Hypothetical QI

APPLAUSE AND CHEERING

Well, hello!

Hello, hello, hello, hello, hello, hello, hello, hello!

And welcome to QI,

where we bring you a television first -

a quiz show with no answers.

Tonight we depart from the certainties of everyday life

to explore the realm of hypothetical questions.

Or do we?

It's a job for only the very finest minds,

by which I mean the potential Johnny Vegas!

The possible Sandi Toksvig!

And the increasingly unlikely Alan Davies.

Now...

tonight is the 99th recording of QI

and to celebrate, we have with us the man who thought it all up in the first place.

He can dish it out, but let's see if he can take it, Mr John Lloyd!

They all have appropriately quizzical buzzers.

Sandi goes...

SANDI: "Um..."

Johnny goes...

-JOHNNY:

-"Hmm..."

John goes...

-JOHN:

-"Ooh, um..."

-And Alan goes...

-Sir, Sir! I know! Me, sir!

As if!

And let's open our minds now to the possibilities of question one.

What's the best way to weigh your own head?

LAUGHTER

Any thoughts?

Well, cut it off would obviously be the most accurate way.

Then someone else could weigh it, but you couldn't!

That would be the problem. The question was...

You introduced us and you normally introduce me last. It caught me out.

I was applauding myself!

Oh, bless!

Alan Davies!

And I was applauding myself insincerely.

That's what Soviet leaders do! Or chimpanzees.

-One or the other.

-Yeah.

Why would you want to weigh your own head?

It's a boys' thing. Imagine some poor woman married to a scientist.

She's at home, wormed the dog, fed the children, all sorted,

and her husband says, "Good news, dear. I've weighed my own head."

It may not seem like the most useful thing to do,

but it does employ interesting scientific ideas

on which we all depend.

Is it that thing that David Frost used to tell that joke for years?

"Do you want to lose 12lbs of unsightly fat?

"Cut off your head."

-Was that his joke?

-He used to tell that a lot.

What is one of the most famous ancient moments of scientific discovery?

-SANDI: It's the bath.

-Is it Archimedes?

Archimedes and the bath. What did Archimedes do and why...

Displaced. You could put your head in a bucket.

-Is that right?

-I've no idea.

-Join in.

-I was going to weigh myself, go to the swimming baths,

and bob and then get people to feed me until I sank.

Then come back out and weigh myself again.

Yep. That sounds much more scientific!

So by displacement of the water, you can tell...

Take a big bucket and fill it with water, and drop your head in.

Because water and the density of your head are about the same, you get a close approximation

by the amount of water that you displace.

-You can put apples in to make it fun.

-Bob for apples, yes.

And what did your head weigh when you tried this?

What would you say is the average weight? The University of Sydney weighs heads quite a lot.

-They have a pretty good average.

-By dunking them in buckets?

-They don't actually dunk them.

-Is it 12lbs?

-It's 4.5 to 5 kilos,

-which is...

-I've no idea.

2.2 kilos in a pound.

Not far off.

-2.2.

-It's about 12lbs.

-Yes, about 12 lbs. Well done.

I'll give you a point for 12lbs, John.

You may have negotiated us a point!

Surely you should give those points to David Frost who thought of 12lbs in the first place.

-He hadn't cut his head off, though.

-What if you get an air pocket in your ears?

-A pocket?

-You know, air pockets.

But the air cavities are cancelled out by...

Fingers out - you won't hear the answer.

APPLAUSE

You have bones that are denser than water and air pockets that are lighter.

Together, it does seem that the head averages about water.

So it's a good displacement test.

But there is a modern piece of technology that can do it to frightening degrees of accuracy.

-A laser or something.

-No, a CAT scan, a CT.

They can tell the density of every little tiniest part of the brain

and skull and all the rest of it and tot it up.

My dad's got heavy eyes.

-Has he, now?

-Yeah.

-Have you weighed his eyes?

-No, we've not,

but he's very fearful of leaning forwards.

Is he?

-Honestly!

-Do they crash through his glasses?

-He won't lean forwards.

-He thinks they'll come out!

-Are they on springs like those things you buy?

We got rid of novelty dad.

This is mental dad!

My grandfather had two glass eyes, and yet he could see.

What happened was, he sadly lost one eye. He wasn't careless, he was ill.

And he had a glass eye made, exactly like his other perfectly working blue Scandinavian eye.

Then he had one made that was bloodshot.

It was known as Grandpa's party eye.

He kept it in a box on the mantelpiece.

