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We've been told to go out on a limb and say something surprising.
譯者: Shih Hsin-Han 審譯者: Adrienne Lin
So I'll try and do that,
我們將竭盡所能且陳述些驚人之語。
but I want to start with two things that everyone already knows.
因此我會努力的達到這一點。但是
And the first one, in fact, is something that has been known
我想先從大家都知道的兩件事說起。
for most of recorded history,
第一件事,事實上這是
and that is, that the planet Earth, or the solar system,
從有記錄的歷史以來就眾所周知的事。
or our environment or whatever,
就是這地球,或者太陽系,
is uniquely suited to sustain our evolution --
或者說我們的環境,等諸如此類,
or creation, as it used to be thought --
是獨一無二地適合並維持我們的進化,或者說創造,正如我們以前所理解的一樣
and our present existence, and most important, our future survival.
適合我們當下的生存,最重要的是我們未來的生存。
Nowadays, this idea has a dramatic name: Spaceship Earth.
今天這一個概念有個戲劇化的名字-太空船地球。
And the idea there is that outside the spaceship,
在這個概念裡,太空船之外
the universe is implacably hostile,
宇宙不可調和地充滿敵意,
and inside is all we have, all we depend on,
而其內部是我們賴以為生的一切。
and we only get the one chance: if we mess up our spaceship,
我們只有一次機會:如果我們弄壞我們的太空船,
we've got nowhere else to go.
我們將無處可去.
Now, the second thing that everyone already knows
第二件大家都知道的事是
is that, contrary to what was believed for most of human history,
與我們在人類歷史中大部份時間所堅信的相反
human beings are not, in fact, the hub of existence.
人類事實上並不是存在的中心.
As Stephen Hawking famously said,
就如史蒂芬·霍金說過
we're just a chemical scum on the surface of a typical planet
我們只是存在於典型的星球表面的化學汙垢
that's in orbit around a typical star,
這個典型的星球在軌道上環繞著一個典型的恆星,
which is on the outskirts of a typical galaxy, and so on.
且位於一個典型的銀河系的邊緣,以此類推.
Now, the first of those two things that everyone knows is kind of saying
大家都知道的兩件事當中的第一件
that we're at a very un-typical place, uniquely suited and so on,
大概是說我們存在於一個非常不典型的地方.
and the second one is saying that we're at a typical place.
獨一無二的適合性等.
And, especially if you regard these two as deep truths to live by
而第二件事卻說我們存在於一個典型的地方.
and to inform your life decisions,
尤其是當你將這兩件事當作生命中深刻的真理
then they seem a little bit to conflict with each other.
並以此作為你人生決策的依據.
But that doesn't prevent them from both being completely false.
那麼他們似乎彼此有些衝突.
(Laughter)
但這也無法改變他們都是徹底錯誤的這個事實.
And they are.
他們就是錯誤的.讓我從第二件事說起:
So let me start with the second one:
典型-這是一個典型的地方嗎?讓我們看看
"Typical." Well, is this a typical place?
隨便望去.我們會看到一面牆.還有一些化學汙垢
Well, let's look around, you know, look in a random direction,
而這在宇宙中一點也不典型.
and we see a wall, and chemical scum --
你只要朝著同一個方向走數百英里,然後往回看
(Laughter)
你跟本不會看到任何牆或著化學污垢
and that's not typical of the universe at all.
你所能看到的是一個藍色星球.如果你繼續前行.
All you've got to do is go a few hundred miles in that same direction
你會看到太陽,太陽系,以及恆星等等.
and look back,
然而這在宇宙中仍然不算典型.因為恆星存在於星系中.
and you won't see any walls or chemical scum at all --
宇宙中的大部份地方,或著說宇宙中一個典型的地方.
all you see is a blue planet.
不是任何靠近星系的地方.
And if you go further than that,
因次我們繼續前行.直到我們走出星系,然後再往回看.
you'll see the Sun, the solar system and the stars and so on,
是的,你會看到巨大的星系,它螺旋形的觸手展現在我們面前.
but that's still not typical of the universe,
而到達此地,我們已經跨越了十萬光年.
because stars come in galaxies.
但是我們認然一點也沒有靠近宇宙中的典型地方.
And most places in the universe, a typical place in the universe,
要到達典型底方.
is nowhere near any galaxies.
你需要跨越此距離約1000倍,直到你到達星系間的地方.
