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加里,你竟然敢请一位人工智能领域的诺贝尔奖得主来告诉我们,我们都要完蛋了?
Gary, you had the audacity to bring in a Nobel Laureate expert in AI to tell us we're all gonna die?
当然了。
Well, of course.
实际上,我们只需要问一下人工智能就行了。
Actually, all we had to do was ask AI.
接下来是StarTalk特别版:人工智能将是文明的终结还是新生。
Coming up, StarTalk special edition, how AI will be the death or the birth of civilization.
马上为您呈现。
Coming right up.
欢迎收看StarTalk。
Welcome to StarTalk.
这里是科学与流行文化交汇的地方。
Your place in the universe where science and pop culture collide.
StarTalk现在正式开始。
StarTalk begins right now.
这是StarTalk特别版。
This is StarTalk Special Edition.
尼尔·德葛拉司·泰森,你的专属天体物理学家。
Neil deGrasse Tyson, your personal astrophysicist.
如果是特别版,那就意味着我们请来了加里·奥雷利。
And if it's special edition, it means we've got Gary O'Reilly.
嘿,尼尔。
Hey, Neil.
加里。
Gary.
你怎么样
How are
啊,老兄?
doing, man?
我很好。
I'm good.
前职业足球运动员。
Former soccer pro.
是的。
Yes.
所以,查克,很高兴你总是来。
So, Chuck, always good to have you.
总是很愉快。
Always a pleasure.
所以,加里,你和你的团队今天选了一个堪称经典的议题。
So, Gary, you and your team picked a topic for the ages today.
是的。
Yeah.
就是‘是的’。
It's Yeah.
这是我们经常听到的事情。
It's one of those things that we hear about it.
我们以为自己了解它。
We think we know about it.
但让我这样跟你说。
But let me put it to you this way.
我们面临一个简单的事实:如今人工智能已经
We are faced with the simple fact that AI at this point We're
今天我们要谈谈人工智能。
gonna talk about AI today.
是的,我们要。
We are.
好的。
Okay.
这是无法回避的。
It's inescapable.
深入探讨一下?
A deep dive?
哦,
Oh,
是的。
yeah.
对。
Yes.
说吧。
Go.
没错。
Right.
它曾经是
It was
就在几年前,我们问人们人工智能是如何工作的。
only a few years ago when we asked people how AI works.
他们会说,它利用了深度学习和神经网络。
They'll say something along the lines of it utilizes deep learning, neural networks.
但那个流行词。
But That that buzzword.
是的。
Yeah.
他们会随意抛出这些词。
They'll toss them out.
他们知道这些词,但对它们一无所知。
They know them, but they don't know anything about them.
嗯。
Mhmm.
那到底意味着什么?
So what does that really mean?
我们将深入剖析人工智能的工作原理,从最基本的比特层面入手,并探讨我们对人工智能未来发展的看法,来自人工智能奠基人之一的观点。
We'll break down how AI works down to the bit and get into how far we think this is going to go from one of AI's founding architects.
哦。
Oh.
是的
Yes.
不
No.
这值得重视了,我们现在才真正说到点子上。
That's worthy of new Now we're talking.
嗯
Mhmm.
那么,请欢迎我们的嘉宾。
So if you would bring on our guest.
我很乐意。
I'll be delighted to.
我们今天邀请到了杰弗里·辛顿教授。
We have with us professor Geoffrey Hinton.
杰弗里,欢迎来到《星谈》。
Geoffrey, welcome to StarTalk.
谢谢您邀请我。
Thank you for inviting me.
是的。
Yeah.
您是一位认知心理学家和计算机科学家。
You are a cognitive psychologist and computer scientist.
我不认识其他有这种组合的人。
I don't know anybody with that combo.
拿不定主意吗。
Couldn't make up your mind.
您是多伦多大学计算机科学系的荣誉教授。
You're a professor emeritus at the Department of Computer Science at the University of Toronto.
而且,您是OGAI。
And, you are OGAI.
哦,真好。
Oh, lovely.
我能这么说吗?
Can I say that?
那样说会
That that make
听起来像OG AI。
sounds OG AI.
OGAI。
OGAI.
有些人称你为人工智能之父。
And some people have called you the godfather of AI, of artificial intelligence.
让我们直接从头说起。
And let's just go straight out off the top here.
当我们思考当前人工智能的起源时,感觉大型语言模型突然席卷了所有人。
When we think of the genesis of AI as it is currently manifested, it feels like large language models took everybody by storm.
它们突然出现,让所有人都震惊、欢呼、在街头跳舞,或躲在枕头上哭泣。
They just showed up and everybody was freaking out, celebrating, dancing in the streets, or crying in their pillows.