When he went out for the evening, he'd take out the blue one and put in the bloodshot one.

He'd say, "I'm going out now and I shan't be back till they match!"

Oh, that's brilliant!

Brilliant!

Fantastic.

-I assume...

-I thought he had two glass eyes like that!

-That would be silly!

-Did he have a hole at the back?

Was your granddad Nookie Bear?

Talking of heads, do you know anything about Sir Francis Drake? I don't mean Sir Francis Drake.

But as I've mentioned him, do you know anything about him?

LAUGHTER AND APPLAUSE

-Something to do with bowling.

-That's right.

He was in the navy!

Let's move on from Francis Drake. Thanks.

What do you know about Sir Walter Raleigh?

He invented the bicycle.

-His wife carried his head around in a bag for more than 30 years.

-Excellent.

-A velvet bag.

A red velvet bag, yes.

-Sir Walter was executed.

-I see why John had to invent this show for this kind of information!

You carried it around much as Lady Raleigh carried the head.

-It was on Buzzcocks last week.

-Was it?

-What sort of bag? Was it a sealed bag, a cool box?

-I don't know.

People did keep heads.

I bet it was a few years before anybody wanted to sit next to her at dinner!

-Lady Raleigh?

-Do you not think? "Oh, she's not going to bring the head, is she?"

Very fine. Don't know how we got there, but like many of the questions in tonight's show

there's no one correct answer, but dunking your head in a bucket is a good start.

If that has you scratching your head, when might you engage in paradoxical undressing?

-So you're undressing but you're actually dressing?

-No, it's not really paradoxical.

-Is it physics or mathematics?

-No.

-It's counter-intuitive undressing.

-Yes.

So taking your clothes off if Jeremy Clarkson asks you would be...

-Miaow!

-..would be silly.

It's taking your clothes off when taking your clothes off seems the worst idea you could have.

-Is it some effect of hypothermia? Some mental...

-Exactly what it is.

-..thing it does to you.

-It may be mental, it may be physical. It's not understood.

-Oh, that is very unpleasant!

Let's go back to the previous picture!

It's one of the peculiar side-effects of hypothermia.

When you're actually dying of cold, almost the last thing you do, very commonly, not always,

is take all your clothes off.

People think it may be a delusional thing.

But also your blood vessels near your skin tend to just give up and open,

and maybe people feel very hot. Because you never survive past that stage, you can't ask someone

why they did it. But it is a common thing for people to do and they're freezing.

I went in freezing water once. I screamed and swam about and I went shocking, livid pink and felt hot.

I was perhaps seconds from death!

Maybe you were!

-Maybe you're one of the few who survived it!

-Yeah.

What sort of temperature do you think would start you on the road to hypothermia? Body temperature,

not outside temperature.

What's the temperature in here?

I'd say pretty quickly.

Don't think it would have to drop much. Four or five degrees below normal?

That's right. 35 degrees Celsius. Once your temperature gets below that.

Interestingly, in the coldest cities in the world, hypothermia is very rare.

Much more common in Britain where it doesn't get very cold.

There's a very remarkable Briton called Lewis Pugh. Have you heard of Lewis Pugh?

He's a man who's able to control his own body temperature.

He does endurance cold swimming. He's the only person known to science who can do what he can do.

He can swim in cold conditions

unlike anybody else.

He's able to raise his body temperature at will.

It's completely startling.

-A superhero!

-He can stop himself shivering. He's an incredible figure.

We contacted him. He said that he thought he could do this...

He said he's not coming in here cos it's freezing!

He thought he could do this because he had trained himself over years and years

to do these endurance swims in incredibly cold waters.

His body saw it coming and prepared for it. That was his explanation.

Cold water has a bad effect on a boy. He looks good there,

but I bet he doesn't fill his swimming trunks when he gets out!

Actually, this is not that unusual.

We went on this yoga thing recently.

The yoga teacher was saying that these sadhus in India

can do this body raising thing.

They did some scientific experiments in the States

where they shipped in these guys, wiry guys with turbans on,

and they put wet towels on them. The turn up their own body temperature

and literally steam the towels dry, in a few minutes.

-Extraordinary.

-SANDI: Can you hire these people?

It's a good act if they can get on Britain's Got Talent!

That would be good. "What are you going to do?" "I'm going to dry this wet towel!"

You could do patterns on wet towels with your hands. "It's art!"

Paradoxically, the last thing people do when freezing to death is take their clothes off.

Now it's time for a round of quick-fire hypotheticals!

