The Secret Life of Chaos


The Secret Life of Chaos

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Transcript


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This is a film about one very simple question.

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How did we get here?

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These are the elements and compounds from which all humans are made.

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They're incredibly, almost embarrassingly common.

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In fact, almost 99% of the human body is a mixture of air, water,

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coal and chalk, with traces of other slightly more exotic elements

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like iron, zinc, phosphorus and sulphur.

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In fact, I've estimated that the elements

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which make up the average human cost at most a few pounds.

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But somehow, trillions of these very ordinary atoms conspire miraculously

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to organise themselves into thinking, breathing, living human beings.

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How the wonders of creation are assembled from such simple

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building blocks, is surely the most intriguing question we can ask.

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You may think that answering it is beyond the realm of science.

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But that's changing.

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For the first time, I believe science has pushed past religion

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and philosophy in daring to tackle this most fundamental of questions.

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This film is the story of a series of bizarre

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and interconnected discoveries that reveal a hidden face of nature.

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That woven into its simplest and most basic laws,

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is a power to be unpredictable.

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It's about how inanimate matter with no purpose or design,

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can spontaneously create exquisite beauty.

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It's about how the same laws that make the universe chaotic

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and unpredictable, can turn simple dust into human beings.

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It's about the discovery that there is a strange

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and unexpected relationship between order and chaos.

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The natural world really is one great, blooming, buzzing confusion.

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It's a mess of quirky shapes and blotches.

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What patterns there are, are never quite regular,

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and never seem to repeat exactly.

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The idea that all this mayhem, all this chaos, is underpinned,

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indeed determined, by mathematical rules,

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and that we can work out what those rules might be,

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runs counter to our most dearly held intuitions.

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So not surprisingly, the first man to really take on the momentous task

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of unravelling nature's mysterious mathematics,

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had a very special and unusual mind.

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He was both a great scientist and a tragic hero.

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He was born in 1912, in London.

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His name was Alan Turing.

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Alan Turing was a remarkable man,

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one of the greatest mathematicians who ever lived.

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He discovered many of the fundamental ideas

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that underpin the modern computer.

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Also, during the Second World War,

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he worked here at Bletchley Park, just outside today's Milton Keynes,

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in what was then a secret government project called Station X,

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which was set up to crack the German military codes.

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The Station X code breakers proved highly effective,

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and Turing's contribution was crucial.

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The work he personally did to crack German naval codes,

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saved thousands of Allied lives and was a turning point in the war.

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But code breaking was just one aspect of Turing's genius.

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Just one part of his uncanny ability to see patterns

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that are hidden from the rest of us.

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For Turing, the natural world offered up the ultimate codes.

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And over the course of his life

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he'd come tantalisingly close to cracking them.

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Turing was a very original person.

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And he had realised that there was this possibility

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that simple mathematical equations

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might describe aspects of the biological world.

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And no-one had thought of that before.

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Of all nature's mysteries, the one that fascinated Turing most

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was the idea that there might be a mathematical basis

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to human intelligence.

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Turing had very personal reasons for believing in this.

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It was the death of this young man, Christopher Morcom,

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who...Alan Turing, well, he was gay,

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and it had been the great emotional thing of his life at that point.

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Christopher Morcom suddenly died.

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And, Alan Turing was obviously very emotionally disturbed by this.

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But you can see that he wanted to put this

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in an intellectual context, a scientific context.

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And the question he wanted to put into context was

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what happens to the mind? What is it?

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Turing became convinced that mathematics could be used to describe

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biological systems, and ultimately intelligence.

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This fascination would give rise to the modern computer,

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and later in Turing's life, an even more radical idea.

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The idea that a simple mathematical description could be given

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for a mysterious process that takes place in an embryo.

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The process is called morphogenesis, and it's very puzzling.

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At first, all the cells in the embryo are identical.

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Then, as this footage of a fish embryo shows,

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the cells begin to clump together,

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and also become different from each other.

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How does this happen? With no thought,

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no central co-ordination?

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How do cells that start off identical, know to become say, skin,

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while others become part of an eye?

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Morphogenesis is a spectacular example

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of something called self-organisation.

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And before Turing, no-one had a clue how it worked.

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Then, in 1952, Turing published this, his paper

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with the world's first mathematical explanation for morphogenesis.

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The sheer chutzpah of this paper was staggering.

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In it, Turing used a mathematical equation

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of the kind normally seen in papers on astronomy or atomic physics,

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to describe a living process.

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No-one had done anything like this.

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Crucially, Turing's equations did, for the first time,

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describe how a biological system could self-organise.

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They showed that something smooth and featureless can develop features.

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One of the astonishing things about Turing's work

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was that starting with the description

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of really very simple processes

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governed by very simple equations, by putting these together,

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suddenly complexity emerged.

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The pattern suddenly came out as a natural consequence.

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And I think in many ways this was very, very unexpected.

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In essence, Turing's equations described something quite familiar,

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but which no-one had thought of in the context of biology before.

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Think of the way a steady wind blowing across sand

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creates all kinds of shapes.

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The grains self-organise into ripples, waves and dunes.

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This happens, even though the grains are virtually identical,

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and have no knowledge of the shapes they become part of.

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Turing argued that in a very similar way,

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chemicals seeping across an embryo

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might cause its cells to self-organise into different organs.

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These are Turing's own very rough scribblings of how this might work.

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They show how a completely featureless chemical soup,

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can evolve these strange blobs and patches.

