TEDGlobal 2009
David Deutsch: A new way to explain explanation
David Deutsch: Novi način objašnjavanja objašnjenja
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Desecima tisuća godina naši preci razumijevali su svijet posredstvom mitova, a tempo promjena bio je zamrznut. Uspon znanstvenog razumijevanja promijenio je svijet unutar nekoliko stoljeća. Zašto? Fizičar David Deutch predlaže suptilan odgovor.
David Deutsch - Quantum physicist
David Deutsch's 1997 book "The Fabric of Reality" laid the groundwork for an all-encompassing Theory of Everything, and galvanized interest in the idea of a quantum computer, which could solve problems of hitherto unimaginable complexity. Full bio
David Deutsch's 1997 book "The Fabric of Reality" laid the groundwork for an all-encompassing Theory of Everything, and galvanized interest in the idea of a quantum computer, which could solve problems of hitherto unimaginable complexity. Full bio
Double-click the English transcript below to play the video.
00:18
I'm sure that, throughout the hundred-thousand-odd years
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Siguran sam da, kroz sto tisuća neobičnih godina
00:23
of our species' existence,
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postojanja naše vrste,
00:26
and even before,
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a čak i prije toga,
00:29
our ancestors looked up at the night sky,
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naši preci su gledali prema noćnom nebu
00:31
and wondered what stars are.
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i pitali se što su to zvijezde.
00:34
Wondering, therefore,
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Pitali su se, stoga,
00:36
how to explain what they saw
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kako objasniti ono što su vidjeli
00:40
in terms of things unseen.
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koristeći pojmove neviđenoga.
00:45
Okay, so, most people
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Naravno, većina ljudi
00:49
only wondered that occasionally, like today,
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se samo pitala o tome povremeno, kao i danas,
00:52
in breaks from whatever
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u stankama između onoga
00:54
normally preoccupied them.
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što ih je uobičajeno zaokupljalo.
00:56
But what normally preoccupied them
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Ali, ono što ih je obično zaokupljalo
01:00
also involved yearning to know.
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također je uključivalo i žudnju za znanjem.
01:03
They wished they knew
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Oni su željeli znati
01:06
how to prevent their food supply
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kako spriječiti da im opskrba hrane
01:08
from sometimes failing,
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povremeno zakaže,
01:10
and how they could rest when they were tired
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kako bi se mogli odmarati kad su bili umorni,
01:13
without risking starvation,
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bez preuzimanja rizika gladovanja,
01:17
be warmer, cooler, safer,
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kako biti toplijim, hladnijim, sigurnijim,
01:21
in less pain.
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s manje bola.
01:23
I bet those prehistoric cave artists
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Kladim se da su oni prapovijesni špiljski umjetnici
01:26
would have loved to know
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željeli zbilja znati
01:28
how to draw better.
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kako bolje crtati.
01:30
In every aspect of their lives,
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U svakom aspektu njihovih života,
01:35
they wished for progress, just as we do.
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željeli su napredovati, kao što i mi želimo.
01:40
But they failed, almost completely, to make any.
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Međutim, nisu uspjeli, gotovo u potpunosti, ostvariti bilo kakav napredak.
01:46
They didn't know how to.
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Nisu znali kako.
01:49
Discoveries like fire
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Otkrića, kao što je vatra,
01:53
happened so rarely, that from an individual's point of view,
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su se događala tako rijetko, da s gledišta pojedinca,
01:57
the world never improved.
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svijet nije nikako napredovao.
02:00
Nothing new was learned.
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Ništa novo nije naučeno.
02:04
The first clue to the origin of starlight
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Prva indicija o porijeklu zvjezdanog svjetla
02:07
happened as recently as 1899: radioactivity.
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dogodila se 1899., zapravo nedavno: radioaktivnost.
02:14
Within 40 years,
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Unutar 40 godina,
02:16
physicists discovered the whole explanation,
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fizičari su otkrili cjelovito objašnjenje,
02:20
expressed, as usual, in elegant symbols.
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prikazano, kao i obično, u obliku elegantnih simbola.
02:25
But never mind the symbols.
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Ali, ostavimo po strani simbole.
02:27
Think how many discoveries
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Razmislite, koliko mnogo otkrića
02:31
they represent.
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oni predstavljaju.
02:33
Nuclei and nuclear reactions, of course.
