请双击下面的英文字幕来播放视频。
翻译人员: Sanqiang Xiao
校对人员: Bangyou Xiang
00:12
Every day we face issues like climate change
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每天,我们都面对着像气候变化或
00:16
or the safety of vaccines
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疫苗安全这样的问题,
00:17
where we have to answer questions whose answers
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而对这些问题的解答
00:20
rely heavily on scientific information.
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都仰仗于科学知识。
00:23
Scientists tell us that the world is warming.
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科学家告诉我们世界正在变暖。
00:26
Scientists tell us that vaccines are safe.
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科学家告诉我们疫苗是安全的。
00:29
But how do we know if they are right?
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但我们怎么知道他们说的是对的呢?
00:31
Why should be believe the science?
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为什么我们要相信科学呢?
00:33
The fact is, many of us actually
don't believe the science.
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事实是,我们中的大多数人
实际上不相信科学。
00:36
Public opinion polls consistently show
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民意调查一贯表明,
00:39
that significant proportions of the American people
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有相当一部分美国人
00:42
don't believe the climate is
warming due to human activities,
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不相信气候正在变暖是由于人类活动,
00:45
don't think that there is
evolution by natural selection,
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不相信有自然选择的生物演化,
00:48
and aren't persuaded by the safety of vaccines.
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并且不相信疫苗的安全性。
00:52
So why should we believe the science?
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那么我们为什么要相信科学呢?
00:56
Well, scientists don't like talking about
science as a matter of belief.
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好吧,科学家并不喜欢把
科学当作一种信念来讨论。
00:59
In fact, they would contrast science with faith,
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事实上,他们会把科学与信仰相对,
01:02
and they would say belief is the domain of faith.
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并且会说信念是信仰的一部分。
01:05
And faith is a separate thing
apart and distinct from science.
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而信仰是一个处在科学之外,
与其截然不同的东西。
01:09
Indeed they would say religion is based on faith
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事实上他们会说宗教是基于信仰的,
01:12
or maybe the calculus of Pascal's wager.
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或是基于帕斯卡赌注的演算。
01:15
Blaise Pascal was a 17th-century mathematician
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布莱兹·帕斯卡是一位17世纪的数学家,
01:18
who tried to bring scientific
reasoning to the question of
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他试着将科学的论证引入
01:21
whether or not he should believe in God,
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他是否该信仰上帝这一问题,
01:23
and his wager went like this:
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他的赌注如下:
01:25
Well, if God doesn't exist
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好吧,如果上帝不存在,
01:28
but I decide to believe in him
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但我决定信仰他,
01:30
nothing much is really lost.
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没有什么大的损失。
01:32
Maybe a few hours on Sunday.
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也许只是周日要花掉几个小时。
01:34
(Laughter)
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(众人笑。)
(译注:基督教周日礼拜。)
01:35
But if he does exist and I don't believe in him,
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但如果他存在但我不信仰他,
01:38
then I'm in deep trouble.
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那我就有很大的麻烦了。
01:40
And so Pascal said, we'd better believe in God.
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所以帕斯卡说我们最好相信上帝,
01:43
Or as one of my college professors said,
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或者像我的一个大学教授所说,
01:45
"He clutched for the handrail of faith."
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“他紧紧抓住了信仰的扶手。”
01:47
He made that leap of faith
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帕斯卡最终选择了信仰,
01:49
leaving science and rationalism behind.
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放下了科学与理性。
01:54
Now the fact is though, for most of us,
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事实是对我们中的大多数人,
01:56
most scientific claims are a leap of faith.
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大多数科学结论都是一种信仰。
02:00
We can't really judge scientific
claims for ourselves in most cases.
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在大多数时候,
我们并不能亲自验证科学结论。
02:04
And indeed this is actually
true for most scientists as well
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事实上在专业领域之外,
02:07
outside of their own specialties.
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对于大多是科学家来说也是这样。
02:09
So if you think about it, a geologist can't tell you
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所以就算你想知道一个疫苗是否安全,
02:12
whether a vaccine is safe.
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一个地质学家也不能告诉你答案。
02:13
Most chemists are not experts in evolutionary theory.
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大多数化学家也不是进化论的专家。
02:16
A physicist cannot tell you,
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一个物理学家不能告诉你,
02:19
despite the claims of some of them,
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烟草是否致癌,
02:20
whether or not tobacco causes cancer.
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尽管他们中的一些说自己能。
02:24
So, if even scientists themselves
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所以,如果连科学家
02:26
have to make a leap of faith
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在自己的专业领域之外
02:27
outside their own fields,
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都得相信无法感知的结论,
02:29
then why do they accept the
claims of other scientists?
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那么这些科学家为什么要相信
其他科学家的断言呢?
02:33
Why do they believe each other's claims?
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为什么他们要相信彼此的结论?