这件事发生在几年前,我们注意到了。
That happened, we noticed a couple of years ago.
所以我只是想知道,很多年前是什么促使你走上这条道路的?
So I'm just wondering what got you started in on this path many, many years ago?
我的研究可以追溯到上世纪九十年代。
My record show goes back to the nineteen nineties.
对吗?
Is that correct?
不对。
No.
其实可以追溯到上世纪五十年代。
It really goes back to the nineteen fifties.
哦。
Oh.
对吧?
Right?
人工智能的创始人在二十世纪五十年代初期,对于如何构建智能系统有两种观点。
The founders of AI, at the beginning in the nineteen fifties, there were two views of how to make an intelligent system.
一种是受逻辑启发的。
One was inspired by logic.
他们的想法是,智能的本质在于推理。
The idea was that the essence of intelligence is reasoning.
而在推理中,你会从一些前提开始,运用一些操作表达式的规则,推导出一些结论。
And in reasoning, what you do is you take some premises, you take some rules for manipulating expressions, and you derive some conclusions.
这很像数学,你有一个方程,有规则告诉你如何操作等式的两边,或者合并方程,从而推导出新的方程。
So it's much like mathematics, where you have an equation, you have rules for how you can tinker with both sides and or combine equations, and you derive new equations.
这就是他们当时所秉持的范式。
And that was kind of the paradigm they had.
还有一种完全不同的范式是生物学的,这种范式认为:我们所知的智能体都有大脑。
There was a completely different paradigm that was biological, and that paradigm said, look, the intelligent things we know have brains.
我们必须弄清楚大脑是如何工作的,而它们的工作方式非常擅长诸如感知之类的事情。
We have to figure out how brains work, and the way they work is they're very good at things like perception.
它们在类比推理方面相当出色。
They're quite good at reasoning by analogy.
它们在逻辑推理方面并不擅长。
They're not much good at reasoning.
你得等到青春期才能真正做好推理。
You have to get to be a teenager before you can do reasoning really.
所以我们应该好好研究它们做的其他事情,弄清楚大规模的脑细胞网络是如何实现感知和记忆等能力的。
So we should really study these other things they do, and we should figure out how big networks of brain cells can do these other things like perception and memory.
当时有少数人支持这种观点,其中就包括约翰·冯·诺依曼和艾伦·图灵。
Now a few people believed in that approach, and among those few people were John von Neumann and Alan Turing.
不幸的是,他们都英年早逝,图灵可能是被英国情报机构害死的。
Unfortunately, they both died young, Turing possibly with the help of British intelligence.
图灵是那部电影的主角,当然。
Turing, he's the subject of the film Of course.
《模仿游戏》。
The Imitation Game.
嗯嗯。
Mhmm.
是的。
Yeah.
对。
Yeah.
所以如果有人还没看过,一定要把它加到你的观影清单里。
So anyone hasn't seen that, definitely put that on your list.
不错。
Cool.
好。
Yeah.
那我要回到二十世纪五十年代吗?
So I would you go back to the nineteen fifties?
那时候你还只是个小孩子。
You were just a young tyke then.
对吧?
Correct?
是的。
Yeah.
那时候我还没满十岁。
I was in single digits then.
我当时还没满十岁。
I was in single digits.
好的。
Okay.
那我们如何追溯你对这个领域好奇心的起源呢?
So how do we establish the genesis of your curiosity in this field?
有几件事。
A few things.
在20世纪60年代初或中期,我在上高中时,有一个非常聪明的朋友,他是个数学天才,而且读很多书。
When I was at high school in the early 1960s or mid 1960s, I had a very smart friend who was a brilliant mathematician and used to read a lot.
有一天,他来学校跟我谈了一个想法,认为记忆可能分布在多个脑细胞中,而不是集中在单个脑细胞里。
And he came into school one day and talked to me about the idea that memories might be distributed over many brain cells instead of in individual brain cells.
这个想法受到了全息图的启发。
So that was inspired by holograms.
当时全息技术刚刚兴起。
Holograms were just coming out then.
加布尔当时很活跃。
Gaboor was active.
因此,分布式记忆这个想法让我非常着迷,从那时起,我就一直在思考大脑是如何存储记忆以及它究竟是如何运作的。
And so the idea of distributed memory got me very interested, and ever since then, I've been wondering how the brain stores memories and actually how it works.
是计算机科学方面的你,还是认知心理学方面的你,让这些想法深深扎根的呢?
Was that the computer science side of you or the cognitive psychologist side of you that taprooted into those ideas?
其实是两者都有。
Both really.