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Jezgru i nuklearne reakcije, naravno.
02:36
But isotopes, particles of electricity,
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Ali i izotope, čestice elektriciteta,
02:43
antimatter,
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antimateriju,
02:47
neutrinos,
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neutrine,
02:49
the conversion of mass to energy -- that's E=mc^2 --
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pretvaranje mase u energiju -- odnosno E=mc^2 --
02:53
gamma rays,
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gama zrake,
02:55
transmutation.
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transmutaciju.
02:59
That ancient dream that had always eluded the alchemists
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Taj drevni san, koji je oduvijek izluđivao alkemičare,
03:04
was achieved through these same theories
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postignut je posredstvom istih ovih teorija
03:06
that explained starlight
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koje su objasnile i zvjezdani sjaj,
03:08
and other ancient mysteries,
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kao i druge drevne misterije,
03:11
and new, unexpected phenomena.
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a i nove, neočekivane fenomene.
03:14
That all that, discovered in 40 years,
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Sve to, otkriveno u 40 godina,
03:18
had not been in the previous hundred thousand,
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nije bilo [otkriveno] u prethodnih sto tisuća godina,
03:21
was not for lack of thinking
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ne zbog izostanka razmišljanja
03:25
about stars, and all those other urgent problems they had.
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o zvijezdama i svim onim drugim gorućim problemima koje su imali.
03:29
They even arrived at answers,
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Čak su i došli do odgovora,
03:32
such as myths,
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poput mitova,
03:34
that dominated their lives,
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koji su dominirali njihovim životima,
03:36
yet bore almost no resemblance
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mada, bez skoro ikakve sličnosti
03:40
to the truth.
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s istinom.
03:42
The tragedy of that protracted stagnation
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Tragedija toga, produžila je stagnaciju,
03:47
isn't sufficiently recognized, I think.
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a čini mi se da to nije dovoljno prepoznato.
03:49
These were people with brains of
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To su bili ljudi s mozgovima,
03:51
essentially the same design
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suštinski iste strukture,
03:54
that eventually did discover all those things.
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koji su u konačnici i otkrili sve one stvari.
03:59
But that ability to make progress
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Ali sposobnost postizanja napretka
04:03
remained almost unused,
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ostala je skoro neiskorištena,
04:06
until the event that
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sve do događaja koji je
04:09
revolutionized the human condition
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preinačio ljudske potencijale
04:11
and changed the universe.
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i promijenio svijet.
04:13
Or so we should hope.
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Ili se barem nadamo da jest.
04:15
Because that event was the
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A taj događaj bila je
04:17
Scientific Revolution,
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znanstvena revolucija,
04:19
ever since which our knowledge
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sve od kada je naše poznavanje
04:21
of the physical world,
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fizičkog svijeta
04:23
and of how to adapt it to our wishes,
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i načina kako ga prilagoditi našim željama
04:27
has been growing relentlessly.
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neumorno raslo.
04:29
Now, what had changed?
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I sad, što se promijenilo?
04:32
What were people now doing for the first time
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Što su tada ljudi po prvi put radili,
04:34
that made that difference
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što je napravilo tu razliku
04:36
between stagnation
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između stagnacije
04:38
and rapid, open-ended discovery?
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i brzog, neograničenog otkrivanja?
04:42
How to make that difference
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Kako napraviti tu razliku
04:44
is surely the most important universal truth
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je zasigurno najvažnija univerzalna istina
04:48
that it is possible to know.
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koju se može spoznati.
04:50
Worryingly, there is no consensus about what it is.
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Zabrinjavajuće je da nema konsenzusa o tome koja je to istina.
04:55
So, I'll tell you.
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Pa, reći ću vam.
04:57
But I'll have to backtrack a little first.
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Ali, morat ću se vratiti malo unatrag.
05:01
Before the Scientific Revolution,
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Prije znanstvene revolucije,
05:04
they believed that everything important, knowable,
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vjerovali su da je sve važno, spoznatljivo,
05:07
was already known,
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već poznato,
05:09
enshrined in ancient writings, institutions,
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sadržano u drevnim napisima, institucijama,
05:12
and in some genuinely useful rules of thumb --
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kao i u nekim istinski korisnim pravilima --
05:15
which were, however, entrenched as dogmas,
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koja su bila, ipak, ukorijenjena kao dogme,
05:19
along with many falsehoods.