02:35
And should we believe those claims?
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我们也应该相信这些结论吗?
02:39
So what I'd like to argue is yes, we should,
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所以我的答案是”没错,我们应该相信。“
02:41
but not for the reason that most of us think.
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但不是由于我们大多数人所想的原因。
02:44
Most of us were taught in school
that the reason we should
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学校教诲我们大多数人
02:47
believe in science is because of the scientific method.
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要相信科学是因为那些科学方法。
02:50
We were taught that scientists follow a method
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我们了解到科学家是遵从某种方法,
02:53
and that this method guarantees
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并且这个方法保证了
02:55
the truth of their claims.
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他们结论的正确性。
02:57
The method that most of us were taught in school,
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大多数人在学校学到的这种方法,
03:01
we can call it the textbook method,
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我们称之为教科书方法,
03:02
is the hypothetical deductive method.
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是一种假设性的演绎推理。
03:05
According to the standard
model, the textbook model,
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根据标准的模型,即教科书模型,
03:08
scientists develop hypotheses, they deduce
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科学家发展了假说,
03:11
the consequences of those hypotheses,
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并推理出这些假说的结果,
03:14
and then they go out into the world and they say,
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然后他们对全世界宣称,
03:15
"Okay, well are those consequences true?"
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“好的,这些结果正确吗?”
03:18
Can we observe them taking
place in the natural world?
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我们能够观测到
它们在自然界中发生吗?
03:21
And if they are true, then the scientists say,
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如果它们是正确的,那么科学家说,
03:24
"Great, we know the hypothesis is correct."
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“好的,我们知道假设是正确的。”
03:27
So there are many famous examples in the history
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所以历史上有许多著名的
03:29
of science of scientists doing exactly this.
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关于科学家们做了这件事的例子。
03:32
One of the most famous examples
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最著名的例子之一
03:34
comes from the work of Albert Einstein.
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来自爱因斯坦的工作。
03:36
When Einstein developed the
theory of general relativity,
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当爱因斯坦发展他的广义相对论时,
03:38
one of the consequences of his theory
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理论的一个结果是
03:41
was that space-time wasn't just an empty void
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时空并不是空空如也,
03:44
but that it actually had a fabric.
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而是有一个网状结构。
03:45
And that that fabric was bent
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那种结构会在大质量物体
03:47
in the presence of massive objects like the sun.
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比如太阳的附近弯曲。
03:50
So if this theory were true then it meant that light
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所以如果这个理论是正确的,
03:53
as it passed the sun
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那么当光线经过太阳时,
03:55
should actually be bent around it.
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会在太阳附近被弯曲。
03:57
That was a pretty startling prediction
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这是一个很惊人的预测,
03:59
and it took a few years before scientists
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科学家花了很多年
04:01
were able to test it
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才验证了它,
04:03
but they did test it in 1919,
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但是他们确实在1919年进行了验证,
04:05
and lo and behold it turned out to be true.
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并且结果是正确的。
04:07
Starlight actually does bend
as it travels around the sun.
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星光确实在经过太阳附近时被弯曲。
04:11
This was a huge confirmation of the theory.
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这是对广义相对论的一个重要肯定,
04:13
It was considered proof of the truth
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这被认为是对广义相对论
04:15
of this radical new idea,
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这一新颖理论的证明,
04:16
and it was written up in many newspapers
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这次验证也被全球许多报纸
04:18
around the globe.
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报道了。
04:21
Now, sometimes this theory or this model
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有时候这些理论和模型
04:23
is referred to as the deductive-nomological model,
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被称为演绎-规律模型(D-N模型),
04:26
mainly because academics like
to make things complicated.
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主要是因为学者喜欢让事情复杂化。
04:30
But also because in the ideal case, it's about laws.
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但也是因为在理想状态下,这是法则。
04:35
So nomological means having to do with laws.
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Nomological表示要遵循法则。
04:38
And in the ideal case, the hypothesis isn't just an idea:
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在理想情况下,假说不仅仅是一个想法:
04:41
ideally, it is a law of nature.
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它是自然法则。
04:43
Why does it matter that it is a law of nature?
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为什么自然法则很重要呢?
04:46
Because if it is a law, it can't be broken.
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因为法则不能被打破。
04:48
If it's a law then it will always be true
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法则一定是正确的,
04:50
in all times and all places
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不管何时何地,
04:52
no matter what the circumstances are.
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不管在什么情况下。
04:54
And all of you know of at least
one example of a famous law:
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你们大概都知道一个著名的法则:
04:57
Einstein's famous equation, E=MC2,
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爱因斯坦的著名等式,E=mc^2,
05:01
which tells us what the relationship is
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它告诉了我们能量和
05:03
between energy and mass.
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质量的关系。
05:05
And that relationship is true no matter what.
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这个关系在任何情况下都成立。
05:09
Now, it turns out, though, that there
are several problems with this model.