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In his paper, he refined his sketches

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to show how his equations could spontaneously create markings

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similar to those on the skins of animals.

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Turing went around showing people pictures saying,

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"Doesn't this look a bit like the patterns on a cow?"

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And everyone sort of went, "What is this man on about?"

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But actually, he knew what he was doing.

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They did look like the patterns of a cow, and that's one of

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the reasons why cows have this dappled pattern or whatever.

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So, an area where mathematics had never been used before,

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pattern formation in biology, animal markings,

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suddenly the door was opened and we could see

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that mathematics might be useful in that sort of area.

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So even though Turing's exact equations are not the full story,

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they are the first piece of mathematical work that showed

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there was any possibility of doing this kind of thing.

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Of course, we now know that morphogenesis

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is much more complicated than the process Turing's equations describe.

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In fact, the precise mechanism of how DNA molecules in our cells interact

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with other chemicals, is still fiercely debated by scientists.

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But Turing's idea that whatever is going on is, deep down,

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a simple mathematical process, was truly revolutionary.

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I think Alan Turing's paper is probably the cornerstone

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in the whole idea of how morphogenesis works.

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What it does is it provides us with a mechanism,

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something that Darwin didn't, for how pattern emerges.

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Darwin, of course, tells us that once you have a pattern

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and it is coded for in the genes, that may or may not be passed on,

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depending on circumstances. But what it doesn't do

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is explain where that pattern comes from in the first place.

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That's the real mystery.

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And so, what Turing had done was to suddenly provide

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an accessible chemical mechanism for doing this. That was amazing.

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Turing was onto a really big, bold idea.

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But sadly, we can only speculate how his extraordinary mind

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would have developed his idea.

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Shortly after his groundbreaking paper on morphogenesis,

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a dreadful and completely avoidable tragedy destroyed his life.

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After his work breaking codes at Bletchley Park,

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you might well have assumed that Turing would have been honoured

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by the country he did so much to protect.

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This couldn't be further from the truth.

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What happened to him after the war was a great tragedy,

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and one of the most shameful episodes in the history of British science.

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The same year Turing published his morphogenesis paper,

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he had a brief affair with a man called Arnold Murray.

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The affair went sour

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and Murray was involved in a burglary at Turing's house.

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But when Turing reported this to the police,

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they arrested him as well as Murray.

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In court, the prosecution argued

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that Turing, with his university education, had led Murray astray.

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He was convicted of gross indecency.

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The judge then offered Turing a dreadful choice.

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He could either go to prison, or sign up to a regime of

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female hormone injections to cure him of his homosexuality.

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He chose the latter, and it was to send him into a spiral of depression.

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On 8 June 1954, Turing's body was found by his cleaner.

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He'd died the day before by taking a bite from an apple

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he'd laced with cyanide, ending his own life.

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Alan Turing died aged just 41.

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The loss to science is incalculable.

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Turing would never know that his ideas would inspire

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an entirely new mathematical approach to biology,

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and that scientists would find equations like his

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really do explain many of the shapes that appear on living organisms.

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Looking back, we now know Turing had really grasped the idea

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that the wonders of creation are derived from the simplest of rules.

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He had, perhaps unexpectedly, taken the first step

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to a new kind of science.

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The next step in the story was just as unexpected,

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and in many ways, just as tragic as Turing's.

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In the early 1950s, around the time of Turing's seminal paper

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on morphogenesis, a brilliant Russian chemist by the name of

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Boris Belousov was beginning his own investigations

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into the chemistry of nature.

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Deep behind the iron curtain, in a lab at the Soviet Ministry of Health,

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he was beginning to investigate the way our bodies

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extract energy from sugars.

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Just like Turing, Belousov was working on a personal project, having

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just finished a distinguished career as a scientist in the military.

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In his lab, Belousov had formulated a mixture of chemicals

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to mimic one part of the process of glucose absorption in the body.

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The mix of chemicals sat on the lab bench in front of him,

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clear and colourless while being shaken.

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As he mixed in the final chemical, the whole solution changed colour.

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Now this isn't particularly remarkable.

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If we mix ink into water, it changes colour.

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But then something happened that made no sense at all.

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The mixture began to go clear again.

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Belousov was astounded.

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Chemicals can mix together and react.

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But they shouldn't be able to go back on themselves,

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to apparently unmix without intervention.

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You can change from a clear mixture to a coloured mixture, fine.

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But surely not back again?

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And it got weirder.

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Belousov's chemicals didn't just spontaneously go into reverse.

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They oscillated.

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They switched back and forth from coloured to clear,

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as if they were being driven by some sort of hidden chemical metronome.

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With meticulous care, he repeated his experiments again and again.

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It was the same every time.

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His mixture would cycle from clear to coloured and back again, repeatedly.

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He'd discovered something that was almost like magic,

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a physical process that seemed to violate the laws of nature.

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'Convinced he'd discovered something of great importance, Belousov

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'wrote up his findings, keen to share his discovery with the wider world.

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'But when he submitted his paper to a leading Russian scientific journal,

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'he received a wholly unexpected and damning response.'

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The editor of the journal told Belousov that his findings in the lab

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were quite simply impossible.

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They contravened the fundamental laws of physics.

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The only explanation was that Belousov had made a mistake

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in his experiment, and the work was simply not fit for publication.

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'The rejection crushed Belousov.

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'Deeply insulted by the suggestion his work had been botched,

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'he abandoned his experiments.

