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~ MESSIAEN: Quartet For The End Of Time
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WOMAN: I would say that he is... elderly.
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I think that...
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obviously he's not English.
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He has a rounder face
than most of the English people.
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I should say he's probably continental...
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...if not Eastern continental.
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The lines on his face...
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would be... lines of...
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possible agony.
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I thought at first they were scars.
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It's not a happy face.
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BRONOWSKl: One aim of the physical sciences
has been to give an exact picture
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of the material world.
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One achievement of physics in the 20th century
has been to prove that that aim is unattainable.
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Take a good concrete object,
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the human face.
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This is the face of Stefan Bor-grajewicz,
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who, like me, was born in Poland.
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Here it is, seen by the Polish artist
Feliks Topolski.
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We are aware that these pictures
do not so much fix the face as explore it.
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That the artist is tracing the detail
almost as if by touch.
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And that each line that is added...
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...strengthens the picture...
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...but never makes it final.
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We accept that as the method of the artist.
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But what physics has now done is to show that
that is the only method to knowledge.
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There is no absolute knowledge.
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And those who claim it,
whether they are scientists or dogmatists,
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open the door to tragedy.
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All information is imperfect.
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We have to treat it with humility.
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That's the human condition
and that's what quantum physics says.
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I mean that literally.
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Look at the face across the whole spectrum
of electromagnetic information.
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The question I'm going to ask is
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how fine and how exact
is the detail that we can see
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with the best instruments in the world?
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Even with a perfect instrument,
if we can conceive one.
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And seeing the detail need not be confined
to seeing with visible light.
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The spectrum of visible light from red to violet
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is only an octave or so
in the range of invisible radiations.
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There is a whole keyboard of information,
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all the way from the longest wavelengths
of radio waves - the low notes -
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to the shortest wavelengths
of X-rays and beyond - the highest notes.
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We will shine it all, turn by turn,
on the human face.
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The longest of the invisible waves
are the radio waves,
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whose existence Heinrich Hertz proved
nearly 100 years ago.
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Because they are the longest,
they are also the crudest.
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A radar scanner,
working at a wavelength of a few metres,
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will not see the face at all,
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unless we make the face also
some metres across.
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(Beeps)
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Only when we shorten the wavelength
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does any detail appear on the giant head.
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At a fraction of a metre, the ears.
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And at the limit of radio waves,
a few centimetres,
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the first trace of the man beside the statue.
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(Beeping)
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We are now looking at the face -
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the man 's face, with a camera which is sensitive
to the next range of radiations:
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Less than a millimetre, infra-red.
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The astronomer, William Herschel,
discovered that in 1800,
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by noticing the warmth when he focused
his telescope beyond red light.
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The infra-red rays are heat rays.
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The camera plate translates them into light,
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making the hottest look blue
and the coolest look red or dark.
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We see the rough features of the face.
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The eyes...
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...the mouth...
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...the nose...
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See the heat stream from the nostrils.
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We learn something new about the human face,
yes, but what we learn has no detail.
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At its shortest wavelength,
some hundredths of a millimetre,
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infra-red shades gently into visible red.
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The film is sensitive to both.
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And the face springs to life.
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It's no longer a man - it's the man we know.
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White light reveals him to the eye,
visibly, in detail.
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The small hairs...
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...the pores in the skin...
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a blemish here...
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...a broken blood vessel there.
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White light is a mixture of wavelengths.
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From red... to orange...
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to yellow... to green...
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to blue and to violet -
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the shortest visible waves.
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We ought to see more exact details
with the short violet waves
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than the long red waves.
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But, in practice, a difference of an octave or so
doesn 't help much.
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The painter analyses the face,
takes the features apart...
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...separates the colours...
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enlarges the image.
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It's natural to ask,
"Shouldn 't the scientist use a microscope?"
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Yes, he should.
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But we ought to understand
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that the microscope enlarges the image
but cannot improve it.
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The sharpness or detail is fixed
by the wavelength of the light.
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Here's an enlargement of over 200 times.
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And it can single out an individual cell
in the skin.
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But to get more detail,
we still need a shorter wavelength.
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The next step, then, is ultraviolet light,
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which has a wavelength 1/10,000th
of a millimetre and less,
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shorter by a factor of ten and more
than visible light.
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If our eyes were able to see into the ultraviolet,
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they would see this ghostly landscape
of fluorescence.
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The fact is that, at any wavelength,
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we can intercept a ray only by objects
about as large as a wavelength itself.
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A smaller object simply will not cast a shadow.
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The ultraviolet microscope looks into the cell,
enlarged 3,500 times,
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to the level of single chromosomes.
