Hello and welcome to More or Less on the BBC World Service with me, Tim Halford.

Now, here are More or Less.

We like to think of ourselves as rational people.

We're children of the Enlightenment, disciples of statistics, surely the very embodiment

of considered thought, much like our loyal listeners.

Now, coincidence then that many of the More or Less team, and I can certainly speak for

myself, grew up admiring that Paragon of Reason and Numeracy, Star Trek's Mr Spock.

All I know is logic.

In my opinion, we'll be lucky if we can repair this ship and get away in time.

I prefer the concrete, the graspable, the provable.

You'd make a splendid computer, Mr Spock.

We'll return to Mr Spock in his predictions later, but suffice to say, being a rational

person is not always as simple as being able to crunch numbers or apply logic, as our

guest today well knows.

Julia Galeff is author of The Scout Mindset, a book about how our attempts to be rational

are often clouded or derailed by our human impulses, and the ways we can avoid these traps.

I ask Julia to tell us what the scout mindset means.

So that's my metaphor for wanting to see things as accurately and objectively as possible,

even when the truth is not convenient or pleasant or maybe not so flattering to your preconceived

notions or biases.

I mean, don't we always want to know the truth?

What's the counter example?

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