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但结果表明,
似乎这个模型有一些问题。
05:13
The main problem is that it's wrong.
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最主要的问题就是这个模型是错的。
05:16
It's just not true. (Laughter)
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它不是正确的。
(笑声)
05:20
And I'm going to talk about
three reasons why it's wrong.
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我想讲讲三个原因,
为什么说它是错的。
05:22
So the first reason is a logical reason.
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第一个是逻辑问题。
05:25
It's the problem of the fallacy
of affirming the consequent.
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问题在于荒谬地断定结果。
05:29
So that's another fancy, academic way of saying
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这是另一种幻想,用学术术语称为
05:31
that false theories can make true predictions.
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错误的理论得出正确的预测。
05:34
So just because the prediction comes true
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所以仅仅因为预测是正确的,
05:36
doesn't actually logically
prove that the theory is correct.
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并不能从逻辑上证明理论是正确的。
05:39
And I have a good example of that too,
again from the history of science.
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科学史上有一个很好的例子。
05:43
This is a picture of the Ptolemaic universe
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这是一幅展现托勒密宇宙的图,
05:46
with the Earth at the center of the universe
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地球在宇宙中心,
05:48
and the sun and the planets going around it.
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太阳和行星都围绕它运行。
05:50
The Ptolemaic model was believed
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托勒密模型在多个世纪中
05:52
by many very smart people for many centuries.
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都被很多聪明人所接纳。
05:56
Well, why?
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为什么?
05:57
Well the answer is because it made
lots of predictions that came true.
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因为由它进行的许多预测
都被证明是正确的。
06:01
The Ptolemaic system enabled astronomers
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托勒密系统使得天文学家
06:03
to make accurate predictions
of the motions of the planet,
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对行星运行做出准确的预测,
06:06
in fact more accurate predictions at first
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事实上甚至比哥白尼理论
在最初时更准确,
06:08
than the Copernican theory
which we now would say is true.
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虽然后者现在被公认是正确的。
06:12
So that's one problem with the textbook model.
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所以这是教科书模型的一个问题。
06:15
A second problem is a practical problem,
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第二个问题是一个实际问题,
06:18
and it's the problem of auxiliary hypotheses.
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问题在于辅助假说。
06:21
Auxiliary hypotheses are assumptions
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辅助假说是科学家
06:24
that scientists are making
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做出的假设,
06:26
that they may or may not even
be aware that they're making.
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他们可能甚至没意识到
自己做出了这个假设。
06:29
So an important example of this
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一个很重要的例子是
06:31
comes from the Copernican model,
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哥白尼模型,
06:33
which ultimately replaced the Ptolemaic system.
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它最终取代了托勒密模型。
06:37
So when Nicolaus Copernicus said,
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所以当尼古拉斯哥白尼宣称
06:39
actually the Earth is not the center of the universe,
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事实上地球不是宇宙的中心,
06:41
the sun is the center of the solar system,
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太阳是太阳系的中心,
06:43
the Earth moves around the sun.
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地球围绕着太阳旋转,
06:45
Scientists said, well okay, Nicolaus, if that's true
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科学家说,好吧,尼古拉斯,
如果这是对的,
06:48
we ought to be able to detect the motion
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我们应该能检测出地球围绕
06:50
of the Earth around the sun.
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太阳的运动。
06:52
And so this slide here illustrates a concept
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这一页幻灯片展示了这个概念,
06:54
known as stellar parallax.
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叫做星球视差。
06:56
And astronomers said, if the Earth is moving
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天文家说,如果地球是运动的
07:00
and we look at a prominent star, let's say, Sirius --
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我们关注一个显眼的星星,
比如天狼星——
07:03
well I know I'm in Manhattan
so you guys can't see the stars,
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在曼哈顿可能看不到这颗星星,
07:05
but imagine you're out in the country,
imagine you chose that rural life —
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但想象你在乡村,你过着田园生活,
07:09
and we look at a star in December, we see that star
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在十二月我们看着那个星星,
07:12
against the backdrop of distant stars.
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以其他遥远的星星做背景。
07:15
If we now make the same observation six months later
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而六个月之后,
如果我们做同样的观察,
07:18
when the Earth has moved to this position in June,
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在六月,地球已经移动到了这个位置,
07:22
we look at that same star and we
see it against a different backdrop.
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我们观察同样的星星
应该看到不同的背景。
07:26
That difference, that angular
difference, is the stellar parallax.
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这个视角的差异被称为星球视差。
07:30
So this is a prediction that the Copernican model makes.
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这就是哥白尼模型做出的预测。
07:33
Astronomers looked for the stellar parallax
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天文学家想找到星球视差,
07:35
and they found nothing, nothing at all.
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但他们找不到任何差异。
07:40
And many people argued that this proved
that the Copernican model was false.