So let's go out further, till we're outside the galaxy, and look back,
那裡看上去是什麼樣子呢?典型的.
and yeah, there's the huge galaxy with spiral arms laid out in front of us.
那麼宇宙中一個典型的地方看上去是怎樣的呢?
And at this point, we've come 100,000 light-years from here.
在這裡,TED不惜代價,給大家安排了一次高清晰的
But we're still nowhere near a typical place in the universe.
模擬的星系間空間的真實體驗
To get to a typical place,
--星系間空間的景觀.
you've got to go 1,000 times as far as that,
請將電燈關閉,我們就可以看到了.
into intergalactic space.
不太準確,不是非常完美--看到了嗎?星系間的空間
And so, what does that look like -- "typical?"
--星系間的空間是徹底黑暗的,極端地黑暗.
What does a "typical" place in the universe look like?
這個空間是如此的黑暗,假使你正盯著離你最近的恆星,
Well, at enormous expense, TED has arranged
這顆恆星正好發生超新星爆炸,
a high-resolution immersion virtual reality rendering
當光線射到你的時候,假使你正直直地盯著它看
of the view from intergalactic space.
你甚至連微弱的閃光都無法看到.
Can we have the lights off, please, so we can see it?
宇宙就是如此的巨大、黑暗
Well, not quite, not quite perfect.
這還沒有考慮超新星爆炸的光線是如此強烈明亮
You see, intergalactic space is completely dark, pitch dark.
你在距離它數光年的地方會立即斃命.
It's so dark,
但是在星系間的空間,它是如此的遙遠,你甚至無法看見.
that if you were to be looking at the nearest star to you,
那裡也非常寒冷
and that star were to explode as a supernova,
不超過絕對零度三度.
and you were to be staring directly at it at the moment when its light reached you,
什麼都沒有.那裡真空的濃度比
you still wouldn't be able to see even a glimmer.
目前地球上最好的技術可以產生的真空濃度的一百萬分之一還要小.
That's how big and how dark the universe is.
所以這就是宇宙裡一個典型的地方與這兒如何不同.
And that's despite the fact that a supernova is so bright,
也就是說我們現在所處的這個地方是如此地不典型.
so brilliant an event,
請開燈,謝謝.
that it would kill you stone dead at a range of several light-years.
那麼我們如何瞭解距離離我們如此遙遠的一個環境呢?
(Laughter)
與我們所熟悉的一切相比,它是如次不同,如此陌生.
And yet, from intergalactic space,
地球--我們的環境,以我們這一形式存在-- 創造知識.
it's so far away you wouldn't even see it.
這又意味著什麼呢?朝我們剛去過的地方的更遠處望去
It's also very cold out there --
我的意思是從這裡開始,利用望遠鏡--你會看到類似恆星的東西.
less than three degrees above absolute zero.
他們叫做類星體.類星體原意是指類似恆星的物體.
And it's very empty.
也就是說是指看上去有點像恆星的物體. 但他們不是恆星.
The vacuum there is one million times less dense than the highest vacuum
我們已經知道他們是什麼了.數十億年前,數十億光年之外,
that our best technology on Earth can currently create.
一個星系中心的物質朝著
So that's how different a typical place is from this place.
一個巨大的黑洞塌陷.
And that is how un-typical this place is.
隨後密集的磁場對重力塌陷中的一些能量產生了導向作用.
So can we have the lights back on please? Thank you.
其中一些物質.
Now, how do we know about an environment that's so far away and so different
以巨大的噴射流得形式逃離,照亮了宏偉的太空,
and so alien from anything we're used to?
--我認為相當於一千億個太陽的光亮.
Well, the Earth -- our environment, in the form of us --
然而,與這樣一個噴射流的物理相比,我們大腦的物理大鄉逕庭到極點.
is creating knowledge.
在這樣的環境裡,我們連一瞬間都無法生存
Well, what does that mean?
當我們試著描述那樣的噴射流中的狀況,語言變得無法表達.
Well, look out even further than we've just been --
這可能有點像經歷一次超新星爆炸,
I mean from here, with a telescope --
但是是在零距離接觸並且將數百萬年的能量集中到同一時間爆發
and you'll see things that look like stars, they're called quasars.
但是,這個噴射流發生得如此地精確,以至於數十億年後
"Quasars" originally meant "quasi-stellar object,"
在宇宙的另一端,一些化學污垢可以準確地描述
which means "things that look a bit like stars."
