David Spiegelhalter

And it's shown, people have shown it again and again. So it works. and you can prove it mathematically fairly easily, but it is something that doesn't correspond to our intuition. But there are other things that go the other way. That's something that we think is, whoa, that's surprising that happens so often. The other thing that actually happens is surprisingly rare is shuffling a pack of cards.

Now, if I shuffle a pack of cards properly and give it a good shuffle, I could be absolutely confident, bet you all the money in the world, that nobody in the entire history of humanity has ever had the cards in that order before. And then I can shuffle them again into a good shuffle, and I say nobody in the entire history of humanity has ever had the cards in that order before.

Now, if I shuffle a pack of cards properly and give it a good shuffle, I could be absolutely confident, bet you all the money in the world, that nobody in the entire history of humanity has ever had the cards in that order before. And then I can shuffle them again into a good shuffle, and I say nobody in the entire history of humanity has ever had the cards in that order before.

Now, if I shuffle a pack of cards properly and give it a good shuffle, I could be absolutely confident, bet you all the money in the world, that nobody in the entire history of humanity has ever had the cards in that order before. And then I can shuffle them again into a good shuffle, and I say nobody in the entire history of humanity has ever had the cards in that order before.

And not just now, it's unbelievably unlikely that anyone ever And no two people in the whole history of humanity have ever had a pack of cards in the same order after a good shuffle. And people find that really difficult to believe because it's not intuitive just how many shuffles there are. And, you know, you can do the sums.

And not just now, it's unbelievably unlikely that anyone ever And no two people in the whole history of humanity have ever had a pack of cards in the same order after a good shuffle. And people find that really difficult to believe because it's not intuitive just how many shuffles there are. And, you know, you can do the sums.

And not just now, it's unbelievably unlikely that anyone ever And no two people in the whole history of humanity have ever had a pack of cards in the same order after a good shuffle. And people find that really difficult to believe because it's not intuitive just how many shuffles there are. And, you know, you can do the sums.

It's sort of 52 for the first card and 51 choices for the second card and 50 for the third card. And you multiply all those numbers up together and you get a very good number. In fact, the number is about the same as the number of atoms in our galaxy. It's, you know, it's got 78 zeros, I think, beyond it. You know, it's an unbelievably massive number. And that's not intuitive at all.

It's sort of 52 for the first card and 51 choices for the second card and 50 for the third card. And you multiply all those numbers up together and you get a very good number. In fact, the number is about the same as the number of atoms in our galaxy. It's, you know, it's got 78 zeros, I think, beyond it. You know, it's an unbelievably massive number. And that's not intuitive at all.

It's sort of 52 for the first card and 51 choices for the second card and 50 for the third card. And you multiply all those numbers up together and you get a very good number. In fact, the number is about the same as the number of atoms in our galaxy. It's, you know, it's got 78 zeros, I think, beyond it. You know, it's an unbelievably massive number. And that's not intuitive at all.

Yep, as many atoms as there are in the whole galaxy. And so the shuffle you come up with after a good shuffle, nobody will ever have done before. You can be almost certain of it. You can't prove it, of course. It's not logically true. But statistically, it is just unbelievably unlikely.

Yep, as many atoms as there are in the whole galaxy. And so the shuffle you come up with after a good shuffle, nobody will ever have done before. You can be almost certain of it. You can't prove it, of course. It's not logically true. But statistically, it is just unbelievably unlikely.

Yep, as many atoms as there are in the whole galaxy. And so the shuffle you come up with after a good shuffle, nobody will ever have done before. You can be almost certain of it. You can't prove it, of course. It's not logically true. But statistically, it is just unbelievably unlikely.

Yeah, yeah, it is quite surprising.

Yeah, yeah, it is quite surprising.

Yeah, yeah, it is quite surprising.

How would you ever know that? Yeah, how would you prove it? That's true. It is difficult because you can't prove it. You can't look at every snowflake. I don't know every shuffle that's ever been done. But you can do the sums and you can work out just how incredibly unlikely a match would be.

How would you ever know that? Yeah, how would you prove it? That's true. It is difficult because you can't prove it. You can't look at every snowflake. I don't know every shuffle that's ever been done. But you can do the sums and you can work out just how incredibly unlikely a match would be.

How would you ever know that? Yeah, how would you prove it? That's true. It is difficult because you can't prove it. You can't look at every snowflake. I don't know every shuffle that's ever been done. But you can do the sums and you can work out just how incredibly unlikely a match would be.

Yeah. Taleb uses the frame Black Swan, which is essentially a really completely unpredictable event that occurs and then people find an excuse for it. Perfect Storm is different. It's just a very extreme example of something fairly familiar. And, you know, the story I use is about this boat, the MV Derbyshire, which is twice the size of the Titanic, and disappeared without trace in 1974.