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许多人称这证明了哥白尼模型
是错误的。
07:44
So what happened?
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怎么回事呢?
07:46
Well, in hindsight we can say
that astronomers were making
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事后我们能说天文学家
07:48
two auxiliary hypotheses, both of which
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做出了两个假设,
07:51
we would now say were incorrect.
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现在被公认都是错误的。
07:53
The first was an assumption
about the size of the Earth's orbit.
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第一个是关于地球轨道大小的假设。
07:57
Astronomers were assuming
that the Earth's orbit was large
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天文学家假定地球的轨道很大,
08:00
relative to the distance to the stars.
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相较于星星的距离。
08:02
Today we would draw the picture more like this,
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今天我们会画出一个这样的图案
08:05
this comes from NASA,
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来自NASA。
08:06
and you see the Earth's orbit is actually quite small.
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可以看到地球的轨道非常小。
08:09
In fact, it's actually much
smaller even than shown here.
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事实上可能比这显示的更小。
08:12
The stellar parallax therefore,
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因此,星球视差
08:13
is very small and actually very hard to detect.
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会非常小,而且难以探测。
08:17
And that leads to the second reason
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这也引出了另一个原因,
08:19
why the prediction didn't work,
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为什么这个预测不准确。
08:21
because scientists were also assuming
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因为科学家也假定
08:23
that the telescopes they had were sensitive enough
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他们的天文望远镜足够灵敏,
08:26
to detect the parallax.
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足以检测到这个视差。
08:27
And that turned out not to be true.
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后来证明是错的。
08:29
It wasn't until the 19th century
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直到19世纪
08:32
that scientists were able to detect
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科学家才能检测出
08:34
the stellar parallax.
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星球视差。
08:35
So, there's a third problem as well.
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还有第三个问题。
08:38
The third problem is simply a factual problem,
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这是现实问题,
08:41
that a lot of science doesn't fit the textbook model.
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许多的科学不适用教科书模型。
08:43
A lot of science isn't deductive at all,
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许多的科学根本不是演绎,
08:46
it's actually inductive.
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而是归纳出来的。
08:48
And by that we mean that scientists don't necessarily
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这样的话,科学家并不需要
08:50
start with theories and hypotheses,
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由理论和假设出发,
08:52
often they just start with observations
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通常他们只是从观察出发,
08:54
of stuff going on in the world.
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观察世界上的的一切。
08:57
And the most famous example
of that is one of the most
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最著名的例子是
08:59
famous scientists who ever lived, Charles Darwin.
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最著名的科学家,查尔斯·达尔文。
09:02
When Darwin went out as a young
man on the voyage of the Beagle,
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当达尔文还年轻,在比格号上航行时,
09:05
he didn't have a hypothesis, he didn't have a theory.
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他没有假设,他没有理论。
09:09
He just knew that he wanted
to have a career as a scientist
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他只知道他希望成为科学家,
09:12
and he started to collect data.
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他开始收集数据。
09:14
Mainly he knew that he hated medicine
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主要是因为他讨厌医学,
09:17
because the sight of blood made him sick so
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因为他晕血,
09:19
he had to have an alternative career path.
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所以他必须选择另一条职业道路。
09:21
So he started collecting data.
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所以他开始收集数据。
09:23
And he collected many things,
including his famous finches.
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他收集许多的东西,
包括他著名的雀鸟。
09:26
When he collected these finches,
he threw them in a bag
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他收集这些雀鸟的时候,
会把它们扔到袋子里,
09:28
and he had no idea what they meant.
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他并不知道它们意味着什么。
09:31
Many years later back in London,
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许多年以后回到伦敦时,
09:33
Darwin looked at his data again and began
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达尔文再次翻看他的数据,
09:35
to develop an explanation,
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开始做出了一些解释,
09:38
and that explanation was the
theory of natural selection.
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这个解释就是自然选择论。
09:41
Besides inductive science,
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除了归纳科学,
09:43
scientists also often participate in modeling.
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科学家也常常进行建模。
09:46
One of the things scientists want to do in life
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他们一生中最想做的事情
09:48
is to explain the causes of things.
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就是解释事情的起因。
09:51
And how do we do that?
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我们怎么做呢?
09:52
Well, one way you can do it is to build a model
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建立模型是一个方法,
09:54
that tests an idea.
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可以用来测试一个想法。
09:56
So this is a picture of Henry Cadell,
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这是亨利卡德尔的照片,
09:58
who was a Scottish geologist in the 19th century.
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他是19世纪的苏格兰地理学家。
10:01
You can tell he's Scottish because he's wearing
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从服饰可以看出他是一个苏格兰人,
10:02
a deerstalker cap and Wellington boots.
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猎鹿帽和威林顿靴。
10:05
(Laughter)
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(笑声)
10:07
And Cadell wanted to answer the question,
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卡德尔希望能回答这个问题,
10:08
how are mountains formed?
