There's been a controversy about whether it replicates.

Some of the replications have shown that if you have a lower socioeconomic status, you struggle with the Marshmallow Test.

I want to talk to you as well about something you mentioned earlier, which was this idea of doing difficult things.

That appears to be one of the key correlating factors with success in life, your ability to choose discomfort.

I want to be really clear to say it's a skill.

It's not just a personality trait.

Yeah, some people are born with a little extra reserve of willpower, or they have the discipline, or the grit, or the resilience, and it comes naturally to them.

But this is very much a learned skill, and I think the clearest demonstration of this for me is the Marshmallow Test, which has been wildly misunderstood in the last few years.

So you're familiar probably with the classic demonstration that Walter Mischel did with his colleagues, where you take four-year-olds, put a marshmallow in front of them, and you say, you can have one now, but if you're willing to wait until I come back, then you can have two.

And then the original finding is that the longer you can delay gratification, if a kid can wait 10 or 15 minutes for the extra marshmallow, a decade later, the better grades they get in school, there are all kinds of benefits of this delay gratification skill.

Well, in psychology recently, there's been a controversy about whether it replicates, and some of the replications have shown that if you have a lower socioeconomic status, you struggle with the Marshmallow Test.

It's really disappointing, but it's not at all surprising, and in fact, that was part of the original research, is if you grew up in a world of scarcity, you could not afford to wait for the second marshmallow.

It might never come.

You didn't know if you could trust the research team to come in and bring you one, and so you didn't have the chance to practice that skill and learn the habit.

But what's really interesting is if you watch kids who crush the Marshmallow Test, it's more skill power than willpower.

What they have are simple strategies that actually make the temptation less tempting.

You see one kid will actually sit on...

He sits on his hands so that he's...

It's a little slower for him to reach out to the marshmallow.

Another covers her eyes so she doesn't have to look at it.

And then there's one kid who actually smushes it into a ball and starts bouncing it, so you don't want to eat that anymore.

And this is why I say it's a set of skills, not just a matter of will, because if you have techniques for making discomfort less uncomfortable, then you are willing to go into many situations where you're a little bit out of your depth and say, yeah, this might be awkward, this might be embarrassing, but I'm going to learn something.

And I guess, you know, for me, that was public speaking.

You touched on giving TED Talks earlier.

I would have never dreamed of standing in a red circle.

I had no business whatsoever giving a TED Talk.

I'm an introvert.

I'm extremely shy.

I was terrified of public speaking.

And in one of my first lectures, a student wrote in feedback afterward that I was so nervous I was causing them to physically shake in their seats.

And the only way for me to get over that was to put myself continually in that situation and get used to the discomfort.