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'Soon he gave up science altogether.'

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The tragic irony was that, divided as they were by the Iron Curtain,

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Belousov never encountered Turing's work.

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For if he had, he would have been completely vindicated.

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It turns out that Belousov's oscillating chemicals,

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far from contravening the laws of physics,

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were actually a real world example

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of precisely the behaviour Turing's equations predicted.

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While the connection might not appear obvious at first sight,

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other scientists showed that if you left a variation

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of Belousov's chemicals, unstirred in a Petri dish,

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instead of simply oscillating, they self-organise into shapes.

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In fact, they go beyond Turing's simple blobs and stripes

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to create stunningly beautiful structures and patterns

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out of nowhere.

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The amazing and very unexpected thing about the BZ reaction

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is that someone had discovered a system

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which essentially reproduces the Turing equations.

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And so, from what looks like a very, very bland solution

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emerge these astonishing patterns of waves and scrolls and spirals.

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Now this is emphatically not abstract science.

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The way Belousov's chemicals move as co-ordinated waves

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is exactly the way our heart cells are co-ordinated as they beat.

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Animal skins and heart beats.

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Self-organisation seems to operate all over the natural world.

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So why were the scientific community in Turing and Belousov's day,

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so uninterested, or even hostile to this astonishing and beautiful idea?

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Well, the reason was all too human.

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Mainstream scientists simply didn't like it.

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To them it seemed to run counter to science,

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and all that it had achieved.

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To change that view would require a truly shocking

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and completely unexpected discovery.

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In essence, by the beginning of the 20th century,

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scientists saw the universe as a giant,

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complicated, mechanical device.

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Kind of a super-sized version of this orrery.

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The idea was that the universe is a huge and intricate machine

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that obeys orderly mathematical rules.

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If you knew the rules of how the machine was configured to start with,

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as you turned the handle, over and over again,

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it would behave in an entirely predictable way.

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Back in the times of Isaac Newton

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when people were discovering the laws that drove the universe,

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they came up with this kind of metaphor of a clockwork universe.

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The universe looked like a machine which had been set going at the

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instant of creation and just followed the rules and ticked along.

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And it was a complicated machine and therefore complicated things happen.

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But once you set it going it would only do one thing,

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and the message that people drew from this

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was that anything describable by mathematical rules

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must actually basically be fairly simple.

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Find the mathematics that describes a system

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and you can then predict how that system will unfold.

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That was the big idea.

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It began with Newton's law of gravity

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which can be used to predict how a planet moves around the sun.

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Scientists soon found many other equations just like it.

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Newtonian physics seemed like the ultimate crystal-ball.

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It held up the tantalising possibility

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that the future could, in principle, be known.

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The more careful your measurements are today,

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the better you can predict what will happen tomorrow.

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But Newtonianism had a dangerous consequence.

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If a nice mathematical system, that worked in a similar way

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to my orrery, did sometimes become unpredictable, scientists assumed

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some malign outside force was causing it. Perhaps dirt had got in?

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Perhaps the cogs were wearing out?

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Or perhaps someone had tampered with it?

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Basically we used to think, if you saw very irregular behaviour

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in some problem you're working on, this must be the result of some sort

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of random outside influences, it couldn't be internally generated.

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It wasn't an intrinsic part of the problem,

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it was some other thing impacting on it.

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Looked at from this point of view,

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the whole idea of self-organisation seemed absurd.

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The idea that patterns of the kind Turing and Belousov had found

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could appear of their own accord,

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without any outside influence, was a complete taboo.

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The only way for self-organisation to be accepted

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was for the domineering Newtonian view to collapse.

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But that seemed very unlikely.

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After all, by the late '60s it had delivered

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all the wonders of the modern age.

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Beautiful, beautiful.

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-Ain't that something?

-Magnificent desolation.

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But then, at the same time as the moon mission,

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a small group of scientists, all ardent Newtonians,

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quite unexpectedly found something wasn't right.

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Not right at all.

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During the second half of the 20th century,

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a devil was found in the detail. A devil that would ultimately

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shatter the Newtonian dream and plunge us literally into chaos.

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Ironically, the events that forced scientists to take self-organisation

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seriously was the discovery of a phenomenon known as chaos.

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Chaos is one of the most over-used words in English, but in science

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it has a very specific meaning. It says that a system that is completely

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described by mathematical equations is more than capable

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of being unpredictable without any outside interference whatsoever.

0:26:480:26:53

There's a widespread misapprehension that chaos is just somehow saying,

0:26:550:26:59

the very familiar fact, that everything's complicated.

0:26:590:27:03

I mean, the nitwit chaoticist in Jurassic Park,

0:27:030:27:06

was under that confusion.

0:27:060:27:08

It's something much simpler and yet much more complicated than that.

0:27:080:27:12

It says, some very, very simple rules or equations,

0:27:120:27:17

with nothing random in them, they're completely determined,

0:27:170:27:21

we know everything about the rule,

0:27:210:27:23

can have outcomes that are entirely unpredictable.

0:27:230:27:29

Chaos is one of the most unwelcome discoveries in science.

0:27:310:27:37

The man who forced the scientific community to confront it

0:27:370:27:41

was an American meteorologist called Edward Lorenz.

0:27:410:27:45

In the early 1960s he tried to find mathematical equations

0:27:450:27:49

that could help predict the weather.

0:27:490:27:52

Like all his contemporaries, he believed that in principle

0:27:550:28:00

the weather system was no different to my orrery.