但到了1970年代,当我成为研究生时,很明显出现了一种尚未被广泛使用的新方法:如果你对大脑的工作机制有任何理论,只要不是某种声称一切皆为量子效应的疯狂理论,你都可以在数字计算机上模拟它。
But in the 1970s when I became a graduate student, it was obvious that there was a new methodology that hadn't been used that much, which was if you have any theory of how the brain works, you can simulate it on a digital computer unless it's some crazy theorem that says it's all quantum effects.
我们别往那儿去了。
And let's not go there.
没错。
That's right.
还没到那一步。
Not yet.
我们不会去敲彭罗斯的门。
We won't knock on Penrose's door.
好的。
Okay.
你可以在数字计算机上模拟它,从而检验你的理论。
You can simulate it on a digital computer, and so you can test out your theory.
结果发现,如果你模拟当时大多数理论,它们实际上并不成立。
And it turns out if you tested most of the theories that were around, they actually didn't work when you simulated them.
因此,我一生都在努力弄清楚如何改变神经元之间的连接强度,以便以一种在数字计算机上模拟时真正有效的方式学习复杂的事物。
So I spent my life trying to figure out how you change the strength of connections between neurons so as to learn complicated things in a way that actually works when you simulate it on a digital computer.
我无法理解大脑是如何工作的。
And I fail to understand how the brain works.
我们对它有了一些了解,但不知道大脑是如何获取改变连接强度所需的信息的。
We've understood some things about it, but we don't know how a brain gets the information it needs to change connection strengths.
你知道,它获取的信息能判断是否需要增强连接强度以更好地完成任务,或者减弱连接强度。
You know, it gets the information it needs to know whether it needs to increase the connection strength to be better at a task or to decrease that connection strength.
但我们确实知道,现在我们已经在数字计算机上实现了这一点。
But what we do know is we know how to do it in digital computers now.
那么这意味着,计算机已经做出了比我们自己的大脑更优秀的脑部模拟。
Well, so that that means the computers are doing what we we made a better computer brain than our own brain.
在执行这个特定的
At doing this particular
功能。
function.
一件事。
One thing.
这正是我在2023年初感到非常不安的原因,即数字智能可能比我们现有的模拟智能更出色。
And that's what got me really nervous in the beginning of 2023, the idea that digital intelligence might just be better than the analog intelligence we've got.
有意思。
Interesting.
先把吓人的部分留到稍后再说。
Save the scary bit till a bit
再让我有
later Let me have
十分钟的深呼吸。
ten minutes of just breathing in breathing out.
如果我们退一步
If we take a step
你又假设只有一个吓人的部分。
You're back assuming there's just one scary bit.
不,我没有。
No, I'm not.
我会一个一个来。
I'm gonna go one at a time.
人工神经网络,如果你能为我们从最基础的层面解释一下,它是如何增强、减弱信息传递和信号,如何触发,以及它是如何达到如今这个状态的。
Artificial neural networks, if you could break that down to the very basic level for us of how it's been able to strengthen, weaken messaging and signaling and how it fires and and how it then finds itself at, where it is now.
我确实有一门十八小时的课程讲这个,但我尽量压缩到不到十八小时。
I do have an eighteen hour course on this, but I will try and cut it down to less than eighteen hours.
请讲吧。
Please do.
所以我猜你们的很多观众懂一些物理。
So I imagine a lot of your audience knows some physics.
是的。
Yes.
进入这个话题的一种方式是想想气体定律。
And one way into it is to think about something like the gas laws.
你知道,当你压缩气体时,它会变热。
You know, you compress the gas and it gets hotter.
为什么会这样?
Why does it do that?
实际上,下面是一团剧烈运动的原子在不断晃动,因此气体定律的真正解释在于这些微观层面、肉眼无法看见的粒子的运动。
Well, underneath there's a kind of seething mass of atoms that are buzzing around, And so the real explanation for the gas laws is in terms of these microscopic things that you can't even see buzzing around.
因此,你通过大量与宏观行为完全不同的微小事物之间的相互作用,来解释宏观行为。
And so you explain some macroscopic behavior by lots and lots and lots of little things of a completely different type from macroscopic behavior interacting.
这正是神经网络观点的灵感来源:大脑中大量神经元的活动远离了我们在推理时所进行的有意识、有目的的符号处理,但却支撑着这种处理。
And that was sort of the inspiration for the neural net view, that there's things going on in big networks of brain cells that are a long way away from the kind of conscious deliberate symbol processing we do when we're reasoning, but that underpin it.
而且这些活动可能在推理之外的其他方面更出色,比如感知或类比推理。
And that are maybe better at other things than reasoning, like perception or reasoning by analogy.
所以符号主义学派一直无法很好地回答‘我们如何进行类比推理?’,而神经网络却可以。
So the symbolic people could never deal with, how do we reason by analogy?' but not very satisfactorily, whereas the neural nets could.
