This is NPR's Life Kit.

I'm Rose Evelith, and I make a podcast called Flash Forward, which is all about the future.

I spend most of my time thinking about what might happen next and how to shape futures that we actually want to live in.

And one of the coolest but also hardest things about thinking about the future is that you have to be willing to reconsider pretty much everything.

You have to be pretty open-minded about possibilities.

And while it might not feel like it day-to-day, human history actually is full of examples of people changing their minds for the better.

In the middle ages, there was something called trial by ordeal. You know, you would throw somebody you thought was guilty into the water.

This is Maserine Benaji, a professor of social ethics at Harvard University.

And she says that in medieval Europe, people would actually be like, hey, we think this person committed a crime.

Let's toss him in a lake and see if we're right.

And if they rose to the top by swimming, then surely they were guilty. And if they sunk to the bottom and died there, then clearly they were innocent.

This is how people adjudicated guilt and innocence.

And today, to us, it seems completely bizarre.

So why is that? It's because we had an open mind. And we changed a little at a time.

There are definitely things today that future people will look back on the way we look at trial by ordeal and go,

can you believe they thought that? In other words, to bring in a better future, you have to be open-minded.

Open to the idea that maybe what we have now isn't something we want to keep.

That maybe we should change. And in this episode of LifeKit, we are going to teach you how.

If you look up lists of best personality traits in people, open-mindedness is pretty much always on them.

Next to things like generosity and integrity and kindness. But if we're being honest,

which incidentally is also on all of those lists of positive personality traits,

we're not always as open-minded as we might like to be.

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