0:28:000:28:03

A mechanical system that could be described

0:28:030:28:06

and predicted mathematically.

0:28:060:28:09

But he was wrong.

0:28:100:28:11

When Lorenz wrote down what looked like perfectly simple mathematical

0:28:150:28:19

equations to describe the movement of air currents,

0:28:190:28:23

they didn't do what they were supposed to.

0:28:230:28:26

They made no useful predictions whatsoever.

0:28:260:28:30

It was as if the lightest breath of wind one day could make the

0:28:330:28:37

difference a month later between a snowstorm and a perfectly sunny day.

0:28:370:28:44

How can a simple system that works in the regular clockwork manner

0:28:460:28:51

of my orrery become unpredictable?

0:28:510:28:54

It's all down to how it's configured.

0:28:540:28:57

How the gears are connected.

0:28:570:28:59

In essence, under certain circumstances,

0:28:590:29:02

the tiniest difference in the starting positions of the cogs,

0:29:020:29:07

differences that are too small to measure,

0:29:070:29:10

can get bigger and bigger with each turn of the handle.

0:29:100:29:15

With each step in the process the system then moves

0:29:150:29:18

further and further away from where you thought it was going.

0:29:180:29:23

Lorenz captured this radical idea in an influential talk he gave called,

0:29:230:29:28

"Does a flap of a butterfly's wings in Brazil set off a tornado in Texas?"

0:29:280:29:35

It was a powerful and evocative image

0:29:400:29:42

and within months a new phrase had entered our language.

0:29:420:29:46

"The butterfly effect."

0:29:460:29:48

And the butterfly effect, the hallmark of all chaotic systems,

0:29:500:29:54

started turning up everywhere.

0:29:540:29:56

In the early '70s, a young Australian called Robert May,

0:30:000:30:04

was investigating a mathematical equation

0:30:040:30:07

that modelled how animal populations changed over time.

0:30:070:30:12

But here too lurked the dreaded butterfly effect.

0:30:120:30:16

Immeasurably small changes to the rates at which the animals reproduced

0:30:160:30:20

could sometimes have huge consequences

0:30:200:30:23

on their overall population.

0:30:230:30:25

Numbers could go up and down wildly for no obvious reason.

0:30:250:30:31

The idea that a mathematical equation gave you the power

0:30:310:30:35

to predict how a system will behave, was dead.

0:30:350:30:41

In some sense this is the end of the Newtonian dream.

0:30:410:30:44

When I was a graduate student, the belief was,

0:30:440:30:48

as we got more and more computer power,

0:30:480:30:52

we'd be able to solve ever more complicated sets of equations.

0:30:520:30:57

But this said that's not necessarily true.

0:30:570:31:00

You could have the simplest equations you can think of,

0:31:000:31:03

with nothing random in them, you know everything.

0:31:030:31:07

And yet, if they have behaviour

0:31:070:31:12

that gives you chaotic solutions,

0:31:120:31:15

then you can never know the starting point accurately enough.

0:31:150:31:20

Centuries of scientific certainty dissolved in just a few short years.

0:31:230:31:29

The truth of the clockwork universe turned out to be just an illusion.

0:31:290:31:34

Something which had seemed a logical certainty,

0:31:340:31:37

revealed itself merely as an act of faith.

0:31:370:31:40

And what's worse, the truth had been staring us in the face all the time.

0:31:400:31:44

Because chaos is everywhere.

0:31:440:31:47

It seemed unpredictability was hard-wired

0:31:510:31:55

into every aspect of the world we live in.

0:31:550:31:58

The global climate could dramatically change

0:32:000:32:04

in the course of a few short years.

0:32:040:32:07

The stock markets could crash without warning.

0:32:070:32:09

We could be wiped from the face of the planet overnight

0:32:090:32:14

and there is nothing anyone could do about it.

0:32:140:32:18

Unfortunately, I have to tell you that all of this is true.

0:32:230:32:28

And yet to be scared of chaos is pointless.

0:32:280:32:31

It's woven into the basic laws of physics.

0:32:330:32:37

And we really all have to accept it as a fact of life.

0:32:370:32:42

The idea of chaos really did have a big impact over a period of about 20

0:32:420:32:47

or 30 years, because it changed the way everyone thought about

0:32:470:32:50

what they were doing in science.

0:32:500:32:52

It changed it to the point

0:32:520:32:53

that they forgot that they'd ever believed otherwise.

0:32:530:32:56

What chaos did was to show us that the possibilities inherent

0:32:560:33:02

in the simple mathematics are much broader and much more general

0:33:020:33:07

than you might imagine. And so a clockwork universe can

0:33:070:33:12

nonetheless behave in the rich, complex way that we experience.

0:33:120:33:17

The discovery of chaos

0:33:190:33:21

was a real turning point in the history of science.

0:33:210:33:24

As it tore down the Newtonian dream,

0:33:240:33:27

scientists began to look more favourably at Turing and

0:33:270:33:30

Belousov's work on spontaneous pattern formation.

0:33:300:33:34

And perhaps more importantly, as they did so,

0:33:340:33:38

they realised something truly astonishing.

0:33:380:33:41

That there was a very deep and unexpected link.

0:33:410:33:44

A truly cosmic connection

0:33:440:33:47

between nature's strange power to self-organise

0:33:470:33:51

and the chaotic consequences of the butterfly effect.