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But that's the limit.
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No light will see the human genes
within a chromosome.
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Next to the X-rays, they can 't be focused.
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We cannot build an X-ray microscope.
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So we must be content to fire them at the face
and get a sort of shadow.
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The detail depends now on their penetration.
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We see the skull beneath the skin...
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...for example, that the man has lost his teeth.
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This probing of the body made X-rays exciting
as soon as Rontgen discovered them.
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He was the hero who won the first Nobel prize
in 1901.
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A lucky chance in nature
will sometimes let us do more.
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We can map the atoms in a crystal
because their spacing is regular.
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This is the pattern of atoms in the DNA spiral.
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This is what a gene is like.
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The method was invented in 1912
by von Laue
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and was the first proof that atoms are real.
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We have one step more:
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To the electron microscope...
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...where the rays are so concentrated
that we no longer know
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whether to call them waves or particles.
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Electrons are fired at an object,
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and they trace its outline
like a knife-thrower at a fair.
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This is the smallest object that's ever been seen.
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A single atom of thorium.
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It's spectacular,
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and yet even the hardest electrons
do not give a hard outline.
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The perfect image is still
as remote as the distant stars.
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We are here, face to face,
with the crucial paradox of knowledge.
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Year by year,
we devise more precise instruments
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with which to observe nature,
with more fineness.
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And when we look at the observations,
they are as uncertain as ever.
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We seem to be running after a goal
which lurches away from us to infinity,
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every time we come within sight of it.
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Let me put it in the context
of an astronomical observatory.
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This is the observatory that was built for
Karl Friedrich Gauss in Gottingen.
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Throughout his lifetime, and ever since,
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astronomical instruments have been improved.
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We look at the position of a star
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and it seems to us that we are closer and closer
to finding it precisely.
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But when we compare
our individual observations,
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we are astonished and chagrined to find them
as scattered within themselves as ever.
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We had hoped that the human errors
would disappear
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and that we would ourselves have God's view.
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But it turns out that the errors can 't be taken out
of the observations.
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And that's true of stars or atoms
or just looking at somebody's picture,
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or hearing the report of somebody's speech.
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Gauss recognised that with that...
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marvellous, boyish genius that he had,
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right up to the age of nearly 80
at which he died.
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When he was only 18 years old,
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when he came here to Gottingen
to enter the university,
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he had already solved the problem
of the best estimate...
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...of a series of observations
which have internal errors.
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When an observer looks at a star,
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he knows that there's
a multitude of causes for error.
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So he takes several readings.
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And he hopes, naturally, that the best estimate
of the star's position is the average -
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the centre of the scatter.
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So far, so obvious.
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But Gauss pushed on to ask
what the scatter of the errors tells us.
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He devised the Gaussian curve,
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in which the scatter is summarised by
the deviation or spread of the curve.
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And from this came a far-reaching idea.
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The scatter marks an area of uncertainty.
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We are not sure that the true position
is the centre.
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All we can say is that it lies in
an area of uncertainty.
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Gauss was particularly bitter about philosophers
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who claimed that they had a road to knowledge
more perfect than that of observation.
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Of many examples, I will choose one.
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It happens that there is a philosopher
called Friedrich Hegel,
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whom, I must confess, I specifically detest.
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And I am happy to share that profound feeling
with a far greater man, Gauss.
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In 1800, Hegel published a thesis, if you please,
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proving that, although the definition of planets
had changed since the ancients,
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there still could only be, philosophically,
seven planets.
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Well, not only Gauss knew how to answer that -
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Shakespeare had answered that long before.
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There is a marvellous passage in King Lear
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in which who else but the Fool says to the King...
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"The reason why the seven stars
are no more than seven is a pretty reason."
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And the King wags sagely and says,
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"Because they are not eight."
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And the Fool says,
"Yes, indeed. Thou wouldst make a good fool."
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And so did Hegel.
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On 1 st January, 1801,
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punctually, before the ink was dry
on Hegel's dissertation,
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the eighth planet, Ceres, was discovered.
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History has many ironies.
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The time bomb in Gauss's curve is that,
after his death,
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we discover that there is no God's-eye view.
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The errors are inextricably bound up
with the nature of human knowledge.
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And the irony is that the discovery comes here
in Gottingen.
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~ O alte Burschenherrlichkeit
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~ Wohin bist du entschwunden?
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~ Nie kehrst du wieder, goldner Zeit
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~ So froh und ungebunden
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~ Vergebens spahe ich umher
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~ Ich finde deine Spur nicht mehr
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~ O jerum, jerum, jerum...
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Ancient university towns are wonderfully alike.