建立模型,並預測和解釋,最重要的是 你可以找得到參考
(Laughter)
現實中曾經發生過的事.
But they're not stars.
一個物理系統,大腦,
And we know what they are.
包含了另一個物理系統的準確工作模型 --類星體.
Billions of years ago and billions of light-years away,
不僅是個粗淺的圖像,雖然也包含圖像,
the material at the center of a galaxy collapsed
而且還包含解釋性的模型,這表達同樣的數學
towards a super-massive black hole.
關係和依樣的因果結構.
And then intense magnetic fields
這就是知識.如過這還不夠讓你驚訝的話,
directed some of the energy of that gravitational collapse
一個結構表達另外一個的準確性
and some of the matter
正隨著時間不斷提高.這就是知識的增長.
back out in the form of tremendous jets,
因此,物理規律擁有這樣一個特殊的性質.
which illuminated lobes
物體,不管他們彼此多麼相異,
with the brilliance of -- I think it's a trillion -- suns.
卻仍然能夠表現同樣的數學和因果結構,
Now, the physics of the human brain could hardly be more unlike
而且隨著時間增長表現的越來越多.
the physics of such a jet.
因次我們是與眾不同的化學污垢.這化學污垢擁有普適性.
We couldn't survive for an instant in it.
他的結構準確度越來越高地包容著,
Language breaks down when trying to describe
世界萬物的結構.這個地方,不是宇宙中任何其他地方,
what it would be like in one of those jets.
在它自身內部,成為包容其他一切宇宙萬物結構性和因果性精髓的中心.
It would be a bit like experiencing a supernova explosion,
因此,意義深遠的是,
but at point-blank range and for millions of years at a time.
物理規律允許這現象, 甚至主導了它的發生
(Laughter)
是關於物理世界的最重要的事情之一.
And yet, that jet happened in precisely such a way
那麼太陽系-我們的環境,以我們的形式
that billions of years later, on the other side of the universe,
是如何獲取這樣一個宇宙其他部份的特殊關係的呢?
some bit of chemical scum could accurately describe
史蒂芬霍金觀點中其中一個正確面 -- 這是正確的
and model and predict and explain, above all --
但是著重點是錯的.其中一個正確面是
there's your reference --
它並沒有依賴任何特殊的物理學.沒有特殊的放寬
what was happening there, in reality.
沒有奇蹟發生.他的發生只依賴於我們現在賦有的三種東西
The one physical system, the brain, contains an accurate working model
其中一個是物質,因為知識的增長是一種信息處理的形式.
of the other, the quasar.
信息處理需要計算
Not just a superficial image of it, though it contains that as well,
計算需要點腦
but an explanatory model,
現有的知識都需要物質來製造電腦.
embodying the same mathematical relationships
我們還需要能量來製造電腦,最重要的是
and the same causal structure.
要使得用來紀錄我們所發現知識的媒介工作.
Now, that is knowledge.
第三種東西,較難感觸得到,但是在開放式的知識和解釋的開發中
And if that weren't amazing enough,
同樣關鍵的是證據.
the faithfulness with which the one structure resembles the other
我們的環境中充滿了證據.
is increasing with time.
但是我們經常忽略了測試 比如,牛頓的地球引力定律
That is the growth of knowledge.
大約是在300年前提出的.
So, the laws of physics have this special property,
但是我們習以為常的證據,從數十億年前就在地球上的每個角落裡不斷墜落,
that physical objects as unlike each other as they could possibly be,
也會在接下來的數十億年裡繼續墜落.
can nevertheless embody the same mathematical and causal structure
其他科學也同樣如此.
and to do it more and more so over time.
就我們所知, 發掘所有科學大部分基本真理的證據
So we are a chemical scum that is different.
就在我們的星球上等待我們獲取
This chemical scum has universality.
我們所在的地方充滿了證據,還有物質和能量.
Its structure contains, with ever-increasing precision,
而在星系間的空間中,這三個
the structure of everything.
創造開放式知識的前題條件存在的可能性極端之小.
This place, and not other places in the universe,
正如我所說,那裡空無一物,寒冷,黑暗.抑或不是如此?
is a hub which contains within itself the structural and causal essence
事實上,這只是另外一個狹義的誤解
of the whole of the rest of physical reality.