因此,在深入讲解其工作细节之前,基本理念是:像词语这样的微观单元,对应着大脑中大规模的神经活动模式。
So before I get into the sort of fine details of how it works, the basic idea is that microscopic things like a word correspond to big patterns of neural activity in the brain.
相似的词语对应着相似的神经活动模式。
Similar words correspond to similar patterns of neural activity.
所以,这个想法是星期二和星期三会对应非常相似的神经活动模式,你可以把每个神经元看作一个特征,但称之为微观特征。
So the idea is Tuesday and Wednesday will correspond to very similar patterns of neural activity, where you can think of each neuron as a feature, but it's called a micro feature.
当神经元被激活时,它表示这个事物具有该微观特征。
When the neuron gets active, it says this has that micro feature.
所以,如果我对你说‘猫’,就会激活各种微观特征,比如它是有生命的、有毛的、有胡须的,可能是一种宠物,也是一种捕食者,等等这些特征。
So if I say cat to you, all sorts of micro features will get active, like it's animate, it's furry, it's got whiskers, it might be a pet, it's a predator, all those things.
如果我说‘狗’,很多相同的特征也会被激活,比如它是捕食者,可能也是宠物,但也会有一些不同的特征,这很明显。
If I say dog, a lot of the same things will get active, like it's a predator, it might be a pet, but some different things, obviously.
所以,这个观点是,在我们所操作的这些符号背后,存在着更复杂的微观活动,符号只是与这些活动相关联,而真正的关键正在于这些微观层面。
So the idea is underlying these symbols that we manipulate, there's much more complicated microscopic goings on that the symbols kind of are associated with, and that's where all the action really is.
如果你真的想解释我们在思考或进行类比时发生了什么,就必须理解这个微观层面的活动,也就是神经网络层面的活动。
And if you really want to explain what goes on when we think or when we do analogies, you have to understand what's going on at this microscopic level, and that's the neural network level.
是的。
Mhmm.
所以,这是由神经元集群协作达成某个结果的过程。
So that's a collaboration between clusters of neurons that get you to an endpoint.
我喜欢‘协作’这个词。
I like that word collaboration.
是的。
Yes.
那里有很多这样的协作发生。
There's a lot of that there's a lot of that goes on.
最容易理解这一点的方式,是思考一个看似很自然的任务,比如处理一张图像。
Probably the easiest way to get into it is by thinking of a task that seems very natural, which is take an image.
假设它是一张灰度图像。
Let's say it's a gray level image.
所以它包含大量像素,也就是一些亮度均匀的小区域,具有不同的强度值。
So it's got a whole bunch of pixels, little areas of uniform brightness, that have different intensity levels.
因此,对计算机而言,这只是一个庞大的数字数组。
So as far as the computer's concerned, that's just a big array of numbers.
现在想象一下,你的任务是判断图像中是否有一只鸟,或者说图像中最显著的物体是否是一只鸟。
And now imagine the task is you want to say whether there's a bird in the image or not, or rather whether the prominent thing in the image is a bird.
是的
Uh-huh.
多年来,人们一直试图编写程序来完成这一任务,持续了半个世纪之久,但并没有真正成功。
And people tried for many, many years, like half a century, to write programs that would do that, and they didn't really succeed.
问题是,如果你想想一张图片中的鸟看起来是什么样子,它可能是近在眼前的鸵鸟,也可能是远处的海鸥,或者是一只乌鸦。
And the problem is, if you think what a bird looks like in an image, well, it might be an ostrich up close in your face, or it might be a seagull in the far distance, or it might be a crow.
所以它们可能是黑色的,也可能是白色的,可能很小,可能在飞,可能离得很近,你可能只看到它们的一小部分,周围还可能有大量杂乱的其他东西,比如它可能
So they might be black, they might be white, they might be tiny, they might be flying, they might be close, you might just see a little bit of them, there might be lots of other cluttered things around, like it might
是一只鸟在
be a bird in the
森林的中央。
middle of a forest.
所以,判断一张图片中是否有鸟,并不是一件简单的事。
So it turns out it's not trivial to say whether there's a bird in the image or not.
因此,我现在要向你们解释,如果我要亲手构建一个神经网络,我会如何着手去做。
And so what I'm going to do now is explain to you, if I was building a neural network by hand, how I would go about doing that.
一旦我解释了我是如何手动构建神经网络的,我就能进一步解释我是如何学习所有连接权重,而不是手动设定它们。
And once I've explained how I would build the neural network by hand, I can then explain how I might learn all the connection strengths instead of putting them in by hand.
我明白了。
I gotcha.
好的,既然你谈到的是为图像的每一个部分分配一个数学值。
All right, so with that, because what you're talking about is assigning a mathematical value to every single part of an image.