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(Bell chimes)
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Gottingen is like Cambridge in England
or Yale in America: Very provincial,
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not on the way to anywhere.
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00:19:04,080 --> 00:19:08,835
No-one comes to these backwaters
except for the company of professors.
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And the professors are sure
that this is the centre of the world.
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There's an inscription in the Ratskeller here:
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"Extra Gottingen non est vita."
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"Outside Gottingen there is no life."
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The symbol of the university
is the barefoot goose girl
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that every student kisses at graduation.
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~ Gaudeamus igitur
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~ Juvenes dum sumus
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~ Gaudeamus igitur
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~ Juvenes dum sumus...
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The university is a Mecca,
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to which students come
with something less than perfect faith.
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It's important that students bring a certain
ragamuffin irreverence to their studies.
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They're not here to worship what is known,
but to question it.
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Like every university,
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the Gottingen landscape is criss-crossed
with long walks that professors take after lunch.
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The research students are ecstatic
if they're asked along.
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Perhaps Gottingen in the past
had been rather sleepy.
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The small German university towns go back
to a time before the country was united,
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and this gives them
a flavour of local bureaucracy.
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Even after 1918,
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they were more conformist
than universities outside Germany.
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(Train whistle)
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The link between Gottingen
and the outside world was the railway.
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That was the way the visitors came
from Berlin and abroad,
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eager to exchange the new ideas
that were racing ahead in physics.
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It was a byword in Gottingen
that science came to life in the train to Berlin,
244
00:21:43,200 --> 00:21:48,593
because that's where people argued
and contradicted and had new ideas,
245
00:21:48,680 --> 00:21:51,399
and had them challenged too.
246
00:22:02,960 --> 00:22:04,916
In the years of the First World War...
247
00:22:06,800 --> 00:22:12,636
...science was dominated -
at Gottingen as elsewhere - by relativity.
248
00:22:13,680 --> 00:22:20,472
But in 1921,
there was appointed here Max Born...
249
00:22:21,520 --> 00:22:29,279
...who began a series of seminars that brought
everyone interested in atomic physics here.
250
00:22:31,040 --> 00:22:35,352
It was rather strange. Max Born
was almost 40 when he was appointed.
251
00:22:37,160 --> 00:22:40,914
By and large, physicists have done
their best work before they're 30,
252
00:22:41,000 --> 00:22:42,956
mathematicians much earlier,
253
00:22:43,040 --> 00:22:44,996
biologists perhaps a little later.
254
00:22:45,840 --> 00:22:52,678
But Born had a remarkable, personal,
Socratic gift.
255
00:22:52,760 --> 00:22:55,354
He drew young men to him.
256
00:22:56,840 --> 00:23:01,072
He got the best out of them...
257
00:23:02,320 --> 00:23:07,758
...and the ideas that he and they exchanged
and challenged
258
00:23:07,840 --> 00:23:11,116
also produced his best work.
259
00:23:12,880 --> 00:23:16,873
Out of that wealth of names,
whom am I to choose?
260
00:23:18,680 --> 00:23:20,636
Obviously, Werner Heisenberg,
261
00:23:20,720 --> 00:23:25,271
who did his finest work here with Born.
262
00:23:27,480 --> 00:23:34,875
Then, when Erwin Schrodinger published
a different form of basic atomic physics...
263
00:23:35,920 --> 00:23:38,388
...here is where the arguments took place.
264
00:23:38,480 --> 00:23:40,948
And from all over the world, people came here.
265
00:23:41,040 --> 00:23:44,476
It's rather strange to talk in these terms
266
00:23:44,560 --> 00:23:50,078
about a subject which, after all,
is done by midnight oil.
267
00:23:51,480 --> 00:23:59,990
Did physics in the 1920s really consist of
argument, seminar, discussion, dispute?
268
00:24:01,080 --> 00:24:04,072
Yes, it did. Yes, it still does.
269
00:24:04,760 --> 00:24:06,716
The people who met here,
270
00:24:06,800 --> 00:24:09,951
the people who meet in laboratories still...
271
00:24:11,120 --> 00:24:14,749
...only end their work
with the mathematical formulation.
272
00:24:14,840 --> 00:24:19,550
They begin it by trying to solve the riddles
of the subatomic particles,
273
00:24:19,640 --> 00:24:21,596
of the electrons and the rest.
274
00:24:21,680 --> 00:24:25,514
Think of the puzzles
that the electron was setting just at that time.
275
00:24:26,400 --> 00:24:29,073
On Mondays, Wednesdays and Fridays,
276
00:24:29,160 --> 00:24:31,310
it would behave like a particle.