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zajedno s mnogim neistinama.
05:21
So they believed that knowledge came from authorities
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Tako su vjerovali da je znanje dolazilo od autoriteta,
05:25
that actually knew very little.
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koji su u biti vrlo malo znali.
05:28
And therefore progress
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I stoga je napredak
05:31
depended on learning how to reject
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ovisio o učenju kako odbaciti
05:34
the authority of learned men,
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autoritet učenih ljudi,
05:37
priests, traditions and rulers.
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svećenika, tradicija i vladara.
05:41
Which is why the Scientific Revolution
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To je razlog zbog kojeg je znanstvena revolucija
05:44
had to have a wider context.
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morala imati širi kontekts:
05:46
The Enlightenment, a revolution in how
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prosvjetiteljstvo, revolucija u okviru koje su
05:50
people sought knowledge,
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ljudi tražili znanje,
05:53
trying not to rely on authority.
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pokušavajući se ne oslanjati na autoritet.
05:56
"Take no one's word for it."
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"Nikome nemojte vjerovati na riječ."
05:58
But that can't be what made the difference.
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Ali to ne može biti ono što je napravilo razliku.
06:02
Authorities had been rejected before, many times.
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Autoriteti su bili odbacivani i prije, mnogo puta.
06:04
And that rarely, if ever,
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I to je rijetko, ako i ikad,
06:06
caused anything like the Scientific Revolution.
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prouzročilo nešto poput znanstvene revolucije.
06:10
At the time, what they thought
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U to vrijeme, ono što su mislili
06:12
distinguished science
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da razlikuje znanost
06:14
was a radical idea about things unseen,
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bila je radikalna ideja o neviđenim stvarima,
06:18
known as empiricism.
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poznata kao empirizam.
06:21
All knowledge derives from the senses.
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Svo znanje prozlazi iz osjetila.
06:26
Well, we've seen that that can't be true.
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Pa, vidjeli smo da to ne može biti istina.
06:29
It did help by promoting
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Pomoglo je u promicanju
06:33
observation and experiment.
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opažanja i eksperimenta.
06:35
But, from the outset, it was obvious
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Ali, od početka je bilo očigledno
06:37
that there was something horribly wrong with it.
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da je bilo nešto užasno pogrešno u tome.
06:40
Knowledge comes from the senses.
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Znanje dolazi od osjetila.
06:42
In what language? Certainly not the language of mathematics,
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U kojem jeziku? Zasigurno ne u jeziku matematike,
06:45
in which, Galileo rightly said,
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u kojem je, kako je Galileo ispravno rekao,
06:48
the book of nature is written.
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napisana knjiga prirode.
06:51
Look at the world. You don't see equations
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Pogledajte svijet. Ne vidite jednadžbe
06:54
carved on to the mountainsides.
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isklesane na obroncima planina.
06:57
If you did, it would be because people
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Kad biste ih vidjeli, to bi bilo stoga jer su ih ljudi
06:59
had carved them.
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isklesali.
07:01
By the way, why don't we do that?
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Usput rečeno, zašto to ne radimo?
07:04
What's wrong with us?
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Što nije u redu s nama?
07:06
(Laughter)
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(Smijeh)
07:07
Empiricism is inadequate
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Empirizam je nedovoljan,
07:09
because, well,
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jer, pa,
07:11
scientific theories explain the seen in terms of the unseen.
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znanstvene teorije objašnjavaju viđeno u terminima neviđenoga.
07:16
And the unseen, you have to admit,
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A neviđeno, morate priznati,
07:18
doesn't come to us through the senses.
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ne dolazi do nas putem osjetila.
07:20
We don't see those nuclear reactions in stars.
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Mi ne vidimo one nuklearne reakcije u zvijezdama.
07:24
We don't see the origin of species.
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Ne vidimo porijeklo vrsta.
07:27
We don't see the curvature of space-time,
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Ne vidimo zakrivljenost prostor-vremena,
07:31
and other universes.
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niti druge svemire.
07:33
But we know about those things.
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Ali znamo o tim stvarima.
07:36
How?
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Kako?
07:38
Well, the classic empiricist answer is induction.
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Pa, klasični odgovor empirista je indukcija.
07:43
The unseen resembles the seen.
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Neviđeno je slično viđenom.