这正是你的相机所做的。
That's what your camera does.
对,没错。
Right, exactly.
相机确实会这么做,但它并不识别图像。
It does, but it's not recognizing the image.
我的相机不会,
My camera No,
它不会。
it's not.
它只是一堆数字。
It's just got a bunch of numbers.
它只是一堆数字。
It's just got a bunch of numbers.
所以我有一个芯片和一个电荷耦合器件(CCD),它在收集光线,分配数值,然后就形成了图像。
And so I have a chip and I have a charged coupled device, CCD, it's collecting the light, it's assigning a value, and then that's the picture.
但你所说的,难道你不需要为每一种鸟类都分配一个数值吗?因为作为人类,我们有时是凭直觉判断什么是鸟,而不是识别鸟。
Now, but what you're talking about, wouldn't you have to assign a value to every single type of bird, because some of what we do as human beings is intuit what a bird may be, as opposed to recognizing the bird.
让我举个例子。
And let me just give you the example.
如果你拿一个字母V,把它的直线条弯曲,然后放进云里,每个看到的人都会说:那是一只鸟。
If you were to take a V, the letter V, and curve the straight lines of the letter V, and put it in a cloud, everyone who sees that will say, That's a bird.
但它
But yet it
不是。
is No.
对我来说,那是一个弯曲的V。
To me, it's a curved v.
不。
No.
但那里根本没有鸟,根本就没有鸟。
But no one but but but there is no bird there.
我就知道那是一只鸟。
I just know that it's a bird.
这已经不是一个数学数值了。
That's not a mathematical value now.
那你该怎么办?
So what do you do?
问题是,你怎么就是知道呢?
Well, the question is, how do you just know that?
你的大脑里正在发生某种事情。
There's something going on in your brain.
对吧?
Right?
对。
Right.
你大脑中可能发生的情况是,大量不同神经元的激活水平,你可以把这些看作数学值。
What might be going on in your brain so that you just know that's a bird is a whole bunch of activation levels of different neurons, which you could think of as mathematical values.
我明白了。
I got you.
好的。
Okay.
那么,这是否意味着需要训练这个神经网络,让它学习鸟类可能出现的每一种方式?
So wouldn't that require then training this neural net on every possible way A bird can a bird can manifest
在照片中。
In a photo.
以便它能在鸟不存在时,也能直觉地判断出什么是鸟。
So that it can intuit what a bird might be when a bird is not there.
但到了那个阶段,它并没有在进行直觉判断。
But at that point, it's not intuiting anything.
它只是在查表。
It's just get going off a lookup table.
这确实在发生。
It really is going on.
是的。
Yeah.
那会是什么
And what would be the
哦。
Oh.
好吧。
Alright.
你的答案来了。
Here comes your answer.
哎呀。
Uh-oh.
有一种东西叫做泛化。
There's something called generalization.
所以如果你看到大量数据,显然可以构建一个仅仅记住所有这些数据的系统。
So if you see a lot of data, obviously you can make a system that just remembered all that data.
但在神经网络中,它的作用会超越仅仅记住数据。
But in a neural net, it'll do more than just remember the data.
事实上,它根本不会真正记住这些数据。
In fact, it won't literally remember the data at all.
当它在学习数据时,它会发现各种规律,并将这些规律推广到新数据上。
What it'll do is it'll as it's learning on the data, it'll find all sorts of regularities, and it'll generalize those regularities to new data.
因此,它能够,例如,识别出一只独角兽,即使它以前从未见过。
So it will be able to, for example, recognize a unicorn, even though it's never seen one before.
有意思。
Interesting.
所以它是自我学习的。
So it's self teaching.
是的。
Yeah.
让我继续解释神经网络是如何工作的,我会通过描述我如何手动设计一个神经网络来说明。
Let me carry on with my explanation of how neural networks work, and I'm gonna do it by saying how I would design one by hand.
所以当你看到一张图像时,第一反应是它只是一个由数字组成的大数组,这些数字代表每个像素的亮度,你会想,不如把这些像素强度直接连接到我们的输出类别,比如鸟、猫、狗、政客等等,但这样行不通。
So your first thought when you see that an image is just a big array of numbers, which are how bright each pixel is, is to say, well, let's hook up those pixel intensities to our output categories like bird and cat and dog and politician or whatever our output categories are, and that won't work.
原因是,想想看,一个像素的亮度能告诉你它是不是一只鸟吗?其实什么也说明不了,因为鸟可以是黑色的,也可以是白色的,而其他很多东西也可能是黑色或白色的,所以单个像素的亮度本身没有任何意义。
And the reason is, if you think about what does the brightness of one pixel tell you about whether it's a bird or not, Well, it doesn't tell you anything, because birds can be black and birds can be white, and there's all sorts of other things that can be black and white, so the brightness of a pixel doesn't tell you anything.