So... All you have to do is tell me the first thing that comes into your head,

quick-fire hypothetical questions.

Let's say you found a fallen tree in the forest.

Obviously it fell down before you arrived.

-But did it make a sound as it fell?

-Ooh, um...

-No.

No-one's going to say yes, are they?

Yes, you're right.

-Do you know where the question comes from?

-It's a famous...

-Bishop Berkeley.

-Yes.

A philosophical question.

If there's no-one to hear a sound, is there a sound?

It depends what you mean by sound.

There isn't because sound is the vibration of the ear drum.

-Y... Is it?

-If there's no-one to hear it.

-It depends, though.

Part of the definition of sound is there has to be a recipient.

Something makes the noise, the transmission of it, and reception of it.

-If there's no reception of the noise, maybe it doesn't exist.

-Other things are vibrating.

But whether that vibration counts as a sound or not is a moot point.

-Is the forest ever empty?

-There isn't any sound if there's no-one to hear it.

-It's a mooty point.

-There's the speed of sound and if it's only what happens in the ear,

how do you get that speed between that and your ear?

LAUGHTER

No, I'm...

APPLAUSE

Maybe by the time that tree's fallen and you get there, that sound is half way round the world.

And making someone else very nervous.

"Aghh!"

-Stephen, are you sure about this?

-Well,

no-one is sure. That's the point. That's why it's hypothetical.

To a semanticist or a neurologist, they may say sound is that.

A physicist would say the propagation of sound waves is sound.

Whether or not there is an ear to vibrate, it is a sound wave.

-If it's a sound wave...

-I disagree that they are sound waves, because...

You may disagree. You're welcome to!

A vibration can only become a sound wave when there's an ear to receive it.

It's rather like - do you remember we talked... A thing that astonished me.

Did you know that light is invisible?

In a dark vacuum, if you shoot a beam of light across the eyeballs,

-you can't see it because you can only see...

-But what about sound?

-..what light hits.

It's the same thing. People say but that's a stupid answer

because the definition of light is something that goes into your eye and is then received.

Until it does that, it's not light.

But we have all kinds of things like not ears, for example.

Are you saying it's not sound if it registers on a recording device that is left there?

It bends the needle of a recording device. Does the machine not hear?

Is it not a sound wave that is causing the machine to register?

-Yes, but Bishop Berkeley...

-I'm talking about you, not Bishop Berkeley!

The point is, it's not as simple to just say yes or no.

Go on, Stephen! Go on! Go on!

You've got him!

It's a good question. We would have forfeited somebody who said yes as much as somebody who said no.

-I thought you said there was no right answer.

-Yes, that's why it's a good question.

-There is no right answer. So your yes and your no...

-Whatever I'd said would have been...

-I'm afraid so.

What if the tree fell and there was no-one there to see it, it should still be upright.

-Very true.

-It's like the illusion...

-You're right.

Anyway, Alan, are you keeping well?

Until that tree fell over - there was a hell of a bang!

It's a quick-fire hypothetical, don't forget, so we move on. OK.

-You're talking to an England...

-I can't do quick-fire!

-Yes, you can, darling.

If a quick-fire hypothetical round takes a really long time, is it still quick-fire?

Good point! We'll find out!

Very good point. You're talking to an alien in a distant galaxy

-by radio. How could you explain which is right and which is left?

-Breaker breaker.

That would do it, would it? Just by saying "Breaker breaker", he would know...

Well, it depends what height mast he had, but yeah, it should...

-It's nice...

-There's got to be alien truckers!

-Fair point.

-They must run freight.

-I'll tell him what's left and right and if he's got a smokey on his arse.

-Right. Right.

-Hypothetically, are we looking at any common reference point?

-That is the point. You can't...

-"Can you see Mars. Yeah? We're on the right."

"Can you see the spot on Jupiter?"

You'd need something to reference.

Yes. Semantically, there is no explanation for left or right

without reference to a physical world that someone can identify.

You can't explain it just by language. That's the point.

Well, if they visited in a ship, you could give them a temporary tattoo.

Yes, you could do that. Which is why we framed the question so specifically, saying...

-Oh, talking on a radio.

-..tattoos were out.

Ah, sorry. I'm just a problem solver by nature!

-No, it's good.

-Anyway, they may not have... We always draw them in that shape, two eyes.

What if they've got four eyes and eight arms and don't have one or two...

They may not be symmetrical in any way.

-They might have other dimensions in all sorts.

-They might have 19 versions of left.

