This is the illusionist in which I, Helen's ultimate, make language take a polygraph test.

Coming up in today's show, trust.

You can trust me.

What can you?

I'm just a person who lives in your head.

On with the show.

Do you know, I thought it was going to be really easy to define trust.

So my definition of trust is trust is a confident relationship with the unknown.

And the reason why I ended up with that definition, which took about five years to get to confidence

is really at the heart of trust.

But if you know the outcome of something, if there is no risk, you don't actually need trust.

So what I was trying to pair it with is something unknown, the uncertainty piece.

So it's this idea that we are placing our faith in someone or something or a system

where you don't actually know the outcome and how it's going to work.

When you think of it like that, it's like this alchemy of fears and hopes and desires.

So it's got the high and the low.

And that's what trust is made up of.

It's this friction between these two things.

My name is Rachel Boltzmann.

I am an expert on trust and the author of a book called Who Can You Trust?

Rachel has been studying trust for the past decade.

The word has been in the English language for at least 800 years.

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