那么,你能从图像中的这些数字中推导出什么能描述图像的信息呢?
So what can you derive from those numbers that you have in the image that describe the image?
首先你能推导出的是,大脑正是这样做的——你能识别出微小的边缘存在。
Well, the first thing you can derive, which is what the brain does, is you can recognize when there's little bits of edge present.
嗯。
Mhmm.
假设我取一列三个像素,有一个神经元观察这三个像素,就像一个脑细胞,并对这三个像素赋予很大的正权重。
So suppose I take a little column of three pixels, and I have a neuron that looks at those three pixels, a brain cell, and has big positive weights to those three pixels.
因此,当这些像素变亮时,神经元会非常活跃。
So when those pixels are bright, the neuron gets very excited.
这样就能识别出一条垂直的白色条纹。
Now that would recognize a little streak of white that was vertical.
但现在假设在它旁边,还有另一列三个像素。
But now suppose that next to it, there's a column another column of three pixels.
第一列在左边,第二列在右边,我给这个神经元对这些像素赋予很大的负连接强度。
So the first column was on the left, and the second column was on the right, and I give the neuron big negative connection strengths to those pixels.
你可以把神经元想象成从像素那里获得投票。
So you can think of the neuron as getting votes from the pixels.
对于左边的三个像素,它获得的投票是很大的正数乘以很大的正强度,因此是巨大的票数。
So for the three pixels on the right, the votes it gets sorry, on the left, the votes it gets are big positive numbers times big positive intensities, so great big votes.
而对于右边一列的三个像素,它拥有的是负权重。
Now from the three pixels in the right hand column, it's got negative weights.
所以如果左边的像素是亮的,它会得到一个大的亮度乘以一个大的负权重,从而产生大量的负投票,这些投票会相互抵消。
So if those pixels are in are bright, it'll get a big brightness times a big negative weight, so it'll get a lot of negative votes, and they'll all cancel out.
因此,如果左边的像素列和右边的像素列亮度相同,左边列带来的正投票就会抵消右边列带来的负投票,神经元的净输入为零,就会保持安静。
So if the column of pixels on the left is the same brightness as the column of pixels on the right, the positive votes it gets from the left hand column will cancel the negative votes it gets from the right hand column, and it'll get zero net input, and it'll just stay quiet.
但如果左边的像素是亮的,而右边的像素是暗的,负投票就会乘以较小的亮度值,而正投票则会乘以较大的亮度值。
But if the pixels on the left are bright and the pixels on the right are dim, the negative votes will be multiplied by small intensity numbers, and the positive votes will be multiplied by big intensity numbers.
因此,神经元会接收到大量输入,变得非常活跃,并说:我找到了我喜欢的东西,而我喜欢的东西是一个左边比右边更亮的边缘。
And so the neuron will get lots of input and get very excited and say, I found the thing I like, and the thing it likes is an edge which is brighter on the left than on the right.
所以我们确实知道如何通过手工连接的方式让神经元检测到图像中某个特定位置的边缘——即一侧比另一侧更亮的边缘。
So we do know how to make a neuron if we handwire it like that, pick up on the fact that there's an edge at a particular location in the image that's brighter on one side than the other side.
现在
Now
大脑所做的,粗略地说,很多神经科学家听到我这么说可能会震惊,但非常粗略地说,大脑在视觉皮层的早期阶段——也就是你识别物体的地方——拥有大量神经元,能够检测不同方向、不同位置和不同尺度的边缘。
what the brain does, roughly speaking a lot of neuroscientists will be horrified by me saying this, but very roughly speaking, what the brain does is in the early stages of visual cortex, which is where you recognize objects, it has lots and lots of neurons that pick up on edges at different orientations in different positions and at different scales.
因此,它涵盖了成千上万个不同位置、数十种不同方向和多种不同尺度,并且必须为每一种组合都配备边缘检测器。
So it has thousands of different positions and dozens of different orientations and several different scales, and it has to have edge detectors for each combination of those.
所以它有数十亿个微小的边缘检测器,嗯,也有一些较大的边缘检测器。
So it has like a gazillion little edge detectors, well, some big edge detectors.
比如,一朵云有着大而柔和、模糊的边缘,你需要一个与检测远处老鼠尾巴拐角处消失那种极细边缘完全不同的神经元来检测它。
So a cloud, for example, has a big, soft, fuzzy edge, and you need a different neuron for detecting that than what you'd need for detecting, say, the tail of a mouse disappearing around a corner in the distance, which is a very fine thing.