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山是怎么形成的?
10:10
And one of the things he had observed
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他观察到的一个事情是,
10:12
is that if you look at mountains
like the Appalachians,
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如果你注视山,比如阿帕拉契山脉时,
10:14
you often find that the rocks in them
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你会发现山中的石头
10:16
are folded,
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是叠层的,
10:17
and they're folded in a particular way,
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它们由特定的方式堆叠而成,
10:19
which suggested to him
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这显示
10:20
that they were actually being
compressed from the side.
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它们是由两侧挤压而成的。
10:23
And this idea would later play a major role
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这个想法在之后的
10:25
in discussions of continental drift.
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大陆漂移假说中扮演了重要角色。
10:28
So he built this model, this crazy contraption
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2506
所以他建造了这个模型,
这个疯狂的装置,
10:30
with levers and wood, and here's his wheelbarrow,
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2152
有杠杆、木头、独轮车、
10:33
buckets, a big sledgehammer.
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木桶、大锤子,
10:35
I don't know why he's got the Wellington boots.
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1898
我不知道他什么要穿威林顿靴。
10:37
Maybe it's going to rain.
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也许要下雨了吧。
10:38
And he created this physical model in order
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他建造了这个实物模型,
10:42
to demonstrate that you could, in fact, create
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用来证明你事实上能在石头上,
10:46
patterns in rocks, or at least, in this case, in mud,
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或至少像这样在泥土上制造
10:48
that looked a lot like mountains
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山石那样的纹路,
10:50
if you compressed them from the side.
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1842
只需要从侧面挤压它们。
10:52
So it was an argument about
the cause of mountains.
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这是关于山体形成的论证。
10:56
Nowadays, most scientists prefer to work inside,
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如今,科学家们更希望
进行深入的研究,
10:59
so they don't build physical models so much
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他们并不常常建立实物模型,
11:01
as to make computer simulations.
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而是用计算机模拟。
11:04
But a computer simulation is a kind of a model.
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但计算机模拟仅仅是一个模型。
11:07
It's a model that's made with mathematics,
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一个数学模型,
11:08
and like the physical models of the 19th century,
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正如19世纪的实物模型一样,
11:12
it's very important for thinking about causes.
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思考起因是非常重要的。
11:15
So one of the big questions
to do with climate change,
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所以应对气候变化最重要的问题就是,
11:18
we have tremendous amounts of evidence
257
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1803
我们有大量的证据表明
11:20
that the Earth is warming up.
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地球正在升温。
11:22
This slide here, the black line shows
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这页幻灯片中,黑色的线条显示
11:24
the measurements that scientists have taken
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科学家们测量的
11:26
for the last 150 years
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1963
过去150年的统计结果,
11:28
showing that the Earth's temperature
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1410
显示了地球的温度
11:30
has steadily increased,
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1634
正在稳步升高,
11:31
and you can see in particular
that in the last 50 years
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2846
尤其是最近的50年
11:34
there's been this dramatic increase
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上升是显著的,
11:36
of nearly one degree centigrade,
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2340
几乎是1摄氏度,
11:38
or almost two degrees Fahrenheit.
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或2华氏度。
11:41
So what, though, is driving that change?
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那么是什么驱动了这个改变呢?
11:43
How can we know what's causing
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我们怎么知道是什么导致了
11:45
the observed warming?
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这么明显的升温呢?
11:47
Well, scientists can model it
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1714
科学家可以建模,
11:49
using a computer simulation.
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用计算机进行模拟。
11:51
So this diagram illustrates a computer simulation
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2792
这张图展示了计算机模拟,
11:54
that has looked at all the different factors
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考虑了各种
11:56
that we know can influence the Earth's climate,
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2605
可能影响地球气候的因素,
11:59
so sulfate particles from air pollution,
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2752
从空气污染中的硫酸盐颗粒,
12:01
volcanic dust from volcanic eruptions,
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到火山喷发中的火山灰,
12:04
changes in solar radiation,
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到太阳辐射的改变,
12:07
and, of course, greenhouse gases.
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2378
当然,还有温室气体。
12:09
And they asked the question,
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他们问了这样一个问题,
12:11
what set of variables put into a model
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3696
在模型中加入什么样的变量
12:14
will reproduce what we actually see in real life?
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能再现我们在真实生活中
看到的情况呢?
12:17
So here is the real life in black.
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2020
黑线表示真实观察的数据,
12:19
Here's the model in this light gray,
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浅灰色表示模拟的数据,
12:22
and the answer is
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答案是
12:23
a model that includes, it's the answer E on that SAT,
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4387
在上述的模拟中加入SAT考试中的E,
12:28
all of the above.
