The Power (and Limitations) of Self-Belief

In 1959, a surgeon named Leonard Cobb called bullshit. At the time, the most common procedure to help people with chest pain caused by heart disease was something called “internal mammary artery ligation,” where basically, they would intentionally close one of the main arteries near the heart so that the blood flow would push other arteries wide open. Patients at the time reported that this helped—they felt less chest pain, they had more energy, they could go back to their hamburgers and soda in peace.

But then they still died of heart attacks later. Cobb noticed this and felt that something was terribly wrong with this procedure. The problem was, he couldn’t really prove it. So, in 1959, he did something drastic.

Cobb took roughly 40 patients complaining of chest pain and shortness of breath. Half of them he gave the ligation procedure. The other half, he just put them to sleep, cut their chest open and then immediately stitched them back up, doing nothing. He gave them what’s now known as a “sham surgery.”

Afterward, 73% of the people who received the ligation procedure reported feeling better. But of the “sham surgery” group, 80% also reported feeling better. 

These results were shocking. Cobb’s famous “sham surgery” study was not only the nail in the coffin for the ligation procedure, but it opened people’s eyes about the potential power of the mind—that simply telling people they had surgery could give people the same results of actually giving them surgery. 

In medicine, the placebo effect was well known. It was well documented that roughly 35% of patients will report feeling better when given fake medicine. In fact, the placebo effect was so well understood in medicine that in the 18th and 19th centuries, giving out fake medicine was pretty much all doctors did, because in most cases, no real medicine had been invented yet.

But Cobb’s sham surgeries went way beyond prescribing sugar pills or telling people to gargle their urine. This was convincing people that they were to have a major surgical procedure… and then not doing it. 

So-called “sham surgeries” are highly controversial, but their effects have gone on and been replicated many times. People with meniscus tears have reported feeling no more pain after fake surgeries. People with herniated discs in their back have reported the same. A 2014 review found that fake surgeries are just as effective as real surgeries in roughly half of the procedures studied. That’s fucking crazy.

And, even crazier: the more invasive and dangerous the procedure they pretend to give you, the more likely you are to believe it worked.

This is the moment in most personal development content where I spew platitudes about, “BELIEVE IT AND IT WILL BE” or “MANIFEST YOUR DESTINY” or whatever. Basically, we all get our nipples hard at the idea that all it takes to achieve something is to believe it.

But there’s a catch. The placebo effect—i.e., the mind’s ability to manifest its own reality—actually appears to be limited to a few domains, one of them being the perception of pain. Whether it’s a meniscus tear or a migraine, a doctor giving you something fake seems to work pretty well at convincing you that you’re not in pain anymore. But when it comes to more complicated conditions such as genetic disorders or a deep depression, the placebo effect appears to disappear almost entirely.

In other words: the mind is powerful, but not all powerful. 

You see the same limitations of belief in other domains, as well. People who believe they will do well on a test tend to do better on tests. Or people who believe they will survive cancer are more likely to survive cancer. But last time I checked, people who believed they could fly are still stuck on the ground.

The simplest explanation for all of this is that there are a number of psychological feedback loops that involve the mind’s expectations and beliefs. You see the needle coming for your arm, you expect it to hurt, so it hurts. Whereas if you are distracted and talking to someone and you get poked by something sharp, half the time you don’t even notice until you’re already bleeding everywhere.

Pain is largely determined by the mind’s expectation of pain. Remove the expectation and you can often remove the pain. Add expectation (i.e., tell yourself that “words are violence” for instance) and you will experience pain where none is necessary.

Our beliefs are part of a number of systems within our lives. If we believe that people will hate us, then we are more likely to behave in ways that make people hate us, thus justifying the belief. If we believe we will do well on a test, we are more likely to feel motivated and engaged on that test, thus causing us to do well.

It’s tempting to put all of the credit or blame on our beliefs. But our beliefs are merely one link in the chain of experience, not experience itself.

In the self-help world, you often hear the term “limiting beliefs”: beliefs that prevent you from achieving some goal or experience you desire. Well, there are also limits to beliefs: boundaries where our expectations bump up against reality. 

It’s best to recognize both.