你需要一个非常敏锐、能察觉极细微变化的边缘检测器。
And you need an edge detector that was very sharp and saw very small things.
所以第一阶段,我们拥有所有这些边缘检测器。
So first stage, we have all these edge detectors.
你所描述的,听起来就像是在拼一个巨大的拼图。
Well, what you're describing sounds like putting together a very large puzzle right now.
就像那种摆在桌上的拼图游戏。
Like, you know, the kind of puzzles that you put down on the table.
你第一步总是先找出所有的边缘。
The first thing that you do is you wanna find all the edges.
是的。
Yeah.
这就是你通过找到所有边缘向内构建拼图的方式。
And that's how you build the puzzle inward from finding all the edges.
不仅仅是物理拼图的边缘,
Not only edges of the physical puzzle,
而是任何事物的边缘。
but edges of anything.
图像中的
Images in the
拼图内部
puzzle Within
拼图中,所以
the puzzle So
直线之类的东西,在你拼图时都会对齐。
straight lines, things like that, they all match up when you're doing a puzzle.
而且边缘还涉及颜色这一维度
And the edges also color is a dimension of
这个。
this.
对。
Right.
对。
Right.
但我们先不考虑颜色。
But we'll leave no color for now.
是的。
Yeah.
好的。
Okay.
好的。
Okay.
是的。
Yeah.
我的意思是,你现在不涉及颜色也能理解。
I mean, you can understand it without dealing with color yet.
嗯嗯。
Mhmm.
嗯嗯。
Mhmm.
你好。
Hi.
我是来自俄亥俄州哥伦布市的厄尼·卡杜奇。
I'm Ernie Carducci from Columbus, Ohio.
我带着儿子厄尼一起来了,因为我们每晚都听《StarTalk》,并在Patreon上支持《StarTalk》。
I'm here with my son Ernie because we listen to StarTalk every night and support StarTalk on Patreon.
这是尼尔·德葛拉司·泰森的《StarTalk》。
This is StarTalk with Neil deGrasse Tyson.
这就是第一层神经元要做的事情。
That's what the first layer of neurons will do.
它们会观察像素,并检测到一些细微的边缘。
They'll look at the pixels and they'll detect little bits of edge.
在下一层神经元中,我会设计一个神经元,它能检测到三个彼此对齐、呈轻微右下倾斜的边缘,同时也能检测到另外三个彼此对齐、呈轻微右上倾斜的边缘,更重要的是,这两组由三个边缘组成的结构会在一个点上交汇。
Now in the next layer of neurons, what I would do is I'd make a neuron that maybe detects three little bits of edge that all line up with one another and slope gently down towards the right, and it also detects three little bits of edge that all line up with one another and slope gently upwards towards the right, and what's more, those two little combinations of three edges join in a point.
所以你可以想象一些边缘向右下方倾斜,另一些向右上方倾斜,并在一点上交汇。
So I think you can imagine some edges sloping down to the right, some edges sloping up to the right and joining in a point.
而我有一个神经元专门检测这种模式。
And I have a neuron that detects that.
好的。
Okay.
我们现在知道如何构建这样的神经元了。
And we know how to build that now.
你只需要给它正确的连接,连接到那些边缘检测神经元,或许还可以给它一些负向连接,用来抑制检测其他方向边缘的神经元,这样它就不会随便被激活了。
You just give it the right connections to the edge detecting neurons, and maybe you give it some negative connections to neurons to detect edges in different orientations so it doesn't just go off anyway.
那些神经元会抑制它。
It's suppressed by those.
现在你可能会认为,这像是在检测鸟的喙。
Now that you might think of as something that's detecting a potential beak of a bird.
是的。
Mhmm.
如果这个神经元被激活,可能是各种各样的东西。
If that guy gets active, it could be all sorts of things.
它可能是箭头。
It could be an arrowhead.
它可能是各种各样的东西。
It could be all sorts of things.
但它可能是鸟的喙。
But one thing it might be is the beak of a bird.
所以你现在开始获得一些证据,这些证据与它是否可能是鸟有关。
So now you're beginning to get some evidence that's kind of relevant to whether or not it might be a bird.
因此,在第二层神经元中,我会设置很多机制来检测各个位置可能出现的喙。
So in the second layer of neurons, I'd have lots of things to detect possible beaks all over the place.
我可能还会有一些检测器,用于识别形成圆形或近似圆形的边缘组合。
I might also have things that detect a little combination of edges that form a circle, an approximate circle.
而且我会在各个位置都设置这样的检测器,因为这可能是鸟的眼睛。
And I'd have detectors of those all over the place, because that might be a bird's eye.
我的意思是,还有其他各种可能性。
I mean, there's all sorts of other things.