0:33:510:33:55

Between them, Turing, Belousov, May and Lorenz,

0:33:550:34:00

had all discovered different faces of just one really big idea.

0:34:000:34:05

They discovered that the natural world could be deeply,

0:34:080:34:12

profoundly, unpredictable. But the very same things that make it

0:34:120:34:16

unpredictable also allow it to create pattern and structure.

0:34:160:34:21

Order and chaos.

0:34:210:34:24

It seems the two are more deeply linked

0:34:240:34:26

than we could have ever imagined.

0:34:260:34:28

So how is this possible?

0:34:300:34:32

What do phenomena as apparently different as the patterns in

0:34:320:34:36

Belousov's chemicals and the weather, have in common?

0:34:360:34:40

First, though both systems behave in very complicated ways,

0:34:430:34:47

they are both based on surprisingly simple mathematical rules.

0:34:470:34:52

Secondly, these rules have a unique property.

0:34:560:35:00

A property that's often referred to as coupling, or feedback.

0:35:000:35:05

To show you what I mean, to show you both order and chaos can emerge

0:35:100:35:15

on the their own from a simple system with feedback, I'm going to do

0:35:150:35:20

what seems at first glance like a rather trivial experiment.

0:35:200:35:24

This screen behind me is connected up to the camera that's filming me.

0:35:290:35:35

But the camera in turn is filming me with the screen.

0:35:350:35:39

This creates a loop with multiple copies of me

0:35:390:35:43

appearing on the screen.

0:35:430:35:45

This is a classic example of a feedback loop.

0:35:460:35:51

We get a picture, in a picture, in a picture.

0:35:510:35:55

At first it seems fairly predictable.

0:35:550:35:57

But as we zoom the camera in

0:35:570:36:00

some pretty strange things begin to happen.

0:36:000:36:03

The first thing I notice is that the object I'm filming

0:36:050:36:08

stops bearing much resemblance to what now appears on the screen.

0:36:080:36:13

Small changes in the movement of the match become rapidly amplified

0:36:170:36:22

as they loop round from the camera to the screen and back to the camera.

0:36:220:36:27

So even though I can describe each step in the process mathematically,

0:36:300:36:35

I still have no way of predicting how tiny changes

0:36:350:36:39

in the flickering of the flame will end up in the final image.

0:36:390:36:42

This is the butterfly effect in action.

0:36:460:36:49

But now here comes the spooky bit.

0:36:550:36:58

With just a slight tweak to the system,

0:37:000:37:03

these strange and rather beautiful patterns begin to emerge.

0:37:030:37:09

The same system, one that's based on simple rules with feedback,

0:37:110:37:16

produces chaos and order.

0:37:160:37:19

The same mathematics is generating chaotic behaviour

0:37:270:37:31

and patterned behaviour.

0:37:310:37:34

This changes completely how you think about all of this.

0:37:340:37:38

The idea that there are regularities in nature and then,

0:37:380:37:41

totally separately from them,

0:37:410:37:44

are irregularities, and these are just two different things,

0:37:440:37:47

is just not true.

0:37:470:37:49

These are two ends of a spectrum of behaviour

0:37:490:37:51

which can be generated by the same kind of mathematics.

0:37:510:37:55

And it's the closest thing we have at the moment to the kind of true mathematics of nature.

0:37:550:38:00

I think one of the great take home messages from Turing's work and from

0:38:010:38:06

the discoveries in chemistry and biology and so on, is that

0:38:060:38:10

ultimately, pattern formation seems to be woven, very, very deeply

0:38:100:38:13

into the fabric of the universe. And it actually takes some very simple

0:38:130:38:17

and familiar processes, like diffusion,

0:38:170:38:20

like the rates of chemical reactions,

0:38:200:38:22

and the interplay between them naturally gives rise to pattern.

0:38:220:38:26

So pattern is everywhere, it's just waiting to happen.

0:38:260:38:30

From the '70s on, more and more scientists

0:38:320:38:36

began to embrace the concept that chaos

0:38:360:38:39

and pattern are built into nature's most basic rules.

0:38:390:38:44

But one scientist more than any other brought a fundamentally new

0:38:440:38:48

understanding to this astonishing and often puzzling idea.

0:38:480:38:52

He was a colourful character and something of a maverick.

0:38:540:38:58

His name is Benoit Mandelbrot.

0:38:580:39:01

Benoit Mandelbrot wasn't an ordinary child.

0:39:030:39:07

He skipped the first two years of school

0:39:070:39:09

and as a Jew in war-torn Europe his education was very disrupted.

0:39:090:39:14

He was largely self-taught or tutored by relatives.

0:39:140:39:18

He never formally learned the alphabet,

0:39:180:39:21

or even multiplication beyond the five times table.

0:39:210:39:24

But, like Alan Turing,

0:39:270:39:29

Mandelbrot had a gift for seeing nature's hidden patterns.

0:39:290:39:33

He could see rules where the rest of us see anarchy.

0:39:330:39:37

He could see form and structure,

0:39:370:39:39

where the rest of us just see a shapeless mess.

0:39:390:39:42

And above all, he could see that a strange new kind of mathematics

0:39:420:39:47

underpinned the whole of nature.

0:39:470:39:49

Mandelbrot's lifelong quest was to find a simple mathematical basis

0:39:530:39:57

for the rough and irregular shapes of the real world.

0:39:570:40:02

Mandelbrot was working for IBM

0:40:050:40:07

and he was not in the normal academic environment.