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2141
也就是以上皆有。
(译注:SAT考试中最常见答案)
12:30
The only way you can reproduce
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1506
能再现所观察到的
12:31
the observed temperature measurements
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1828
温度测量数据的唯一的方法,
12:33
is with all of these things put together,
290
753602
1978
就是把所有的东西放到一起,
12:35
including greenhouse gases,
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2139
包括温室气体,
12:37
and in particular you can see that the increase
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2551
特别是我们可以观察到
12:40
in greenhouse gases tracks
293
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1884
在对温室气体数据
12:42
this very dramatic increase in temperature
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2206
追踪时显示温度的上升,
12:44
over the last 50 years.
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在过去的50年非常明显。
12:45
And so this is why climate scientists say
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2434
所以这就是为什么气候学家称
12:48
it's not just that we know that
climate change is happening,
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我们不仅仅知道气候变化正在发生,
12:51
we know that greenhouse gases are a major part
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2768
我们还知道温室气体是主要的
12:54
of the reason why.
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影响因素。
12:56
So now because there all these different things
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2388
由于科学家做的这些
12:59
that scientists do,
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各种各样的事情,
13:00
the philosopher Paul Feyerabend famously said,
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3486
哲学家保罗·费耶阿本德
说过一句名言,
13:04
"The only principle in science
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1626
“在不影响进步的情况下,
13:05
that doesn't inhibit progress is: anything goes."
304
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3979
科学界唯一个法则就是:
任何方法都可以。”
13:09
Now this quotation has often
been taken out of context,
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2616
这句名言经常被断章取义,
13:12
because Feyerabend was not actually saying
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2118
因为费耶阿本德并不是说
13:14
that in science anything goes.
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1950
在科学上怎么都行。
13:16
What he was saying was,
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1344
他想说的
13:17
actually the full quotation is,
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2024
完整版的话应该是,
13:19
"If you press me to say
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2090
“如果你强制我说出
13:21
what is the method of science,
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科学研究方法是什么,
13:23
I would have to say: anything goes."
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3629
我会说:任何方法都可以。"
13:27
What he was trying to say
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1078
他想要说的应该是
13:28
is that scientists do a lot of different things.
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2567
科学家做了许多不同的事情。
13:30
Scientists are creative.
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2308
科学家很有创造力。
13:33
But then this pushes the question back:
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2110
但这个问题又回来了,
13:35
If scientists don't use a single method,
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3471
如果科学家不用一种统一的方法,
13:38
then how do they decide
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1899
他们怎么决定
13:40
what's right and what's wrong?
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1458
什么是正确的或者错误的?
13:42
And who judges?
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1894
由谁来决定呢?
13:44
And the answer is, scientists judge,
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答案是,由科学家决定,
13:46
and they judge by judging evidence.
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他们依照证据决定。
13:49
Scientists collect evidence in many different ways,
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3409
科学家通过不同的方法收集证据,
13:52
but however they collect it,
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1622
但不论他们如何收集,
13:54
they have to subject it to scrutiny.
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2577
他们要审慎看待这些证据。
13:56
And this led the sociologist Robert Merton
326
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2560
这就导致了社会学家罗伯特 · 默顿
13:59
to focus on this question of how scientists
327
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2180
关注这样一个问题,即科学家该如何
14:01
scrutinize data and evidence,
328
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1679
审慎看待他们的证据和数据,
14:03
and he said they do it in a way he called
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2808
他将这种方法称之为
14:05
"organized skepticism."
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1919
“组织性怀疑”。
14:07
And by that he meant it's organized
331
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1884
“组织性”说明
14:09
because they do it collectively,
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1478
科学家合作收集数据,
14:11
they do it as a group,
333
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1629
他们作为团队一起工作,
14:12
and skepticism, because they do it from a position
334
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2816
“怀疑”说明他们对证据
14:15
of distrust.
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1454
持怀疑态度。
14:17
That is to say, the burden of proof
336
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1962
这就是说,关于证据的主要工作
14:18
is on the person with a novel claim.
337
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2481
落在了宣称自己
发现了新东西的人身上。
14:21
And in this sense, science
is intrinsically conservative.
338
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3143
在这种情况下,科学的本质是保守。
14:24
It's quite hard to persuade the scientific community
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2572
想要说服科学界
14:27
to say, "Yes, we know something, this is true."
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3711
称“我们发现了些东西,这是真的”很难。
14:30
So despite the popularity of the concept
341
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2496
尽管方式转变的观念
14:33
of paradigm shifts,
342
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1597
被广泛地接受,
14:34
what we find is that actually,
343
874990
1284
我们却发现
14:36
really major changes in scientific thinking
344
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2785
科学思维上的重要改变
14:39
are relatively rare in the history of science.