假想在星系間空間有個立方體存在,
And so, far from being insignificant,
與我們的房屋大小一般,太陽系.以我們的標準來看,這個立方體非常空,
the fact that the laws of physics allow this
但是它事實上仍然包含著超過百萬噸的物質.
or even mandate that this can happen,
一百萬噸足夠建造個,比方說,自給自足的空間站,
is one of the most important things about the physical world.
在這個空間站內聚居著一群科學家,他們致力於不斷創照
Now how does the solar system -- our environment, in the form of us --
開放式的知識,等等.
acquire this special relationship with the rest of the universe?
然而,現在的科技甚至連從星系間空間收集氫氣
Well, one thing that's true about Stephen Hawking's remark --
和將其轉化成別的元素等都遠不能做到.
I mean, it is true, but it's the wrong emphasis.
但問題是,在一個可以理解的宇宙中,
One thing that's true about it is that it doesn't do it with any special physics,
如果某事是物理定律所允許的,
there's no special dispensation, no miracles involved.
那麼在我們知道如何運作的情況下,什麼會妨礙我們去實踐它呢?
It does it simply with three things that we have here in abundance.
換句話說,這是一個關於知識的問題,而不是關於資源.
One of them is matter,
同樣,如果我們可以做到的話,哪麼我們將自動獲得能源供給,
because the growth of knowledge is a form of information processing.
因為這裡得變化將是核反應堆--證據?
Information processing is computation, computation requires a computer --
還是一樣,對人類的感官來說那裡漆黑一片.但是你所需要做的是
there's no known way of making a computer without matter.
拿起望遠鏡,甚至是今天的技術設計,
We also need energy to make the computer, and most important,
往外看去,你會看到我們從這兒看到同樣的星系.
to make the media, in effect, onto which we record
如果你有個更厲害的望遠鏡,你將能看到恆星和行星.
the knowledge that we discover.
在那些星系裡,你可以進行天體物理學研究,瞭解物理定律.
And then thirdly, less tangible but just as essential
在你所處的位置,你可以製造粒子加速器,
for the open-ended creation of knowledge, of explanations,
研究初級粒子物理學,化學等.
is evidence.
也許最難做得科學研究是生物學實地考察,因為需要花費
Now, our environment is inundated with evidence.
數百萬年才能往返最近的有生命得星球.
We happen to get round to testing, let's say, Newton's Law of Gravity,
但是我必須告訴你 --對不起 Richard -
about 300 years ago.
但是我從來都不是那麼喜歡生物學實地考察,
But the evidence that we used to do that
我想我們可以每數百萬年才進行一次.
was falling down on every square meter of the Earth
(觀眾笑聲)
for billions of years before that,
因此事實上,星系間空間並不具備創造開放式知識得前提條件.
and will continue to fall for billions of years afterwards.
任何一個這樣的立方體,在宇宙中任何地方,
And the same is true for all the other sciences.
都可以成為跟我們一樣的中心,
As far as we know, evidence to discover the most fundamental truths
如果履行這一計畫的知識確實存在的話.
of all the sciences is here just for the taking, on our planet.
因此我們並不是唯一熱情好客的地方.
Our location is saturated with evidence
如過星系間空間可以創造出一串開放式得解說,
and also with matter and energy.
那麼幾乎其他所有的環境都是可以的.地球也一樣.被污染的地球也是一樣.
Out in intergalactic space,
而限制性因素,這裡和那裡,不是資源,因為資源很充沛,
those three prerequisites for the open-ended creation of knowledge
而知識,非常匱乏
are at their lowest possible supply --
這樣一個知識型的宇宙觀也許 --我認為應該
as I said, it's empty, it's cold and it's dark out there.
--讓我們感覺非常不平凡.但同時也讓我們感覺到自己的脆弱,
Or is it?
因為這也意味著如果沒有那些必須的具體的知識來幫助我們應對宇宙中
Now actually, that's just another parochial misconception.
源源不斷地挑戰,我們將無法生存.
(Laughter)
僅僅是幾光年外的一個超新星爆炸,我們都將必死無疑.
Because imagine a cube out there in intergalactic space,
Martin Rees 最近剛寫了一本關於我們人類對於所有事物的脆弱性的書,
the same size as our home, the solar system.
從天體物理學,到科學實驗事故,
Now that cube is very empty by human standards,
還有最重要的擁有大規模殺傷性武器的恐怖主義.
but that still means that it contains over a million tons of matter.
他認為人類文明只有50%的機率可以存活過這個世紀.