277
00:24:31,400 --> 00:24:36,428
On Tuesdays, Thursdays and Saturdays,
it would behave like a wave.
278
00:24:36,520 --> 00:24:43,392
How could you match those two aspects
brought from the large-scale world
279
00:24:43,480 --> 00:24:45,436
and pushed into a single entity
280
00:24:45,520 --> 00:24:51,550
into this Lilliput Gulliver's Travels world
of the inside of the atom?
281
00:24:51,640 --> 00:24:53,517
That's what it was about.
282
00:24:53,600 --> 00:24:59,675
And that requires, not calculation,
but insight, imagination,
283
00:25:00,480 --> 00:25:02,436
if you like - metaphysics.
284
00:25:02,520 --> 00:25:07,719
I remember a phrase that Max Born used,
when he came to England many years after,
285
00:25:08,400 --> 00:25:11,119
and that still stands, in his autobiography.
286
00:25:11,200 --> 00:25:19,471
He said: "I am now convinced that
theoretical physics is actual philosophy."
287
00:25:23,000 --> 00:25:28,996
Max Born meant that the new ideas in physics
amount to a different view of reality.
288
00:25:31,320 --> 00:25:36,110
The world is not a fixed, solid array of objects
out there.
289
00:25:48,800 --> 00:25:50,756
It shifts under our gaze,
290
00:25:50,840 --> 00:25:52,796
it interacts with us.
291
00:25:52,880 --> 00:25:56,919
The knowledge that it yields
has to be interpreted by us.
292
00:26:02,520 --> 00:26:08,629
There is no way of exchanging information
that does not demand an act of judgment.
293
00:26:09,760 --> 00:26:11,716
Is the electron a particle?
294
00:26:11,800 --> 00:26:14,712
It behaves like one in the Bohr atom.
295
00:26:17,320 --> 00:26:23,509
But de Broglie, in 1924,
produced a beautiful wave model,
296
00:26:23,600 --> 00:26:29,630
in which the orbits are the places
where an exact, whole number of waves
297
00:26:29,720 --> 00:26:31,676
closes round the nucleus.
298
00:26:32,480 --> 00:26:34,436
(Steam train)
299
00:26:47,760 --> 00:26:53,153
Max Born thought of a train of electrons
as if each were riding on a crankshaft.
300
00:26:53,240 --> 00:26:58,598
So that collectively, they constitute
a series of Gaussian curves,
301
00:26:58,680 --> 00:27:00,636
a wave of probability.
302
00:27:08,800 --> 00:27:13,271
A new conception was being made
on the train to Berlin
303
00:27:13,360 --> 00:27:16,318
and the professorial walk in the woods
of Gottingen.
304
00:27:16,400 --> 00:27:21,349
That, whatever fundamental units
the world is put together from,
305
00:27:21,440 --> 00:27:27,151
they are more delicate, more fugitive,
more startling
306
00:27:27,240 --> 00:27:31,313
than we catch in the butterfly net
of our senses.
307
00:27:35,760 --> 00:27:43,952
All those woodland walks and conversations
came to a brilliant climax in 1927.
308
00:27:45,360 --> 00:27:52,436
Early that year, Werner Heisenberg
gave a new characterisation of the electron.
309
00:27:53,600 --> 00:27:56,751
"Yes, it is a particle," he said.
310
00:27:56,840 --> 00:28:02,631
"But a particle which yields
only limited information."
311
00:28:03,720 --> 00:28:10,432
That is, you can specify
where it is at this instant,
312
00:28:11,280 --> 00:28:18,595
but then you cannot impose on it a specific
speed and direction at the setting off.
313
00:28:19,680 --> 00:28:22,752
Or conversely, if you insist
that you're going to fire it
314
00:28:22,840 --> 00:28:25,957
at a certain speed and in a certain direction,
315
00:28:26,040 --> 00:28:31,717
then you cannot specify exactly
what its starting point is,
316
00:28:31,800 --> 00:28:33,995
or, of course, its end point.
317
00:28:35,800 --> 00:28:42,319
That sounds like a very crude characterisation.
318
00:28:42,400 --> 00:28:44,356
It is not.
319
00:28:44,440 --> 00:28:48,718
Heisenberg gave it depth
by making it precise.
320
00:28:51,840 --> 00:28:59,030
The information that the electron carries
is limited in its totality.
321
00:28:59,920 --> 00:29:01,876
That is, for instance...
322
00:29:03,080 --> 00:29:08,757
...its speed and its position
fit together in such a way...
323
00:29:09,800 --> 00:29:15,989
...that they are confined by
the tolerance of the quantum.