345
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3720
在科学史上十分罕见。
14:42
So finally that brings us to one more idea:
346
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3563
最后我们提出了另一个想法:
14:46
If scientists judge evidence collectively,
347
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3708
如果科学家集体评判证据,
14:50
this has led historians to focus on the question
348
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2562
这就导致历史学家聚焦在了
14:52
of consensus,
349
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1419
“共识”这一问题上,
14:54
and to say that at the end of the day,
350
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1895
在最后,
14:55
what science is,
351
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1934
什么是科学,
14:57
what scientific knowledge is,
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1670
科学知识是什么,
14:59
is the consensus of the scientific experts
353
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3379
这是科学专家达成的共识,
15:02
who through this process of organized scrutiny,
354
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2154
他们通过这种组织性的怀疑,
15:05
collective scrutiny,
355
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2305
合作的怀疑,
15:07
have judged the evidence
356
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1242
来评判证据
15:08
and come to a conclusion about it,
357
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2797
得出结论,
15:11
either yea or nay.
358
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2477
判断正误,
15:13
So we can think of scientific knowledge
359
913884
1724
所以我们可以认为科学知识
15:15
as a consensus of experts.
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2052
就是专家的共识。
15:17
We can also think of science as being
361
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1772
我们也能认为科学是
15:19
a kind of a jury,
362
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1578
一种陪审团下的产物,
15:21
except it's a very special kind of jury.
363
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2514
当然这个陪审团非常特别。
15:23
It's not a jury of your peers,
364
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2104
他们不是你的同辈组成的,
15:25
it's a jury of geeks.
365
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1896
他们是怪才组成的陪审团。
15:27
It's a jury of men and women with Ph.D.s,
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3634
他们是由男博士女博士组成的,
15:31
and unlike a conventional jury,
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不同于传统的陪审团
15:33
which has only two choices,
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1690
只有两种选择,
15:35
guilty or not guilty,
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2685
有罪或无罪,
15:37
the scientific jury actually has a number of choices.
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3401
科学陪审团有很多的选择。
15:41
Scientists can say yes, something's true.
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2784
科学家们能说,这是对的。
15:44
Scientists can say no, it's false.
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2580
他们能说,这是错的。
15:46
Or, they can say, well it might be true
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2540
他们也能说,这可能是对的,
15:49
but we need to work more
and collect more evidence.
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3044
但我们需要更多的证据。
15:52
Or, they can say it might be true,
375
952324
1616
他们也能说,这可能是对的,
15:53
but we don't know how to answer the question
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953940
1700
但我们不知道如何回答这个问题,
15:55
and we're going to put it aside
377
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1310
可以先放在一边,
15:56
and maybe we'll come back to it later.
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2923
之后再讨论。
15:59
That's what scientists call "intractable."
379
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4002
他们称这种情况“很棘手”。
16:03
But this leads us to one final problem:
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2606
但这把我们引向另一个问题:
16:06
If science is what scientists say it is,
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2938
如果科学是科学家定义的,
16:09
then isn't that just an appeal to authority?
382
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2541
那这是不是只诉诸权威呢?
16:11
And weren't we all taught in school
383
971960
1062
我们不是在学校学过,
16:13
that the appeal to authority is a logical fallacy?
384
973022
3227
诉诸权威是逻辑上的谬误吗?
16:16
Well, here's the paradox of modern science,
385
976249
3032
其实这是现代科学的悖论,
16:19
the paradox of the conclusion I think historians
386
979281
2272
我相信历史学家、
16:21
and philosophers and sociologists have come to,
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2601
哲学家和社会学家都会得出来的悖论,
16:24
that actually science is the appeal to authority,
388
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3501
事实上科学就是诉诸权威,
16:27
but it's not the authority of the individual,
389
987655
3776
但这不是对个人的权威,
16:31
no matter how smart that individual is,
390
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2399
不论这个人有多聪明,
16:33
like Plato or Socrates or Einstein.
391
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3865
像柏拉图,苏格拉底或爱因斯坦。
16:37
It's the authority of the collective community.
392
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3114
这是对精英群体的权威。
16:40
You can think of it is a kind of wisdom of the crowd,
393
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2986
你可以把它理解成一种集体智慧,
16:43
but a very special kind of crowd.
394
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4126
但这个集体非常特别。
16:47
Science does appeal to authority,
395
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1890
科学确实诉诸权威,
16:49
but it's not based on any individual,
396
1009811
2050
但不是诉诸个人,
16:51
no matter how smart that individual may be.
397
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2586
不论这个人多聪明。
16:54
It's based on the collective wisdom,
398
1014447
1751
它建立于集体智慧之上,
16:56
the collective knowledge, the collective work,
399
1016198
2642
建立于集体知识,集体工作之上,
16:58
of all of the scientists who have worked
400
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1898
建立于为这个问题努力过的
17:00
on a particular problem.