And a million tons is enough to make, say, a self-contained space station,
我想他晚些時候會在這個會上給大家講述.
on which there's a colony of scientists
但是我認為這一問題並不適合用機率來描述.
that are devoted to creating an open-ended stream of knowledge, and so on.
但是我同意他就此的看法.我們可以生存下去,我們也可能不會續存.
Now, it's way beyond present technology
但是這並不取決於機率,而是我門是否可以及時創造出相關的知識.
to even gather the hydrogen from intergalactic space
這種危險肯定不是前所未有的.物種ㄧ直都在滅絕.
and form it into other elements and so on.
文明也會終至.絕大多數存在過的物種和文明
But the thing is, in a comprehensible universe,
都以成歷史.
if something isn't forbidden by the laws of physics,
如果我們想成為例外的話,邏輯上來看我們唯一的希望
then what could possibly prevent us from doing it, other than knowing how?
是利用將我們這個種群和文明與其他物種區別開的這個特徵,
In other words, it's a matter of knowledge, not resources.
與其他一切都區別開的這個特徵.
If we could do that, we'd automatically have an energy supply,
也就是,我們與物理定律的特殊關係.
because this transmutation would be a fusion reactor.
我們創造新的解釋和知識的能力 成為存在的中心
And evidence?
讓我將此運用到當前的一個論戰中,
Well, again, it's dark out there to human senses,
不是因為我想提議任何特定的解決方法,
but all you've got to do is take a telescope,
而只是用來闡明我所要講述的一些是.
even one of present-day design,
這個論戰就是全球暖化.
look out, and you'll see the same galaxies as we do from here.
我是一個物理學家,但我並不是此領域的物理學家.就全球暖化來說,
And with a more powerful telescope,
我只是個門外漢.對一個門外漢來說理智的做法是
you'll be able to see stars and planets in those galaxies,
嚴肅對待權威的科學理論.而根據這一裡論,
you'll be able to do astrophysics and learn the laws of physics.
已經太晚了,災難在所難免.
And locally there you could build particle accelerators,
因為,如果我們目前最好的選擇是阻止二氧化碳排放的話,
and learn elementary particle physics and chemistry, and so on.
例如通過京都議定書之類的,限制經濟活動,
Probably the hardest science to do would be biology field trips --
以及花費千億美元等巨大的代價,
(Laughter)
那麼不管如何衡量,這就已經是ㄧ個災難了.
because it would take several hundred million years
倡議的行動甚至都不是為解決問題,
to get to the nearest life-bearing planet and back.
而只是稍微推遲災難的到來.因此災難在所難免,ㄧ切都已晚,
But I have to tell you -- and sorry, Richard --
或在所有人意識到這個危險之前就已經太晚了.
but I never did like biology field trips much,
上世紀70年代的時候也許就已經太晚了,
(Laughter)
那時候最先進的科學理論告訴我們工業排放
and I think we can just about make do
將促成一個新的冰河世紀,數十億的人類將從此滅亡.
with one every few hundred million years.
這一教訓對我來說清晰可見,
(Laughter)
我不明白為什麼它沒有傳達至公眾辯論.
So in fact, intergalactic space does contain all the prerequisites
事實是我們不可能永遠知道.當我們知道有一個災難將要降臨,
for the open-ended creation of knowledge.
應對這個災難的成本要比災難本身小,
Any such cube anywhere in the universe
那麼就真的沒有什麼好爭論的.
could become the same kind of hub that we are,
但是沒有任何預防措施,或著預防原則
if the knowledge of how to do so were present there.
可以幫助我們避免我們還沒有預測到的問題.
So, we're not in a uniquely hospitable place.
因次我們需要準備好去解決問題,而不是僅僅避面問題.
If intergalactic space is capable of creating
一盎司的預防等於一盎司的解决,這是事實,
an open-ended stream of explanations,
但是這只是在我們知道預防什麼的情況下.
then so is almost every other environment,
如過你的鼻子被打了一拳,醫學不會教你
so is the Earth.
如何閃躲拳頭.
So is a polluted Earth.
如果醫學不在研究治病的方法,而是僅僅研究預防,
And the limiting factor, there and here,
那麼它將幾乎ㄧ事無成.
is not resources, because they're plentiful,
目前整個世界都在不計成本地忙著計畫來促成
but knowledge, which is scarce.
氣體排放量的減少.