324
00:29:19,480 --> 00:29:21,436
That's a profound idea.
325
00:29:23,280 --> 00:29:27,239
One of the great scientific ideas,
not only of the 20th century...
326
00:29:28,280 --> 00:29:33,035
...but of the history of science.
327
00:29:35,440 --> 00:29:38,512
Heisenberg called this
the principle of uncertainty.
328
00:29:40,920 --> 00:29:44,276
In one sense
it's a robust principle of the everyday.
329
00:29:44,360 --> 00:29:47,591
We know that we cannot ask the world
to be exact.
330
00:29:47,680 --> 00:29:55,075
If an object, a face, had to be exactly the same
before we recognised it,
331
00:29:55,160 --> 00:29:59,233
we should never recognise it
from one day to the next.
332
00:30:01,520 --> 00:30:10,235
In the act of recognition, a judgment is built in -
an area of tolerance or uncertainty.
333
00:30:14,440 --> 00:30:20,276
So, Heisenberg's principle says that no events,
not even atomic events,
334
00:30:20,360 --> 00:30:23,636
can be described with certainty -
335
00:30:23,720 --> 00:30:25,711
with zero tolerance.
336
00:30:25,800 --> 00:30:28,314
What makes the principle profound
337
00:30:28,400 --> 00:30:32,791
is that Heisenberg specifies the tolerance
that can be reached.
338
00:30:32,880 --> 00:30:37,431
The measuring rod is Max Planck's quantum:
339
00:30:37,880 --> 00:30:39,836
In the world of the atom,
340
00:30:39,920 --> 00:30:44,710
the area of uncertainty
is always mapped out by the quantum.
341
00:30:49,480 --> 00:30:53,598
Yet the principle of uncertainty is a bad name.
342
00:30:54,680 --> 00:31:00,550
In science or outside of it, we are not uncertain.
343
00:31:02,440 --> 00:31:09,232
Our knowledge is merely confined
within a certain tolerance.
344
00:31:10,760 --> 00:31:14,435
We should call it the principle of tolerance.
345
00:31:15,800 --> 00:31:17,756
First in the engineering sense.
346
00:31:18,720 --> 00:31:21,473
Science has progressed step by step.
347
00:31:21,560 --> 00:31:25,109
The most successful enterprise
in the ascent of man,
348
00:31:25,200 --> 00:31:30,320
because it has understood
that the exchange of information
349
00:31:30,400 --> 00:31:33,392
between man and nature and man and man
350
00:31:33,480 --> 00:31:37,837
can only take place with a certain tolerance.
351
00:31:39,240 --> 00:31:41,196
But I also use the word...
352
00:31:44,400 --> 00:31:48,552
...passionately... about the real world.
353
00:31:51,440 --> 00:31:56,514
All knowledge,
all information between human beings...
354
00:31:58,000 --> 00:32:04,269
...can only be exchanged
within a play of tolerance.
355
00:32:05,360 --> 00:32:09,717
And that's whether it's in science,
or in literature...
356
00:32:10,920 --> 00:32:13,832
...or in religion, or in politics,
357
00:32:13,920 --> 00:32:18,038
or in any form of thought that aspires to dogma.
358
00:32:21,760 --> 00:32:27,676
It's a major tragedy of my lifetime and yours...
359
00:32:29,040 --> 00:32:32,032
...that, here in Gottingen...
360
00:32:33,080 --> 00:32:38,438
...scientists were refining
to the most exquisite precision...
361
00:32:39,960 --> 00:32:41,916
...the principle of tolerance...
362
00:32:44,400 --> 00:32:48,188
...and turning their backs on the fact that,
all around them,
363
00:32:48,280 --> 00:32:55,197
tolerance was crashing to the ground,
beyond repair.
364
00:32:56,480 --> 00:32:58,436
(Train whistle)
365
00:33:05,400 --> 00:33:07,356
~ Alter Jagermarsch
366
00:33:32,560 --> 00:33:35,358
The sky was darkening all over Europe,
367
00:33:35,440 --> 00:33:40,434
but there was one particular cloud which had
been hanging over Gottingen for 100 years.
368
00:33:40,520 --> 00:33:42,556
Early in the 1800s,
369
00:33:42,640 --> 00:33:47,873
Johann Friedrich Blumenbach
had put together a collection of skulls
370
00:33:47,960 --> 00:33:52,715
that he got from distinguished gentlemen
with whom he corresponded all over Europe.
371
00:33:53,760 --> 00:33:56,433
There was no suggestion in Blumenbach's work
372
00:33:56,520 --> 00:34:00,513
that the skulls were to support
a racist division of humanity.
