You're listening to TED Talks Daily. I'm Elise Hugh. Today, writer Stephen Johnson presents us an interesting thought experiment. What if we had to write a newspaper headline? For the entire century, what would be the big headline? In his 2021 talk from the Ted Monterey stage,

he offers what he thinks is the biggest story and why.

This was one of my favorite talks from the whole conference.

I still think about it a lot.

And if you want to dive deeper on this stuff,

Stevens got a book and TV series

and coming soon a new podcast all around this topic.

It's called Extra Life.

There's a classic thought experiment that's designed to trick your brain into thinking long-term

and getting out of the daily news cycle.

And it goes like this.

If a newspaper came out once a century, what would the front-page banner headline be?

Be defeated the Nazis or landed on the moon or built the Internet?

I would argue that it would be the story of a single number, maybe the most elemental measure of progress that we have,

life expectancy at birth, the length of time that the average person can expect to live

in a given place at a given time.

A hundred years ago, as best as we can measure, the average global life expectancy stood somewhere in the mid-30s.

Today, it's just over 70.

So in one century, we doubled global life expectancy.

This is an extraordinary achievement.

And you'll sometimes hear people say that life expectancy

and this kind of progress is actually just a statistical illusion,

...