helps or harms us.
Now it’s gratifying and enormously empowering to find that the same idea applies to self-control. If you know you can self-control your self-control, the sky is the limit!