373
00:34:01,720 --> 00:34:07,238
All the same, from the time of his death,
the collection was added to and added to
374
00:34:07,320 --> 00:34:12,235
and became a core of racist,
pan -Germanic theory
375
00:34:12,320 --> 00:34:18,634
which was officially sanctioned by the
National Socialist Party when it came to power.
376
00:34:18,720 --> 00:34:20,676
~ Alter Jagermarsch
377
00:34:35,920 --> 00:34:39,037
When Hitler arrived in 1933,
378
00:34:39,120 --> 00:34:44,877
the tradition of scholarship in Germany
was destroyed almost overnight.
379
00:34:51,120 --> 00:34:54,874
Now the train to Berlin was the symbol of flight.
380
00:34:54,960 --> 00:34:56,916
(Train whistle)
381
00:35:03,960 --> 00:35:07,111
Europe was no longer hospitable
to the imagination -
382
00:35:07,200 --> 00:35:10,272
and not just the scientific imagination.
383
00:35:11,320 --> 00:35:14,278
A whole conception of culture was in retreat:
384
00:35:14,360 --> 00:35:20,037
The conception that human knowledge
is personal and responsible,
385
00:35:20,120 --> 00:35:23,829
an unending adventure
at the edge of uncertainty.
386
00:35:24,680 --> 00:35:28,195
Silence fell, as after the trial of Galileo.
387
00:35:28,280 --> 00:35:32,831
The great men went out into a threatened world.
388
00:35:34,720 --> 00:35:36,676
Max Born.
389
00:35:37,800 --> 00:35:39,756
Erwin Schrodinger.
390
00:35:39,840 --> 00:35:41,796
Albert Einstein.
391
00:35:41,880 --> 00:35:43,836
Sigmund Freud.
392
00:35:43,920 --> 00:35:45,672
Thomas Mann.
393
00:35:46,560 --> 00:35:48,357
Bertolt Brecht.
394
00:35:49,760 --> 00:35:51,716
Toscanini.
395
00:35:51,800 --> 00:35:53,756
Bruno Walter.
396
00:35:53,840 --> 00:35:55,796
Chagall.
397
00:35:55,880 --> 00:35:57,836
Enrico Fermi.
398
00:35:58,760 --> 00:36:06,235
Leo Szilard, coming finally after many years
to the Salk Institute in California.
399
00:36:19,640 --> 00:36:23,189
The principle of uncertainty fixed once for all
400
00:36:23,280 --> 00:36:28,070
the realisation that all knowledge is limited.
401
00:36:29,160 --> 00:36:34,553
It's an irony of history that,
at the very time when this was being worked out,
402
00:36:34,640 --> 00:36:40,112
there should rise, under Hitler in Germany
and tyrants elsewhere,
403
00:36:40,200 --> 00:36:42,156
a counter-conception -
404
00:36:42,240 --> 00:36:45,357
a principle of monstrous certainty.
405
00:36:47,360 --> 00:36:49,920
When the future looks back on the 1930s,
406
00:36:50,000 --> 00:36:56,109
it will think of them as a crucial confrontation
of culture as I have been expounding it.
407
00:36:56,200 --> 00:37:03,754
The ascent of man,
against the throwback of despotic belief,
408
00:37:03,840 --> 00:37:09,073
to the notion that they have absolute certainty.
409
00:37:11,960 --> 00:37:15,669
I must put all those abstractions
into concrete terms,
410
00:37:15,760 --> 00:37:19,719
and I want to do so... in one personality:
411
00:37:20,600 --> 00:37:23,558
Leo Szilard, who was greatly engaged in them,
412
00:37:23,640 --> 00:37:29,715
and with whom I spent
the last year or so of his life
413
00:37:29,800 --> 00:37:32,872
and many afternoons, talking.
414
00:37:36,120 --> 00:37:40,671
Leo Szilard was a Hungarian
whose university life was spent in Germany.
415
00:37:41,720 --> 00:37:46,157
In 1929, he'd published
an important and pioneer paper
416
00:37:46,240 --> 00:37:49,038
on what would now be called
Information Theory:
417
00:37:49,120 --> 00:37:53,636
The relation between knowledge,
nature and man.
418
00:37:55,560 --> 00:38:02,318
But by then, Szilard was certain that Hitler
would come to power, that war was inevitable.
419
00:38:02,400 --> 00:38:06,552
He kept two bags packed in his room,
and, by 1933,
420
00:38:06,640 --> 00:38:09,552
he'd locked them and taken them to England.