0:40:070:40:10

And he was working on a pile of different problems

0:40:100:40:13

about irregularities in nature, in the financial markets,

0:40:130:40:17

all over the place.

0:40:170:40:18

And I think at some point it dawned on him that everything

0:40:180:40:21

he was doing seen to be really parts of the same big picture.

0:40:210:40:25

And he was a sufficiently original and unusual person that

0:40:250:40:30

he realised that pursuing this big picture was what

0:40:300:40:34

-he really wanted to do.

-To Mandelbrot, it seemed perverse that

0:40:340:40:37

mathematicians had spent centuries contemplating idealised shapes

0:40:370:40:42

like straight lines or perfect circles.

0:40:420:40:45

And yet had no proper or systematic way of describing the rough

0:40:450:40:49

and imperfect shapes that dominate the real world.

0:40:490:40:53

Take this pebble.

0:40:550:40:57

Is it a sphere or a cube?

0:40:580:41:01

Or maybe a bit of both?

0:41:010:41:03

And what about something much bigger? Look at the arch behind me.

0:41:030:41:08

From a distance, it looks like a semi-circle.

0:41:080:41:12

But up close, we see that it's bent and crooked.

0:41:120:41:15

So what shape is it?

0:41:170:41:19

Mandelbrot asked if there's something unique

0:41:230:41:25

that defines all the varied shapes in nature.

0:41:250:41:29

Do the fluffy surfaces of clouds, the branches in trees and rivers,

0:41:290:41:33

the crinkled edges of shorelines, share a common mathematical feature?

0:41:330:41:39

Well, they do.

0:41:390:41:42

Underlying nearly all the shapes in the natural world is a mathematical

0:41:420:41:47

principle known as self-similarity. This describes anything in which the

0:41:470:41:53

same shape is repeated over and over again at smaller and smaller scales.

0:41:530:42:00

A great example are the branches of trees.

0:42:020:42:04

They fork and fork again, repeating that simple process

0:42:040:42:08

over and over at smaller and smaller scales.

0:42:080:42:13

The same branching principle applies in the structure of our lungs

0:42:140:42:19

and the way our blood vessels are distributed throughout our bodies.

0:42:190:42:23

It even describes how rivers split into ever smaller streams.

0:42:250:42:30

And nature can repeat all sorts of shapes in this way.

0:42:300:42:33

Look at this Romanesco broccoli.

0:42:350:42:38

Its overall structure is made up of a series of repeating cones

0:42:380:42:42

at smaller and smaller scales.

0:42:420:42:46

Mandelbrot realised self-similarity

0:42:470:42:50

was the basis of an entirely new kind of geometry.

0:42:500:42:54

And he even gave it a name - fractal.

0:42:540:42:58

Now, that's a pretty neat observation.

0:43:000:43:03

But what if you could represent this property of nature in mathematics?

0:43:030:43:07

What if you could capture its essence to draw a picture?

0:43:070:43:11

What would that picture look like?

0:43:110:43:13

Could you use a simple set of mathematical rules

0:43:130:43:17

to draw an image that didn't look man-made?

0:43:170:43:20

The answer would come from Mandelbrot.

0:43:200:43:23

Who had taken a job at IBM in the late 1950s

0:43:230:43:26

to gain access to its incredible computing power

0:43:260:43:30

and pursue his obsession with the mathematics of nature.

0:43:300:43:35

Armed with a new breed of super-computer,

0:43:350:43:38

he began investigating a rather curious

0:43:380:43:42

and strangely simple-looking equation

0:43:420:43:44

that could be used to draw a very unusual shape.

0:43:440:43:48

What I'm about to show you is one of the most remarkable

0:43:480:43:52

mathematical images ever discovered. Epic doesn't really do it justice.

0:43:520:43:59

This is the Mandelbrot set.

0:43:590:44:03

It's been called the thumbprint of God.

0:44:030:44:07

And when we begin to explore it, you'll understand why.

0:44:070:44:10

Just as with the tree or the broccoli,

0:44:180:44:21

the closer you study this picture, the more detail you see.

0:44:210:44:25

Each shape within the set

0:44:290:44:31

contains an infinite number of smaller shapes.

0:44:310:44:34

Baby Mandelbrots that go on for ever.

0:44:340:44:37

Yet all this complexity stems from just one incredibly simple equation.

0:44:430:44:48

This equation has a very important property.

0:44:490:44:53

It feeds back on itself.

0:44:530:44:55

Like a video loop, each output becomes the input for the next go.

0:44:560:45:02

This feedback means that an incredibly simple mathematical

0:45:060:45:09

equation can produce a picture of infinite complexity.

0:45:090:45:14

The really fascinating thing

0:45:310:45:33

is that the Mandelbrot set isn't just a bizarre mathematical quirk.

0:45:330:45:38

Its fractal property of being similar at all scales

0:45:380:45:42

mirrors a fundamental ordering principle in nature.

0:45:420:45:46

Turing's patterns, Belousov's reaction and Mandelbrot's fractals

0:45:510:45:57

are all signposts pointing to a deep underlying natural principle.

0:45:570:46:02

When we look at complexities in nature, we tend to ask,

0:46:050:46:08

"Where did they come from?"

0:46:080:46:10

There is something in our heads that says

0:46:100:46:13

complexity does not arise out of simplicity.

0:46:130:46:15

It must arise from something complicated. We conserve complexity.

0:46:150:46:19

But what the mathematics in this whole area is telling us

0:46:190:46:22

is that very simple rules naturally give rise to very complex objects.