07:47
But it doesn't.
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Ali, zapravo, nije.
07:49
You know what the clinching evidence was
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Znate što je bio ključni dokaz
07:51
that space-time is curved?
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da je prostor-vrijeme zakrivljeno.
07:54
It was a photograph, not of space-time,
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To je bila fotografija, ne prostor-vremena,
07:57
but of an eclipse, with a dot there rather than there.
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već pomrčina, s točkom tamo, umjesto onamo.
08:01
And the evidence for evolution?
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A dokaz evolucije?
08:03
Some rocks and some finches.
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Nekoliko stijena i nekoliko zeba.
08:06
And parallel universes? Again: dots there,
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A paralelni svemiri? Ponovo: točke tamo,
08:09
rather than there, on a screen.
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umjesto onamo, na ekranu.
08:11
What we see, in all these cases,
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Ono što vidimo, u svim ovim slučajevima,
08:14
bears no resemblance to the reality
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nema nikakve sličnosti s realnošću
08:18
that we conclude is responsible --
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za koju zaključujemo da je odgovorna --
08:20
only a long chain of theoretical reasoning
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samo dugi niz teoretskog rezoniranja
08:24
and interpretation connects them.
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i interpretiranja, ono je što ih spaja.
08:26
"Ah!" say creationists.
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"Ah", kažu kreacionisti,
08:29
"So you admit it's all interpretation.
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"Dakle, priznajete da je sve interpretacija.
08:31
No one has ever seen evolution.
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Nitko nikada nije vidio evoluciju.
08:34
We see rocks.
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Vidimo stijene.
08:36
You have your interpretation. We have ours.
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Vi imate svoje interpretacije. Mi imamo svoje.
08:39
Yours comes from guesswork,
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Vaše proizlaze iz nagađanja;
08:41
ours from the Bible."
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naše, iz Biblije."
08:43
But what creationist and empiricists both ignore
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Ali, ono što i kreacionisti i empiristi ignoriraju
08:49
is that, in that sense,
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jest da, u tom smislu,
08:51
no one has ever seen a bible either,
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nitko, također, ni Bibliju nije vidio,
08:54
that the eye only detects light, which we don't perceive.
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da oko samo detektira svjetlo, kojeg ne shvaćamo.
08:58
Brains only detect nerve impulses.
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Mozgovi samo detektiraju impulse živaca.
09:01
And they don't perceive even those as what they really are,
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I ne shvaćaju čak ni one kakvi u biti jesu,
09:04
namely electrical crackles.
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odnosno električne praskove.
09:06
So we perceive nothing as what it really is.
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Dakle, ništa ne shvaćamo onako kakvo u stvarnosti jest.
09:11
Our connection to reality
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Naša veza s realnošću
09:14
is never just perception.
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nikada nije samo percepcija.
09:16
It's always, as Karl Popper put it,
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Uvijek je, kako kaže Karl Popper,
09:20
theory-laden.
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natovarena teorijom.
09:23
Scientific knowledge isn't derived from anything.
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Znanstveno znanje ne proizlazi iz bilo čega.
09:26
It's like all knowledge. It's conjectural, guesswork,
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Kao i svo znanje. Ono je pretpostavljeno, nagađajuće,
09:31
tested by observation,
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provjeravano opažanjem,
09:33
not derived from it.
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a ne izvedeno iz njega.
09:37
So, were testable conjectures
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Dakle, jesu li provjerljive pretpostavke bile
09:40
the great innovation that opened the intellectual prison gates?
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velika inovacija koja je otvorila vrata intelektualnog zatvora?
09:44
No. Contrary to what's usually said,
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Ne. Suprotno od onoga što se obično govori,
09:47
testability is common,
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provjerljivost je uobičajena
09:49
in myths and all sorts of other irrational modes of thinking.
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u mitovima i svim vrstama drugih iracionalnih načina razmišljanja.
09:53
Any crank claiming the sun will go out next Tuesday
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Svaki osobenjak koji tvrdi da će se sunce ugasiti slijedećeg utorka
09:57
has got a testable prediction.
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ima provjerljivo predviđanje.
10:00
Consider the ancient Greek myth
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Uzmite u obzir drevni grčki mit
10:03
explaining seasons.
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koji objašnjava godišnja doba.