421
00:38:11,160 --> 00:38:14,357
It happened that, in September of 1933,
422
00:38:14,440 --> 00:38:17,750
Lord Rutherford,
at the British Association Meeting,
423
00:38:17,840 --> 00:38:23,119
made some remark about
atomic energy never becoming real.
424
00:38:25,000 --> 00:38:28,231
Leo Szilard was the kind of scientist,
425
00:38:28,320 --> 00:38:31,915
perhaps just the kind of good-humoured,
cranky man,
426
00:38:32,000 --> 00:38:35,197
who disliked any statement
that contained the word "never",
427
00:38:35,280 --> 00:38:38,352
particularly when made
by a distinguished colleague.
428
00:38:38,440 --> 00:38:41,876
So he set to mind to think about the problem.
429
00:38:44,400 --> 00:38:49,474
He tells the story
as all of us who knew him would picture it.
430
00:38:49,560 --> 00:38:53,155
He was living at the Strand Palace Hotel -
he loved living in hotels.
431
00:38:54,200 --> 00:38:56,953
He was walking to work at Bart's Hospital,
432
00:38:57,040 --> 00:39:01,272
and as he came to Southampton Row,
he was stopped by a red light.
433
00:39:01,360 --> 00:39:04,432
That's the only part of the story
I find improbable -
434
00:39:04,520 --> 00:39:06,875
I never knew Szilard to stop for a red light.
435
00:39:06,960 --> 00:39:10,589
However, before the light turned to green...
436
00:39:11,840 --> 00:39:17,551
...he had realised that if you hit an atom
with one neutron
437
00:39:17,640 --> 00:39:20,438
and it happens to break up and release two,
438
00:39:20,520 --> 00:39:24,115
then you would have a chain reaction.
439
00:39:25,160 --> 00:39:31,076
He wrote a specification for a patent
which contains the word "chain reaction",
440
00:39:31,160 --> 00:39:33,116
which was filed in 1934.
441
00:39:35,720 --> 00:39:39,315
And now we come to
a part of Szilard's personality
442
00:39:39,400 --> 00:39:46,033
which was characteristic of scientists
at that time,
443
00:39:46,120 --> 00:39:50,398
but which he expressed most clearly and loudly.
444
00:39:50,480 --> 00:39:53,199
He wanted to keep the patent secret.
445
00:39:53,280 --> 00:39:56,636
He wanted to prevent science
from being misused,
446
00:39:56,720 --> 00:40:00,474
and, in fact, he assigned the patent
to the British Admiralty
447
00:40:00,560 --> 00:40:03,199
so that it was not published until after the war.
448
00:40:04,240 --> 00:40:07,516
But meanwhile, war was becoming
more and more inevitable.
449
00:40:08,360 --> 00:40:13,150
The march of progress in nuclear physics
and the march of Hitler
450
00:40:13,240 --> 00:40:18,519
went step by step, pace by pace,
in a way that we forget now.
451
00:40:20,120 --> 00:40:23,795
Early in 1939, Szilard wrote to Joliot-Curie,
452
00:40:23,880 --> 00:40:28,431
asking him if one could make
a prohibition on publication.
453
00:40:28,520 --> 00:40:30,954
He tried to get Fermi not to publish.
454
00:40:31,040 --> 00:40:34,077
But finally, in August of 1939,
455
00:40:34,160 --> 00:40:39,154
he wrote a letter, which Einstein signed
and sent to President Roosevelt,
456
00:40:39,240 --> 00:40:43,472
saying, "Nuclear energy is here.
War is inevitable.
457
00:40:43,560 --> 00:40:47,838
It is for the President to decide
what scientists should do about it."
458
00:40:50,520 --> 00:40:52,476
But he didn 't stop.
459
00:40:52,560 --> 00:40:55,279
When, in 1945, the war had been won,
460
00:40:55,360 --> 00:41:00,070
and he realised that the bomb
was now about to be made
461
00:41:00,160 --> 00:41:01,832
and to be used on the Japanese,
462
00:41:01,920 --> 00:41:04,639
he marshalled protest everywhere he could.
463
00:41:04,720 --> 00:41:07,188
He wrote memorandum after memorandum.
464
00:41:07,280 --> 00:41:11,671
One memorandum to President Roosevelt
only failed because Roosevelt died
465
00:41:11,760 --> 00:41:14,638
during the very days
that he was transmitting it to him.
466
00:41:14,720 --> 00:41:21,831
Always he wanted the bomb to be tested before
the Japanese and an international audience,
467
00:41:21,920 --> 00:41:27,199
so the Japanese should know
and should surrender before people died.
468
00:41:29,160 --> 00:41:31,549
As you know, Szilard failed,
469
00:41:31,640 --> 00:41:35,633
and with him, the community of scientists failed.