0:46:220:46:27

And so if you look at the object, it looks complex, and you think about

0:46:270:46:30

the rule that generates it, it's simple.

0:46:300:46:32

So the same thing is both complex and simple

0:46:320:46:35

from two different points of view. And that means we have to rethink

0:46:350:46:38

completely the relation between simplicity and complexity.

0:46:380:46:42

Complex systems can be based on simple rules.

0:46:450:46:50

That's the big revelation.

0:46:500:46:52

And it's an astonishing idea.

0:46:520:46:55

It seems to apply all over our world.

0:46:560:46:59

Look at a flock of birds. Each bird obeys very simple rules.

0:47:100:47:15

But the flock as a whole does incredibly complicated things.

0:47:150:47:19

Avoiding obstacles, navigating the planet with no single leader

0:47:190:47:25

or even conscious plan. But amazing though this flock's behaviour is,

0:47:250:47:31

it's impossible to predict how it will behave.

0:47:310:47:34

It never repeats exactly what it does,

0:47:360:47:39

even in seemingly identical circumstances.

0:47:390:47:42

It's just like the Belousov reaction.

0:47:450:47:48

Each time you run it, the patterns produced are slightly different.

0:47:480:47:53

They may look similar, but they are never identical.

0:47:530:47:56

The same is true of video loops and sand dunes.

0:47:560:48:01

We know they'll produce a certain kind of pattern,

0:48:010:48:05

but we can't predict the exact shapes.

0:48:050:48:08

The big question is, can nature's ability to turn simplicity

0:48:120:48:17

into complexity in this mysterious and unpredictable way

0:48:170:48:21

explain why life exists?

0:48:210:48:24

Can it explain how a universe full of simple dust

0:48:260:48:29

can turn into human beings?

0:48:290:48:32

How inanimate matter can spawn intelligence?

0:48:330:48:37

At first, you might think that this is beyond the remit of science.

0:48:390:48:43

If nature's rules are really unpredictable,

0:48:430:48:46

should we simply give up?

0:48:460:48:48

Absolutely not. In fact, quite the opposite.

0:48:480:48:51

Fittingly, the answer to this problem lies in the natural world.

0:48:540:48:58

All around us, there exists a process that engineers

0:48:580:49:03

these unpredictable complex systems

0:49:030:49:05

and hones them to perform almost miraculous tasks.

0:49:050:49:10

The process is called evolution.

0:49:120:49:15

Evolution has built on these patterns.

0:49:170:49:20

It's taken them as the raw ingredients.

0:49:200:49:22

It's combined them together in various ways,

0:49:220:49:26

experimented to see what works and what doesn't,

0:49:260:49:29

kept the things that do work and then built on that.

0:49:290:49:34

It's a completely unconscious process,

0:49:340:49:36

but basically that's what's happening.

0:49:360:49:38

Everywhere you look, you can see evolution

0:49:380:49:41

using nature's self-organising patterns.

0:49:410:49:45

Our hearts use Belousov-type reactions to regulate how they beat.

0:49:450:49:50

Our blood vessels are organised like fractals.

0:49:500:49:54

Even our brain cells interact according to simple rules.

0:49:540:50:00

The way evolution refines and enriches complex systems

0:50:000:50:05

is one of the most intriguing ideas in recent science.

0:50:050:50:09

My interest in my PhD research in complex systems was to see

0:50:120:50:15

how complex systems interact with evolution.

0:50:150:50:18

So, on the one hand you have systems that almost organise themselves

0:50:180:50:22

as complex systems, so they exhibit order that you wouldn't expect,

0:50:220:50:26

but on the other hand, you still have to have evolution interact with

0:50:260:50:30

that to create something that is truly adapted to the environment.

0:50:300:50:33

Evolution's mindless, yet creative, power to develop

0:50:330:50:38

and shape complex systems is indeed incredible.

0:50:380:50:42

But it operates on a cosmic timescale.

0:50:430:50:46

From the first life on Earth, to us walking about,

0:50:480:50:51

took in the region of 3.5 billion years.

0:50:510:50:55

But we now have in our hands

0:50:560:50:59

a device that can mimic this process on a much shorter timescale.

0:50:590:51:04

What is the invention I'm talking about?

0:51:040:51:08

Well, there's a good chance you've been sitting in front of one all day.

0:51:080:51:12

It is, of course, the computer.

0:51:130:51:16

Computers today can churn through trillions of calculations per second.

0:51:210:51:27

And that gives them the power to do something very special.

0:51:270:51:30

They can simulate evolution.

0:51:300:51:34

More precisely, computers can use the principles of evolution to shape

0:51:350:51:40

and refine their own programs, in the same way the natural world

0:51:400:51:44

uses evolution to shape and refine living organisms.

0:51:440:51:49

And today, computer scientists find that this evolved software

0:51:490:51:55

can solve problems that would be beyond the smartest of humans.

0:51:550:52:00

One thing that we found particularly in our original research is how

0:52:000:52:04

powerful evolution is as a system, as an algorithm, to create something

0:52:040:52:08

that is very complex and to create something that is very adaptive.

0:52:080:52:12

Torsten and his team's goal was nothing less

0:52:120:52:16

than to use computerised evolution

0:52:160:52:18

to create a virtual brain that would control a virtual body.

0:52:180:52:23

To begin with, they created 100 random brains.

0:52:240:52:29

As you can see, they weren't up to much.