10:06
Hades, God of the Underworld,
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Had, Bog podzemlja,
10:08
kidnaps Persephone, the Goddess of Spring,
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oteo je Perseponu, Boginju proljeća,
10:11
and negotiates a forced marriage contract,
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i pregovara o ugovoranju prisilnog braka,
10:14
requiring her to return regularly, and lets her go.
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tražeći od nje da se redovito vraća, a zatim je pušta.
10:18
And each year,
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I svake godine,
10:20
she is magically compelled to return.
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ona je magično primorana vraćati se.
10:23
And her mother, Demeter,
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A njena majka, Demetra,
10:25
Goddess of the Earth,
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Boginja Zemlje,
10:27
is sad, and makes it cold and barren.
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je tužna, te stvara hladnoću i pustoš.
10:32
That myth is testable.
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Taj mit je provjerljiv.
10:35
If winter is caused by Demeter's sadness,
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Ukoliko je zima prouzročena Demetrinom tugom,
10:39
then it must happen everywhere on Earth simultaneously.
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onda se to mora događati svugdje na Zemlji, u isto vrijeme.
10:43
So if the ancient Greeks had only known that Australia
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Tako, da su drevni Grci samo znali da je Australija
10:46
is at its warmest when Demeter is at her saddest,
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najtoplija kad je Demetra najtužnija,
10:50
they'd have known that their theory is false.
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tada bi znali da je njihova teorija pogrešna.
10:53
So what was wrong with that myth,
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Dakle, što je bilo pogrešno s tim mitom,
10:56
and with all pre-scientific thinking,
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kao i sa svim predznanstvenim razmišljanjem,
10:59
and what, then, made that momentous difference?
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i što je, onda, napravilo trenutnu razliku?
11:04
I think there is one thing you have to care about.
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Mislim da ima jedna stvar do koje bi vam trebalo biti stalo.
11:08
And that implies
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A iz nje proizlazi
11:10
testability, the scientific method,
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provjerljivost, znanstvena metoda,
11:13
the Enlightenment, and everything.
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prosvjetiteljstvo i sve ostalo.
11:15
And here is the crucial thing.
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I sad dolazimo do ključne stvari.
11:17
There is such a thing as a defect in a story.
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Postoji nešto kao manjkavost priče.
11:20
I don't just mean a logical defect. I mean a bad explanation.
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Ne mislim samo na logičku manjkavost. Mislim na loše objašnjenje.
11:25
What does that mean? Well, explanation
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Što to znači? Pa, objašnjenje
11:28
is an assertion about what's there, unseen,
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je tvrdnja o onome što je tamo, o neviđenom,
11:31
that accounts for what's seen.
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koja uzima u obzir ono što je viđeno.
11:34
Because the explanatory role
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Jer, uloga objašnjavanja
11:37
of Persephone's marriage contract
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bračnog ugovora Persepone
11:39
could be played equally well
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mogla bi se odigravati podjednako dobro
11:41
by infinitely many other
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putem beskonačno mnogo drugih
11:43
ad hoc entities.
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ad hoc cjelina.
11:45
Why a marriage contract and not any other reason
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Zašto bračni ugovor, a ne neki drugi razlog
11:48
for regular annual action?
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za redovito godišnje djelovanje?
11:52
Here is one. Persephone wasn't released.
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Evo jednog. Persepona nije otpuštena.
11:55
She escaped, and returns every spring
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Pobjegla je i vraća se svakog proljeća
11:59
to take revenge on Hades,
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kako bi se osvetila Hadu,
12:01
with her Spring powers.
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sa svojim proljetnim moćima.
12:03
She cools his domain with Spring air,
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Ona hladi njegov utjecaj proljetnim zrakom,
12:08
venting heat up to the surface, creating summer.
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propuhivajući toplinu gore do površine, stvarajući ljeto.
12:12
That accounts for the same phenomena as the original myth.
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To će dovesti do istog fenomena kao i izvorni mit.
12:16
It's equally testable.
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I jednako je provjerljivo.
12:19
Yet what it asserts about reality
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Ipak, ono što tvrdi o realnosti
12:22
is, in many ways, the opposite.
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jest, na mnoge načine, suprotno.
12:24
And that is possible because
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A to je moguće zbog toga što
12:26
the details of the original myth
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detalji izvornog mita
12:29
are unrelated to seasons,
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nisu u svezi s godišnjim dobima,
12:31
except via the myth itself.
