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  • (Music)

  • [Ted N' Ed's Carnival; open daily - all day long; Yew Chube Common - Entrance off the Google highway]

  • [John Lloyd's Inventory of the Invisible]

  • [Adapted from a TEDTalk given by John Lloyd in 2009]

  • Now our next speaker has spent his whole career eliciting that sense of wonder.

  • Please welcome John Lloyd. (Applause)

  • Question is: what is invisible?

  • There's more of it than you think, actually.

  • Everything, I would say -- everything that matters --

  • Except every thing, and except matter.

  • We can see matter

  • but we can't see what's the matter.

  • We can see the stars and the planets but we can't see what holds them apart,

  • or what draws them together.

  • With matter as with people, we see only the skin of things,

  • we can't see into the engine room, we can't see what makes people tick,

  • at least not without difficulty,

  • and the closer we look at anything,

  • the more it disappears.

  • In fact, if you look really closely at stuff, if you look at the basic substructure of matter,

  • there isn't anything there. Electrons disappear in a kind of fuzz, and there is only energy.

  • One of the interesting things about invisibility is the things that we can's see,

  • we also can't understand.

  • Gravity is one thing that we can't see, and which we don't understand.

  • It's the least understood of all the four fundamental forces,

  • and the weakest, and nobody really knows what it is or why it's there.

  • For what it's worth, Sir Isaac Newton, the greatest scientist who ever lived,

  • he thought Jesus came to earth specifically to operate the levers of gravity.

  • That's what he thought he was there for.

  • So, bright guy, could be wrong on that one, I don't know. (Laughter)

  • Consciousness. I see all your faces; I've no idea what any of you are thinking.

  • Isn't that amazing? Isn't it incredible that we can't read each other's minds,

  • when we can touch each other, taste each other, perhaps, if we get close enough, but we can't read each other's minds.

  • I find that quite astonishing.

  • In the Sufi faith, this great Middle Eastern religion which some claim is the root of all religions,

  • Sufi masters are all telepaths, so they say,

  • but their main exercise of telepathy is to send out powerful signals to the rest of us that it doesn't exist.

  • So that's why we don't think it exists; the Sufi masters working on us.

  • In the question of consciousness and artificial intelligence,

  • artificial intelligence has really, like the study of consciousness,

  • gotten nowhere, we have no idea how consciousness works.

  • Not only have they not created artificial intelligence,

  • they haven't yet created artificial stupidity.

  • The laws of physics: invisible, eternal, omnipresent, all powerful.

  • Remind you of anyone?

  • Interesting. I'm, as you can guess, not a materialist, I'm an immaterialist.

  • And I find a very useful new word -- ignostic. Okay? I'm an ignostic, [God?]

  • I refuse to be drawn on the question on whether God exists

  • until somebody properly defines the terms.

  • Another thing we can't see is the human genome.

  • And this is increasingly peculiar, because about 20 years ago

  • when they started delving into the genome, they thought it would probably contain

  • around 100 thousand genes. Every year since,

  • it's been revised downwards. We now think there are likely to be just over 20 thousand genes

  • in the human genome.

  • This is extraordinary, because rice -- get this --

  • rice is known to have 38 thousand genes.

  • Potatoes -- potatoes have 48 chromosomes, two more than people,

  • and the same as a gorilla. (Laughter)

  • You can't see these things, but they are very strange.

  • The stars by day, I always think that's fascinating.

  • The universe disappears. The more light there is, the less you can see.

  • Time. Nobody can see time.

  • I don't know if you know this. Modern physicists -- there's a big movement in modern physics

  • to decide that time doesn't really exist, because it's too inconvenient for the figures.

  • It's much easier if it's not really there.

  • You can't see the future, obviously,

  • and you can't see the past, except in your memory.

  • One of the interesting things about the past is you particularly can't see --

  • my son asked me this the other day, he said Dad, can you remember what I was like when I was two?

  • And I said yes. He said, why can't I?

  • Isn't that extraordinary? You cannot remember what happened to you earlier than the age of two or three.

  • Which is great news for psychoanalysts, because otherwise they'd be out of a job.

  • Because that's where all the stuff happens [laughter]

  • that makes you who you are.

  • Another thing you can't see is the grid on which we hang.

  • This is fascinating. You probably know, some of you, that cells are continually renewed.

  • Skin flakes off, hairs grow, nails, that kind of stuff --

  • but every cell in your body is replaced at some point.

  • Taste buds, every 10 days or so.

  • Livers and internal organs take a bit longer.

  • Spine takes several years.

  • But at the end of seven years, not one cell in your body

  • remains from what was there seven years ago.

  • The question is: who then are we? What are we? What is this thing that we hang on?

  • That is actually us?

  • Atoms, can't see them. Nobody ever will. They're smaller than the wavelength of light.

  • Gas, can't see that. Interesting, somebody mentioned 1600 recently.

  • Gas was invented in 1600 by a Dutch chemist called Van Helmont.

  • It's said to be the most successful ever invention of a word by a known individual.

  • Quite good. He also invented a word called blas, meaning astral radiation.

  • Didn't catch on, unfortunately. (Laughter)

  • But well done, Him. Light -- you can't see light.

  • When it's dark, in a vacuum, if a person shines a beam of light straight across your eyes, you won't see it.

  • Slightly technical, some physicists will disagree with this. But it's odd that you can't see the beam of light,

  • you can only see what it hits.

  • Electricity, can't see that. Don't let anyone tell you they understand electricity, they don't.

  • Nobody knows what it is. (Laughter) You probably think the electrons in an electric wire move instantaneously

  • down a wire, don't you, at the speed of light, when you turn the light on.

  • They don't. Electrons bumble down the wire, about the speed of spreading honey, they say.

  • Galaxies -- hundred billion of them, estimated in the universe. Hundred billion.

  • How many can we see? Five. Five, out of a hundred billion galaxies, with the naked eye.

  • And one of them's quite difficult to see, unless you've got very good eyesight.

  • Radio waves. There's another thing. Heinrich Hertz, when he discovered radio waves,

  • in 1887, he called them radio waves because they radiated.

  • Somebody said to him, well what's the point of these, Heinrich? What's the point of these radio waves

  • that you've found? And he said, well I've no idea, but I guess somebody'll find a use for them someday.

  • The biggest thing that's invisible to us is what we don't know.

  • It is incredible how little we know.

  • Thomas Edison once said we don't know one percent of one millionth about anything.

  • And I've come to the conclusion --

  • because you ask this other question: what's another thing we can't see?

  • The point, most of us. What's the point?

  • The point -- what I've got it down to is there are only two questions really worth asking.

  • Why we're here, and what should we do about it while we are?

  • To help you, I've got two things to leave you with, from two great philosophers,

  • perhaps two of the greatest philosopher thinkers of the 20th century.

  • One a mathematician and engineer, and the other a poet.

  • The first is Ludwig Wittgenstein, who said,

  • I don't know why we are here, but I am pretty sure it's not in order to enjoy ourselves.

  • He was a cheerful bastard, wasn't he? (Laughter)

  • And secondly, and lastly, W.H. Auden, one of my favorite poets

  • who said, We are here on earth to help others. What the others are here for, I've no idea.

  • [Get your souvenir photo here! Continue your journey into the unknown!]

(Music)

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