401
1020738
2717
所有科学家之上。
17:03
Scientists have a kind of culture of collective distrust,
402
1023455
2796
科学家有一种集体怀疑的文化,
17:06
this "show me" culture,
403
1026251
2200
这就是“给我看”文化,
17:08
illustrated by this nice woman here
404
1028451
1950
这个女士向我们展示了这一点,
17:10
showing her colleagues her evidence.
405
1030401
3082
她在向她的同事展示她的证据。
17:13
Of course, these people don't
really look like scientists,
406
1033483
1857
当然,这些人并不像科学家,
17:15
because they're much too happy.
407
1035340
1986
他们看起来太开心了。
17:17
(Laughter)
408
1037326
4012
(笑声)
17:21
Okay, so that brings me to my final point.
409
1041338
4322
最后,我想说:
17:25
Most of us get up in the morning.
410
1045660
2648
我们大多数人要早起奔波。
17:28
Most of us trust our cars.
411
1048308
1410
大多数人依赖我们的汽车。
17:29
Well, see, now I'm thinking, I'm in Manhattan,
412
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1542
瞧,我现在在曼哈顿,
17:31
this is a bad analogy,
413
1051260
1298
这不是一个很好的类比,
17:32
but most Americans who don't live in Manhattan
414
1052558
2824
但大多数美国人没住在曼哈顿,
17:35
get up in the morning and get in their cars
415
1055382
1738
早上起来,钻进汽车,
17:37
and turn on that ignition, and their cars work,
416
1057120
2529
点火,汽车就运转了,
17:39
and they work incredibly well.
417
1059649
2001
运转得相当不错。
17:41
The modern automobile hardly ever breaks down.
418
1061650
2715
现代的汽车基本不怎么抛锚。
17:44
So why is that? Why do cars work so well?
419
1064365
2783
为什么呢?
为什么车能运行得这么好?
17:47
It's not because of the genius of Henry Ford
420
1067148
2504
这不是因为亨利·福特的天才,
17:49
or Karl Benz or even Elon Musk.
421
1069652
3091
也不是卡尔·奔驰或伊隆·马斯克。
17:52
It's because the modern automobile
422
1072743
2142
这是因为现代的汽车
17:54
is the product of more than 100 years of work
423
1074885
5034
是100多年努力的结晶,
17:59
by hundreds and thousands
424
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1590
是成百上千,
18:01
and tens of thousands of people.
425
1081509
1336
甚至上万人的努力。
18:02
The modern automobile is the product
426
1082845
2111
现代汽车是
18:04
of the collected work and wisdom and experience
427
1084956
2789
集体工作和智慧及经验的产物,
18:07
of every man and woman who has ever worked
428
1087745
2347
是所有为汽车工作过的
18:10
on a car,
429
1090092
1608
男人和女人的产物,
18:11
and the reliability of the technology is the result
430
1091700
2915
这项技术的可靠性就是
18:14
of that accumulated effort.
431
1094615
2683
这些付出加起来的结果。
18:17
We benefit not just from the genius of Benz
432
1097298
2857
我们不仅仅从奔驰,福特和马斯克的
18:20
and Ford and Musk
433
1100155
1066
天才中获益,
18:21
but from the collective intelligence and hard work
434
1101221
2768
而是从所有为现代汽车
18:23
of all of the people who have worked
435
1103989
2251
奋斗的人们的
18:26
on the modern car.
436
1106240
1670
集体智慧和工作中获益。
18:27
And the same is true of science,
437
1107910
2050
科学界也一样,
18:29
only science is even older.
438
1109960
2844
只是科学更加古老。
18:32
Our basis for trust in science is actually the same
439
1112804
2574
我们信任科学的基石,
18:35
as our basis in trust in technology,
440
1115378
2674
与我们信任技术的基石是一样的,
18:38
and the same as our basis for trust in anything,
441
1118052
3987
与我们信任其他事物的基石
都是一样的,
18:42
namely, experience.
442
1122039
2278
也就是,经验。
18:44
But it shouldn't be blind trust
443
1124317
1844
但这不应该是盲目的信任,
18:46
any more than we would have blind trust in anything.
444
1126161
2760
不能盲目信任任何事情。
18:48
Our trust in science, like science itself,
445
1128921
2841
我们对科学的信任如同科学本身,
18:51
should be based on evidence,
446
1131762
1913
应该建立于证据,
18:53
and that means that scientists
447
1133675
1502
这意味着科学家
18:55
have to become better communicators.
448
1135177
2048
应该善于沟通。
18:57
They have to explain to us not just what they know
449
1137225
2887
他们不仅必须向我们
解释他们知道的东西,
19:00
but how they know it,
450
1140112
1728
还要解释他们知道的过程,
19:01
and it means that we have
to become better listeners.
451
1141840
3890
这意味着我们需要变为更好的聆听者。
19:05
Thank you very much.
452
1145730
1419
十分感谢。
19:07
(Applause)
453
1147149
2303
(鼓掌)
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