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osim posredstvom samog mita.
12:35
This easy variability
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Ova laka varijabilnost
12:38
is the sign of a bad explanation,
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je znak lošeg objašnjenja.
12:42
because, without a functional reason to prefer
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Jer, bez funkcionalnog razloga za preferenciju
12:46
one of countless variants,
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jedne od bezbrojnih varijanti,
12:51
advocating one of them, in preference to the others,
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braniti jednu od njih, pretpostavljati je drugima,
12:53
is irrational.
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je iracionalno.
12:55
So, for the essence of what
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Tako, radi biti onoga
12:57
makes the difference to enable progress,
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što čini razliku koja omogućuje napredak,
13:00
seek good explanations,
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tražite dobra objašnjenja,
13:02
the ones that can't be easily varied,
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ona koja nije jednostavno mijenjati,
13:05
while still explaining the phenomena.
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dok u isto vrijeme objašnjavaju fenomen.
13:10
Now, our current explanation of seasons
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I sad, naše trenutno objašnjenje godišnjih doba
13:13
is that the Earth's axis is tilted like that,
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jest da se Zemljine osi naginju tako
13:17
so each hemisphere tilts toward the sun for half the year,
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da se svaka hemisfera naginje prema suncu polovicu godine,
13:20
and away for the other half.
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a od sunca drugu polovicu.
13:23
Better put that up.
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Najbolje da to razglasite.
13:25
(Laughter)
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(Smijeh)
13:26
That's a good explanation: hard to vary,
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To je dobro objašnjenje: teško ga je mijenjati,
13:31
because every detail plays a functional role.
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jer svaki detalj igra funkcionalnu ulogu.
13:34
For instance, we know, independently of seasons,
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Primjerice, znamo, neovisno o godišnjim dobima,
13:37
that surfaces tilted away
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da se površine koje su udaljeno nagnute
13:39
from radiant heat are heated less,
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od toplinskog zračenja manje zagrijavaju,
13:42
and that a spinning sphere, in space,
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a da okrećuća kugla, u prostoru,
13:45
points in a constant direction.
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pokazuje stalno u istom pravcu.
13:48
And the tilt also explains
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A naginjanje također objašnjava
13:51
the sun's angle of elevation at different times of year,
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kut nagiba sunca u različitim djelovima godine,
13:55
and predicts that the seasons
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te predviđa da će godišnja doba
13:57
will be out of phase in the two hemispheres.
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biti izvan faze u dvjema hemisferama.
14:00
If they'd been observed in phase,
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Da su bile opažene u fazi,
14:02
the theory would have been refuted.
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teorija bi bila odbačena.
14:04
But now, the fact that it's also a good explanation,
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Ali ovako, činjenica da je to također dobro objašnjenje,
14:09
hard to vary, makes the crucial difference.
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teško promjenjivo, čini ključnu razliku.
14:14
If the ancient Greeks had found out
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Da su drevni Grci otkrili podatak
14:16
about seasons in Australia,
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o godišnjim dobima u Australiji,
14:19
they could have easily varied their myth
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mogli su lako promijeniti svoj mit
14:21
to predict that.
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kako bi to predvidjeli.
14:23
For instance, when Demeter is upset,
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Primjerice, kad je Demetra uznemirena,
14:25
she banishes heat from her vicinity,
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ona protjera vrućinu iz svoje blizine
14:28
into the other hemisphere, where it makes summer.
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u drugu hemisferu, gdje to stvara ljeto.
14:31
So, being proved wrong by observation,
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I tako, kad bi im se opažanjem dokazalo da su u krivu,
14:34
and changing their theory accordingly,
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te kada bi sukladno tome promijenili teoriju,
14:36
still wouldn't have got the ancient Greeks
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to drevne Grge još uvijek ne bi
14:39
one jot closer to understanding seasons,
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ni milimetar približilo razumijevanju godišnjih doba,
14:42
because their explanation was bad: easy to vary.
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jer je njihovo objašnjenje bilo loše: jednostavno za mijenjanje.
14:45
And it's only when an explanation is good
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I samo je onda kad je objašnjenje dobro
14:48
that it even matters whether it's testable.
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uopće i bitno što je provjerljivo.