0:52:290:52:31

Evolution then took over.

0:52:330:52:35

The computer selected the brains that were slightly better

0:52:350:52:40

at moving their bodies and got them to breed.

0:52:400:52:43

The algorithm then takes those individuals that do the best

0:52:450:52:49

and it allows them to create offspring.

0:52:490:52:51

The best movers of the next generation

0:52:530:52:56

were then bred together and so on and on.

0:52:560:52:59

Amazingly, after just 10 generations,

0:52:590:53:03

although they're still a bit unsteady, the figures could walk.

0:53:030:53:08

Eventually, miraculously, you actually end up

0:53:090:53:11

with something that works. The slightly scary thing

0:53:110:53:14

is you don't know why it works and how it works.

0:53:140:53:17

You look at that brain and you have no idea actually what's going on

0:53:170:53:20

because evolution has optimised it automatically.

0:53:200:53:23

In 20 generations, evolution had turned this...

0:53:260:53:31

..into this.

0:53:310:53:33

But these evolved computer beings soon went far beyond just walking.

0:53:360:53:41

They evolved to do things

0:53:440:53:46

that really are impossible to program conventionally.

0:53:460:53:49

They react realistically to unexpected events.

0:53:530:53:57

Like being hit or falling over.

0:53:570:54:00

Even though we programmed these algorithms, what actually happens

0:54:030:54:07

when it unfolds live, we don't control any more

0:54:070:54:10

and things happen that we never expected.

0:54:100:54:12

And it's quite a funny feeling

0:54:120:54:14

that you create these algorithms but then they do their own thing.

0:54:140:54:18

An unthinking process of evolutionary trial and error

0:54:240:54:28

has created these virtual creatures that can move and react in real time.

0:54:280:54:34

What we're seeing here is fantastic experimental evidence

0:54:390:54:43

for the creative power of systems based on simple rules.

0:54:430:54:47

Watching how computers can unconsciously evolve programs

0:54:570:55:02

to do things that no human could consciously program

0:55:020:55:05

is a fantastic example of the power of self-organisation.

0:55:050:55:11

It demonstrates that evolution is itself

0:55:110:55:14

just like the other systems we've encountered.

0:55:140:55:18

One based on simple rules and feedback.

0:55:180:55:21

From which complexity spontaneously emerges.

0:55:210:55:25

Think about it. The simple rule is that the organism

0:55:260:55:30

must replicate with a few random mutations now and again.

0:55:300:55:36

The feedback comes from the environment

0:55:360:55:39

which favours the mutations that are best suited to it.

0:55:390:55:43

The result is ever-increasing complexity,

0:55:430:55:47

produced without thought or design.

0:55:470:55:51

The interesting thing is that one can move up

0:55:520:55:55

to a higher level of organisation. Once you have organisms

0:55:550:55:58

that actually have patterns on them, these can be selected for

0:55:580:56:02

or selected against by processes which are essentially feedbacks.

0:56:020:56:07

And so evolution itself, the whole Darwinian scheme,

0:56:070:56:11

is, in a sense, Turing again

0:56:110:56:14

with feedbacks happening through different processes.

0:56:140:56:17

And that's the essence of this story.

0:56:190:56:21

Unthinking, simple rules have the power to create

0:56:210:56:26

amazingly complex systems without any conscious thought.

0:56:260:56:30

In that sense, these computer beings are self-organised systems,

0:56:310:56:36

just like the one Belousov observed happening in his chemicals.

0:56:360:56:41

Just like the ones in sand dunes and the Mandelbrot sets,

0:56:420:56:46

in our lungs, our hearts, in weather

0:56:460:56:51

and in the geography of our planet.

0:56:510:56:53

Design does not need an active, interfering designer.

0:56:530:56:58

It's an inherent part of the universe.

0:56:580:57:02

One of the things that makes people so uncomfortable about this idea of,

0:57:060:57:10

if you will, spontaneous pattern formation, is that somehow or other

0:57:100:57:15

you don't need a creator. But perhaps a really clever designer,

0:57:150:57:19

what he would do, is to kind of treat the universe

0:57:190:57:22

like a giant simulation, where you set some initial condition

0:57:220:57:26

and just let the whole thing spontaneously happen

0:57:260:57:30

in all of its wonder and all of its beauty.

0:57:300:57:32

The mathematics of pattern formation shows that the same kind of pattern

0:57:350:57:39

can show up in an enormous range of different physical,

0:57:390:57:42

chemical, biological systems. Somewhere deep down inside,

0:57:420:57:46

it's happening for the same mathematical reason.

0:57:460:57:49

Implicit in those facts are these beautiful patterns

0:57:490:57:53

that we see everywhere.

0:57:530:57:55

This, I think, is a mind-blowing thought.

0:57:550:57:58

So, what is the ultimate lesson we can take from all this?

0:58:070:58:12

Well, it's that all the complexity of the universe,

0:58:120:58:15

all its infinite richness,

0:58:150:58:18

emerges from mindless simple rules, repeated over and over again.

0:58:180:58:23

But remember, powerful though this process is,

0:58:230:58:27

it's also inherently unpredictable.

0:58:270:58:30

So although I can confidently tell you that the future will be amazing,

0:58:300:58:36

I can also say, with scientific certainty,

0:58:360:58:40

that I have no idea what it holds.

0:58:400:58:43

Subtitles by Red Bee Media Ltd

0:59:040:59:07

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0:59:070:59:10

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