The Power of Self Control 

The famous marshmallow experiment found a link between self-control at a young age and success in adulthood. Does this mean our fate is determined at birth? 

The Marshmallow Test

In the 1960s, Professor Walter Mischel, who taught at Stanford University and was the father of three young girls, ages 2 to 5, made an interesting observation. One day, after his daughter had turned four, he noticed something had changed. Up until then, she had wanted everything “right here, right now,” but from the age of four onwards, he could explain to her that if she waited patiently, she would get what she wanted—and it worked.

This realization led him to conduct an experiment on young children to test their self-control. He went to a local preschool and chose a room with no toys, pictures, or anything else that could distract the kids. In the room, there was only a chair and a small desk. On the desk, he placed two marshmallows. He invited a child into the room and explained that they could have one marshmallow right away, or if they waited for 20 minutes, they would get two marshmallows.

He left the room and recorded each child’s behavior with a hidden camera, repeating this process with over 500 children. Some kids immediately looked around and ate the first marshmallow—they couldn’t resist the temptation even for a moment. Others managed to wait for 7-8 minutes before giving in. But 30% of the children were able to control themselves and wait the full 20 minutes.

A decade later, Mischel conducted follow-up studies and reached out to some of the children to learn about their lives and progress. He noticed that those who had been able to wait at age four were now performing better in school.

Excited by this discovery, he tracked down 186 of the children who had participated in the original study and tested their performance on the SAT. The results surprised even him: the kids who had shown self-control at age four scored significantly higher than those who hadn’t.

The difference between a child who ate the marshmallow immediately and one who waited 20 minutes translated to a 210-point difference in their SAT scores. Additionally, those who had stronger self-control were better at social interactions. The children who had struggled with self-control were more likely to be sent out of class and were often labeled as bullies.

Over the years, Mischel continued to follow these children, gathering data. Forty years later, those with higher self-control were more likely to hold steady jobs, had better relationships with friends, and were even slimmer.

Can We Change Our Reality?

Ever since the original experiment, countless people have tried it with their own kids out of curiosity. But one of the more unsettling conclusions from this research is the idea that we might be born with certain traits—kids who naturally have self-control seem destined to succeed, while those who don’t might be stuck with a lifetime of struggle.

So, the big question is: Can we actually change this, or is it something we’re born with and can’t do anything about?

The Gemara in Niddah (16b) shares an interesting story. There’s an angel named Laila who oversees conception. This angel takes a drop (the embryo) and brings it before G-d, asking, “What will this child be? Strong or weak? Smart or foolish? Rich or poor?” The Midrash adds that the angel works at night, which is why he’s called Laila, meaning “night.” From this, it seems like a person’s fate is set before they’re even born.

But does that mean we’re locked into a predetermined destiny that can’t be changed?

There’s one area where Judaism is adamant that Heaven doesn’t decide for us, and that’s whether a person will be righteous or wicked. That choice is completely up to us. As the saying goes, “Everything is in the hands of Heaven except for the fear of Heaven.” In other words, the decisions we make about right and wrong, good and bad—those are entirely ours to control.

This week’s Torah portion tells us that the Torah is “not in Heaven,” nor is it “across the sea.” Instead, it says, “It’s very close to you—in your mouth and in your heart, so that you can do it” (Devarim 30:12-14). The message is clear: following the Torah and mitzvot isn’t out of reach; it’s something every one of us can do.

But let’s be real—sometimes, it feels difficult. That’s where the Tanya comes in. The book of Tanya serves as a guide to show us how living a life of Torah and mitzvot is truly possible for everyone.

The Alter Rebbe explains that the entire Tanya is based on this idea: fulfilling the Torah and mitzvot is not just “possible,” it’s actually very close to us—within our reach.

Now, it’s true that people are born with different tendencies. Some are naturally more spiritual, and they find it easier to connect to prayer and Torah study. Others might be more skeptical or have a harder time connecting. For example, women tend to have a more instinctive belief in G-d, while men often lean toward questioning and doubt. Or think about food: some people love eating and find it tough to fast on Yom Kippur, while others don’t think about food much and fasting comes more naturally to them.

But here’s where the Alter Rebbe makes an important point: no matter what our natural tendencies are, we all have control over three things—our thoughts (what’s in our heart), our words (what comes out of our mouth), and our actions (what we actually do). These are the areas where we have the power to grow, improve, and change. So while we might be born with certain traits, we’re not trapped by them. We have the ability to change our reality through our choices.

The Power to Control Even Your Thoughts

Every person has the ability to control their actions, even if it goes against their natural tendencies. No matter what traits they were born with, they have the power to choose their behavior. For example, even if someone is naturally lazy, they can force themselves to get up and help their spouse wash the dishes. This power of control doesn’t just apply to actions but also to speech. While it may be harder to control what we say than what we do, it’s still possible. Everyone has experienced saying something they regret, but with effort, we can choose our words more carefully.

Then there’s the matter of controlling our thoughts. It’s true that we can’t always control the thoughts that pop into our minds. But what we can control is what we do with those thoughts. We have the ability to decide whether to dwell on them, develop them, or shift our focus to something else. That’s something completely within our control.

The Rebbe often encouraged people to “Think good, and it will be good.” While this can sometimes be very challenging—especially when you’re worried about something—every time a troubling thought enters your mind, you have the power to push it aside and focus on something more positive. It’s not easy, but it’s definitely possible.

This concept applies even to what the Gemara says about a person being born “wise or foolish.” While it’s true that someone who’s naturally wise may find school easier, even someone who’s less gifted can succeed if they put in the effort. The angel’s determination before a person’s birth may indicate whether things will come easily or with more difficulty, but in the end, even someone born with less natural intelligence can become wise and learned if they work at it. The same goes for someone born without a natural talent for business—if they try hard enough, they can succeed too.

We all know people who wouldn’t have passed the “marshmallow test” yet still went on to achieve great things in life. Why? Because, as the Torah says, “It’s very close to you—in your mouth and in your heart, so that you can do it!”