Imagine that on a Sat Nav!

-Left-ish!

-Not that one, not that one - that one!

-L-l-l-l-l-left!

-Why do we always...

-Why do we always draw them like that?

-I've no idea.

They might have one eye in the middle.

The ones that probed me looked nothing like that!

Do you have a little thing in your head as a mnemonic when you forget left and right?

-Do you do that?

-I walk into traffic.

Sorts it out straightaway!

-Do you have a problem?

-No, I don't,

but if I have to think, I remember the thumb I used to suck as a very small child.

-That's my right hand. No-one else have this?

-This is like a therapy session!

There's a wonderful story about a famous ocean liner captain.

He had a silver box that he kept in his pocket.

Every time before they came into port, he'd open the box, look, then put it away.

After many years service, he finally died and his second in command said, "I must look at this box."

He opened the box and it said, "Port - left, starboard - right."

Brilliant.

That's the point, though, you can't really find out.

Now, a lorry-load of birds are being weighed on a weighbridge.

At some moment, all the birds simultaneously rise off their perches and flap in the air.

-So they're all alive.

-Yeah. Does the lorry weigh less...

-Yes.

-..when they rise up in the air?

-Yes.

-No.

-Got a yes and no.

-So they're not in contact with the actual...

So it would weigh less.

-Is it sealed, the lorry?

-It's closed, it's got a tailgate. It's locked up.

-They're inside the lorry.

-Wouldn't there be pressure from the air?

-Yes.

-It's not... They don't. It weighs the same.

It's something to do with, something very similar to, if you weigh yourself

then go and do a number two and weigh yourself again,

-you don't lose the weight of the number two.

-Ah.

LAUGHTER

There we're in a slightly different territory!

If you will do it on the scales!

You're right. The answer is not to poo on the scales!

-No...

-Leave the scales, do the number two and come back to the scales!

-You don't lose it when you...

-The money I've wasted on enemas!

I've argued this. It weighs the same and I can't remember the reason why!

-I know this.

-So they all lift off at the same time.

It is weight. It's a bird/lorry system.

-I know it's weird.

-Is it sealed? Is it to do with it being sealed?

If you're carrying a bowling ball and you're on the scales,

-then you throw the ball in the air, it'll kill you.

-You're part of something when you're inside it.

-Because it's sealed...

-The air's moving.

-..you and the Earth have created that weight.

So wherever the birds are within that, it weighs the same.

-Interestingly - you're absolutely right...

-Don't pass it off that easily!

The interesting question is if it's an open-top lorry

and they jump up like that and jump up slightly higher,

then they're out of the system, no longer part of the lorry/bird system.

Then it would be lighter.

Well done, everybody. It's time to move on from our hypotheticals.

That was very quick!

So, hypothetical problems are the curse of the practical man.

Hypothetically, what would happen if Schrodinger put a Siamese cat in the fridge?

In the fridge?

-He wouldn't know if it was alive or dead.

-Good.

You're referring to Schrodinger's Cat, which is?

-I learned about this on Horizon.

-Very good.

You don't know until you open the door whether the cat is alive or dead.

That is the quantum paradox of Schrodinger's Cat.

You're putting a Siamese cat in the fridge?

What is the question?

What would happen to the cat?

It would get cold. What would happen to the fridge? Less milk left, probably!

It would eat all the tuna melts!

The tuna melts would go, yes.

-But something quite extraordinary would happen.

-It would turn into an ordinary cat.

-Well, almost! Almost!

-It would turn into a dog.

-It's not that remarkable.

-In seconds.

"Miaow!" "Woof!"

Let's have a look at a Siamese cat and see what's particular about it.

White body, black face.

You'd get a black body and a white face!

It's got a white body and a black tail and black ears and black mouth and black socks.

In other words, black extremities.

-What is particular about the extremities of any mammal?

-They're cold.

-So if you put the whole animal in a fridge...

-It goes black!

-It goes black, Johnny. You're absolutely right.

-That's death.

That's what happens.

Its fur has this peculiar colorant that keeps it pale in warm blood heat.

But a small difference in temperature down,

and it will lose the white or gain the black, whichever way you look at it.

-When you take it out, does it go pale again?

-Yes, back to normal.

It would be worth trying, just for the laugh.

I don't like cats very much.

I'm sorry. So many cats, so few recipes! I just think...

LAUGHTER

I just think it sounds like fun.

You can also try it on a Himalayan rabbit. They have the same issue.

-Please don't try this at home!

-No.