470
00:41:37,520 --> 00:41:42,355
The first atomic bomb
was dropped on Hiroshima in Japan,
471
00:41:42,440 --> 00:41:48,834
on 6th August, 1945, at 8:15 in the morning.
472
00:41:58,520 --> 00:42:00,476
(Ticks)
473
00:43:12,280 --> 00:43:14,236
(Aeroplane engine roars)
474
00:43:23,280 --> 00:43:27,114
I had not been long back from Hiroshima
475
00:43:27,200 --> 00:43:31,273
when I heard someone say,
in Szilard's presence...
476
00:43:32,320 --> 00:43:34,675
...that it was the tragedy of scientists...
477
00:43:35,880 --> 00:43:39,555
...that their discoveries were used for destruction.
478
00:43:40,720 --> 00:43:45,555
Szilard replied, as he more than anyone else
had the right to reply,
479
00:43:45,640 --> 00:43:48,438
that it was not the tragedy of scientists -
480
00:43:48,520 --> 00:43:50,829
it is the tragedy of mankind.
481
00:43:54,560 --> 00:43:56,516
(Barrier creaks)
482
00:44:30,120 --> 00:44:31,951
(Door closes)
483
00:44:32,040 --> 00:44:33,996
(Footsteps)
484
00:44:36,160 --> 00:44:39,470
There are two parts to the human dilemma.
485
00:44:41,800 --> 00:44:45,952
One is the belief that the end justifies the means.
486
00:44:49,720 --> 00:44:56,068
That push-button philosophy,
that deliberate deafness to suffering
487
00:44:56,160 --> 00:44:59,277
has become the monster in the war machine.
488
00:45:00,520 --> 00:45:03,353
The other is the betrayal of the human spirit.
489
00:45:04,800 --> 00:45:08,873
The assertion of dogma that closes the mind
490
00:45:08,960 --> 00:45:14,592
and turns a nation, a civilisation,
into a regiment of ghosts.
491
00:45:16,240 --> 00:45:20,119
Obedient ghosts or tortured ghosts.
492
00:45:44,960 --> 00:45:48,714
It's said that science will de-humanise people
493
00:45:48,800 --> 00:45:50,756
and turn them into numbers.
494
00:45:50,840 --> 00:45:54,276
That's false. Tragically false.
495
00:45:55,320 --> 00:46:01,111
Look for yourself. This is the concentration camp
and crematorium at Auschwitz.
496
00:46:01,200 --> 00:46:03,760
This is where people were turned into numbers.
497
00:46:05,720 --> 00:46:12,239
Into this pond were flushed the ashes
of some four million people.
498
00:46:12,320 --> 00:46:14,356
And that was not done by gas.
499
00:46:14,440 --> 00:46:18,638
It was done by arrogance,
it was done by dogma,
500
00:46:18,720 --> 00:46:20,676
it was done by ignorance.
501
00:46:22,600 --> 00:46:26,832
When people believe
that they have absolute knowledge,
502
00:46:26,920 --> 00:46:30,276
with no test in reality, this is how they behave.
503
00:46:31,520 --> 00:46:36,116
This is what men do
when they aspire to the knowledge of gods.
504
00:46:38,200 --> 00:46:41,237
Science is a very human form of knowledge.
505
00:46:41,320 --> 00:46:44,630
We are always at the brink of the known.
506
00:46:45,400 --> 00:46:50,554
We always feel forward for what is to be hoped.
507
00:46:51,560 --> 00:46:57,556
Every judgment in science
stands on the edge of error and is personal.
508
00:47:00,240 --> 00:47:07,749
Science is a tribute to what we can know
althogh we are fallible.
509
00:47:09,120 --> 00:47:12,032
In the end, the words were said
by Oliver Cromwell:
510
00:47:12,120 --> 00:47:16,398
"I beseech you, in the bowels of Christ,
511
00:47:16,480 --> 00:47:19,313
think it possible you may be mistaken."
512
00:47:22,400 --> 00:47:26,109
I owe it as a scientist to my friend, Leo Szilard...
513
00:47:27,160 --> 00:47:31,915
...I owe it as a human being to the many
members of my family who died here,
514
00:47:32,000 --> 00:47:36,232
to stand here as a survivor and a witness.
515
00:47:38,400 --> 00:47:44,396
We have to cure ourselves of the itch
for absolute knowledge and power.
516
00:47:45,520 --> 00:47:49,354
We have to close the distance between the...
517
00:47:51,160 --> 00:47:54,994
...push-button order and the human act.
518
00:47:57,240 --> 00:48:00,357
We have to... touch people.