Now this cosmic knowledge-based view may -- and I think ought to --
而它應該趕緊計畫如何降低溫度,
make us feel very special.
以及計畫如何在溫度升高之後如何生存.
But it should also make us feel vulnerable,
不是不計成本,而是有效地,廉價的計畫.而這樣的計畫已經存在了,
because it means that without the specific knowledge
比如在太空中放置大批鏡子來將太陽光反射出去,
that's needed to survive the ongoing challenges of the universe,
以及刺激海洋生物消費更多的二氧化碳.
we won't survive them.
而目前,這些都只是邊緣研究.
All it takes is for a supernova to go off a few light-years away,
人類在應對這個問題或者廣義上來說這些問題的時候,他們起不到核心作用.
and we'll all be dead!
對與我們並未知覺的問題,糾正錯誤的能力--
Martin Rees has recently written a book
不是無限期的躲過,期待發生的絕對好運 --是我們唯一的希望,
about our vulnerability to all sorts of things,
不僅僅是解決問題,而是為生存.
from astrophysics, to scientific experiments gone wrong,
我們應該拿起兩塊石牌,在上面刻上銘文.
and most importantly, to terrorism with weapons of mass destruction.
其中一塊刻上“問題是可以解決的”.
And he thinks that civilization has only a 50 percent chance
另外一塊刻上“問題是不可避免的”
of surviving this century.
謝謝
I think he's going to talk about that later in the conference.
Now, I don't think that probability is the right category
to discuss this issue in,
but I do agree with him about this:
We can survive and we can fail to survive.
But it depends not on chance,
but on whether we create the relevant knowledge in time.
The danger is not at all unprecedented.
Species go extinct all the time.
Civilizations end.
The overwhelming majority of all species and all civilizations
that have ever existed are now history.
And if we want to be the exception to that,
then logically, our only hope is to make use of the one feature
that distinguishes our species and civilization from all the others --
namely, our special relationship with the laws of physics,
our ability to create new explanations, new knowledge --
to be a hub of existence.
So let me now apply this to a current controversy,
not because I want to advocate any particular solution,
but just to illustrate the kind of thing I mean.
And the controversy is global warming.
Now, I'm a physicist, but I'm not the right kind of physicist.
In regard to global warming, I'm just a layman.
And the rational thing for a layman to do
is to take seriously the prevailing scientific theory.
And according to that theory, it's already too late to avoid a disaster,
because if it's true that our best option at the moment is to prevent CO2 emissions
with something like the Kyoto Protocol,
with its constraints on economic activity and its enormous cost
of hundreds of billions of dollars, or whatever it is,
then that is already a disaster by any reasonable measure.
And the actions that are advocated are not even purported to solve the problem,
merely to postpone it by a little.
So it's already too late to avoid it,
and it probably has been too late to avoid it
ever since before anyone realized the danger.
It was probably already too late in the 1970s,
when the best available scientific theory was telling us
that industrial emissions were about to precipitate a new ice age,
in which billions would die.
Now, the lesson of that seems clear to me,
and I don't know why it isn't informing public debate.
It is that we can't always know.
When we know of an impending disaster,
and how to solve it at a cost less than the cost of the disaster itself,
then there's not going to be much argument, really.
But no precautions and no precautionary principle
can avoid problems that we do not yet foresee.
Hence, we need a stance of problem-fixing,
not just problem-avoidance.
And it's true that an ounce of prevention equals a pound of cure,
but that's only if we know what to prevent.
If you've been punched on the nose,
then the science of medicine does not consist of teaching you
how to avoid punches.
(Laughter)
If medical science stopped seeking cures and concentrated on prevention only,
then it would achieve very little of either.
The world is buzzing at the moment
with plans to force reductions in gas emissions at all costs.
It ought to be buzzing with plans to reduce the temperature,
and with plans to live at the higher temperature --
and not at all costs, but efficiently and cheaply.
And some such plans exist,
things like swarms of mirrors in space to deflect the sunlight away,
and encouraging aquatic organisms to eat more carbon dioxide.
At the moment, these things are fringe research;
they're not central to the human effort to face this problem,
or problems in general.
And with problems that we are not aware of yet,
the ability to put right -- not the sheer good luck of avoiding indefinitely --
is our only hope, not just of solving problems,
but of survival.
So take two stone tablets, and carve on them.
On one of them, carve: "Problems are soluble."
And on the other one, carve: "Problems are inevitable."
Thank you.
(Applause)