New R-S-P-R-A-C-H-E or Stalker Verius Kroen.

Everybody knows that effort matters.

What was revelatory to me was how much it mattered.

This is Hidden Brain, I'm Shankar Vedantin.

What is it that makes extraordinary people successful?

Is it talent, genius, luck?

Or is Angela Duckworth suggests, is it grit?

There is a fluency and an ease with which true mastery and expertise always expresses itself,

whether it be in writing, whether it be in a mathematical proof.

But I think the question is, where does that fluency and mastery come from?

Today on Hidden Brain, we explore this quality that Angela says is responsible

for so much excellence in achievement.

And then we ask, does grit also have a downside?

Sometimes people with high grit might not do the logical, rational thing

and because their grit compels them to keep going.

Angela Duckworth is a psychology professor at the University of Pennsylvania.

She first became interested in grit while working as a math teacher

for middle school and high school students.

Angela told me that when she started teaching,

she noticed right away which kids were the quickest learners,

the most naturally talented you might say.

These were the kids who when she explained a concept once,

...