14:50
If the axis-tilt theory had been refuted,
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Da je teorija o naginjanju osi odbačena,
14:53
its defenders would have had nowhere to go.
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njeni branitelji ne bi znali kamo dalje krenuti.
14:55
No easily implemented change
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Nijedna jednostavno primijenjena promjena
14:58
could make that tilt
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ne bi mogla učiniti da naginjanje
15:00
cause the same seasons in both hemispheres.
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prouzroči ista godišnja doba u obje hemisfere.
15:05
The search for hard-to-vary explanations
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Potraga za teško promjenjivim objašnjenjima
15:08
is the origin of all progress.
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je ishodište svekolikog napretka.
15:11
It's the basic regulating principle
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To je osnovni regulatorni princip
15:14
of the Enlightenment.
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prosvjetiteljstva.
15:16
So, in science, two false approaches blight progress.
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I tako, u znanosti, dva pogrešna pristupa štete napretku.
15:20
One is well known: untestable theories.
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Jedan je dobro poznat: neprovjerljive teorije.
15:23
But the more important one is explanationless theories.
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Ali još važniji pristup su neobjašnjive teorije.
15:27
Whenever you're told that some existing statistical trend will continue,
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Kad god vam kažu da će se neki postojeći statistički trend nastaviti,
15:31
but you aren't given a hard-to-vary account
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ali vam nije dat i teško promjenjiv razlog
15:34
of what causes that trend,
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promjene toga trenda,
15:37
you're being told a wizard did it.
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govori vam se, zapravo, da je to djelo čarobnjaka.
15:39
When you are told that carrots have human rights
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Kad vam kažu da mrkve imaju ljudska prava,
15:42
because they share half our genes --
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jer dijele polovicu naših gena --
15:44
but not how gene percentages confer rights -- wizard.
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ali sada, kako postoci gena daju prava -- čarobnjak.
15:50
When someone announces that the nature-nurture debate
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Kad netko objavi da je rasprava "priroda-odgoj"
15:54
has been settled because there is evidence
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riješena, jer postoje dokazi
15:56
that a given percentage of our
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da je određeni postotak naših
15:58
political opinions are genetically inherited,
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političkih mišljenja genetski naslijeđen,
16:02
but they don't explain how genes cause opinions,
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ali ne objašnjavaju kako geni prouzrokuju mišljenja,
16:06
they've settled nothing. They are saying that our
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zapravo nisu riješili ništa. Oni govore da su naša
16:08
opinions are caused by wizards,
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mišljenja prouzrokovana čarobnjacima,
16:10
and presumably so are their own.
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a pretpostavljeno i njihova vlastita.
16:13
That the truth consists of
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Da se istina sastoji od
16:16
hard to vary assertions about reality
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teško promjenjivih tvrdnji o realnosti
16:20
is the most important fact
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je najvažnija činjenica
16:23
about the physical world.
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o fizičkom svijetu.
16:25
It's a fact that is, itself, unseen,
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Činjenica je da je i ona, sama po sebi, neviđena,
16:28
yet impossible to vary. Thank you.
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a ipak, nemoguće ju je mijenjati. Hvala vam.
16:32
(Applause)
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(Pljesak)
ABOUT THE SPEAKER
David Deutsch - Quantum physicistDavid Deutsch's 1997 book "The Fabric of Reality" laid the groundwork for an all-encompassing Theory of Everything, and galvanized interest in the idea of a quantum computer, which could solve problems of hitherto unimaginable complexity.
Why you should listen
David Deutsch will force you to reconsider your place in the world. This legendary Oxford physicist is the leading proponent of the multiverse (or "many worlds") interpretation of quantum theory -- the idea that our universe is constantly spawning countless numbers of parallel worlds.
In his own words: "Everything in our universe -- including you and me, every atom and every galaxy -- has counterparts in these other universes." If that doesn't alter your consciousness, then the other implications he's derived from his study of subatomic physics -- including the possibility of time travel -- just might.
In The Fabric of Reality, Deutsch tied together quantum mechanics, evolution, a rationalist approach to knowledge, and a theory of computation based on the work of Alan Turing. "Our best theories are not only truer than common sense, they make more sense than common sense,"Deutsch wrote, and he continues to explore the most mind-bending aspects of particle physics.
In 2008, he became a member of the Royal Society of London.
David Deutsch | Speaker | TED.com