Do you know about buttered cat?

There's a recipe straightaway!

-Buttered cat syndrome.

-Delicious!

You put butter on their paws to stop them going home if you've moved.

This is a paradox. There are two laws. If you have buttered toast and drop it, what happens?

-It falls butter side up.

-Butter side down. If you drop a cat, what happens?

-It falls butter side up.

-No.

-It falls...

-It lands on its feet.

So if you were to put some toast with the butter side up and attach it to a cat,

what would happen is the cat would drop and it would have to revolve forever!

-Because...

-Then you've got an act!

-..the two laws would compete and it would be in balance!

Would it work with margarine?

I don't know. I think the law doesn't state that the margarine falls downwards.

I can't believe it's not butter!

What if it...

What if it was margarine but the cat believed it was butter?

Ah, the placebo effect! Exactly.

Brilliant! Brilliant! You've all got the point.

-What if cats discovered this and started to migrate?

-Where would they go?

I don't know! It's just a cat with a piece of toast! I'm not going to dictate where...

Let's just keep it from them. So, yes,

if you put a Siamese cat in the fridge for long enough,

and it would have to be quite a long time, probably weeks, it would go black.

And you mustn't!

But after that voyage through a land where there are no wrong answers,

we come to one where there is rarely a right one.

To the realm of general ignorance. Fingers on buzzers

and stop me when you know what I'm talking about.

It's an insectivorous mammal, it's found all round the world.

It's active at night,

it's almost totally blind.

A bat?

No. You were so right until the last part.

They're not blind.

-An anteater?

-Not an anteater, no.

-A mole?

-It's insectivorous so it could eat ants.

Is it a mole?

-Mole is the right answer.

-I said mole!

-Did you? Sorry!

-I just said mole!

-Did he say mole, ladies and gentlemen?

-Yes!

No, because sound is just a thing and it didn't travel!

Yeah, if you didn't hear me say mole, then I didn't say mole!

-So you need the points, I suspect, Alan.

-I probably do.

There are about 1,100 different species of bat, and none of them is sightless. Not one.

-Is the mole completely sightless?

-It can just distinguish between light and dark.

-But essentially it's blind.

-It can tell if the telly's on or off!

-Yes, if you like!

It can't tell if it's on standby!

-How many moles are there in Ireland?

-None.

-Right.

-There are none.

-Why?

-They're very pally with the snakes.

Glaciation and the separation of Ireland, they never got back.

-It was an island.

-They could tunnel!

-Like snakes.

-Tunnel!

-If any animal can tunnel, it's a mole.

-Oh, sweet!

-You say sweet,

but almost certainly all photos of moles that are taken are of dead moles.

-Because they fluff them up.

-That's terrible!

-Their eyes are always black slits.

-It's like those greeting cards.

A cat on a deckchair, or a cat and a mouse.

They're all dead.

I fear so. Yes, moles are as blind as the proverbial bat.

Bats, perversely, aren't. Finally, the ultimate hypothetical question.

Which came first, the chicken or the egg?

Uh...

-Chicken.

-No!

-The egg.

-Egg is the right answer, yes.

There's that old joke about the chicken and egg have just made love.

They're having a post-coital cigarette.

Chicken says to the egg, well, that answers that old question!

As the scientist JBS Haldane said, anyone who can ask that question hasn't understood evolution.

A chicken evolved from reptiles that laid eggs themselves.

So the eggs were coming well before there was a chicken.

So it did, indeed, come first, the egg.

What's the longest recorded flight by a chicken, in time terms, not distance.

13 seconds? Something like that?

Yes.

-Yes, it is 13 seconds!

-Is it really?

LAUGHTER AND APPLAUSE

I don't claim that's true, but that is one of the oldest internet pieces of trivia I know,

apart from a duck's quack does not echo and no-one knows why!

-We know that isn't true.

-No.

So, anyway, birds evolved from egg-laying reptiles

so there were definitely eggs before there were chickens.

We emerge older but no wiser at the end of the only quiz to offer no answers, just more questions!

But had there been answers, let's see who would hypothetically have won.

Our theoretical winner tonight with two points is Sandi Toksvig!

Notionally in second place is elf-master general, John Lloyd, with minus one!

On paper in third place with a creditable minus seven, Johnny Vegas!

Finally, proving that it's all academic and a dream,

with minus 27, Alan Davies!

So, that's all from this hypothetical edition of QI.

Or is it? Yes, it is.

So it's good night from Sandi, Johnny, John, Alan and me - good night!

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