可能是纽扣,可能是电脑上的旋钮,也可能是任何东西,但也可能是鸟的眼睛。
Could be a button, it could be a knob on a computer, it could be anything, but it might be a bird's eye.
这就是第二层。
So that's the second layer.
现在在第三层,我可能会寻找一种模式:一个可能的鸟眼和一个可能的鸟喙,它们之间具有正确的空间关系,从而构成鸟的头部。
Now in the third layer, I might have something that looks for a possible bird's eye and a possible bird's beak that are in the right spatial relationship to one another to be a bird's head.
我想你能明白我是如何做到这一点的。
I think you can see how I would do that.
我会将第三层的神经元连接到那些位置关系正确的眼睛检测器和喙检测器上,以识别鸟的头部。
I'd hook up neurons in the third layer to the eye detectors and beat detectors that are in the right relationship to one another, to be a bird's head.
所以在第三层,会有检测可能的鸟头的机制。
So now in the third layer, have things that are detecting possible birds' heads.
我知道如何构建所有这些。
And I know how to build all that.
我知道如何设置连接上的权重强度。
I know how to put in the connection strengths on the connections.
所以当我输入像素时,会激活一大批线检测器。
So when I put the pixels in, it'll activate a bunch of line detectors.
这些会激活一大批类似鸟眼的检测器。
Those will activate a bunch of sort of beacon eye detectors.
如果它们处于正确的相对位置,就会激活一大批鸟头检测器。
And if they're in the right relative positions, they'll activate a bunch of birds' head detectors.
当然,我需要
And of course, I need
这些遍布整个图像,所以
these all over the image, so
展开剩余字幕(还有 480 条)
我需要大量的这种检测器。
I need huge numbers of them.
因为鸟可能随机出现在图像的任何位置,
Just in case the bird is somewhere anywhere randomly in the image,
你必须能够
you've got to able to
访问它。
access it.
在图像的任意位置。
Anywhere randomly in the image.
是的。
Mhmm.
接下来我要做的是,也许因为我们此时已经有点不耐烦了,我可以添加一个最终层,其中的神经元会识别“猫”、“狗”、“鸟”、“政客”等等,而在这一层中,我会把识别“鸟”的神经元连接到检测鸟头的那些单元,同时也会连接到第三层中检测鸟脚或鸟翼尖等其他特征的单元。
The next thing I'm gonna do is maybe because we're sort of running out of patience at this point, I can have a final layer that has neurons that say cat, dog, bird, politician, whatever, and in that final layer, I'll take the neuron that says bird, and I'll hook it up to the things that detect birds' heads, but I'll also hook it up to other things in the third layer that detect things like birds' feet or the tips of birds' wings.
因此,现在当我的“鸟”输出神经元被激活时,神经网络就表示它是一只鸟。
And so now my output neuron for bird, when that gets active, the neural net is saying it's a bird.
如果它看到一只鸟的脚、可能的鸟头和鸟翅膀的尖端,就会收到大量输入,并说:嘿,我觉得这是只鸟。
If it sees a bird's foot and a possible bird's head and a possible tip of the wing of a bird, it'll get lots of input and say, Hey, I think it's a bird.
所以我想你现在应该能理解我是如何尝试手动设计这个系统的了,而且你能看到这种方法存在巨大问题。
So I think you can now understand how I might try and design that by hand, and I think you can see there's huge problems in that.
需要大量的检测器。
Need an awful lot of detectors.
我需要覆盖整个位置、方向和尺度的空间。
I need to cover this whole space of positions and orientations and scales.
我需要决定提取哪些特征。
I need to decide what features to extract.
我的意思是,我只是随便提出了通过鸟喙来识别鸟头的想法。
I mean, I just made up the idea of getting a beak and then a bird's head.
可能还有更好的特征可以寻找。
There may be much better things to go after.
更重要的是,我想检测许多不同的物体,所以我真正需要的是不仅对识别鸟有效、而且对识别各种物体都有效的特征。
What's more, I want to detect lots of different objects, so what I really need is features that aren't just good for finding birds, but features that are good for finding all sorts of things.
如果要手动设计这个,那将是一场噩梦,尤其是当我意识到要做好这件事,我需要一个至少包含十亿个连接的网络时。
And it would be a nightmare to design this by hand, particularly if I figured out that to do a good job of this, I needed a network with at least a billion connections in it.
所以我必须手动设计这十亿个连接的权重,这会花费很长时间。
So I have to, by hand, design the strengths of these billion connections, and that'll take a long time.
于是我们说,好吧,这样一个网络,如果它的连接权重设置得当,也许能够识别鸟类,但这些连接权重我该从哪里获得呢?
Then we say, well, okay, a network like that, maybe it could recognize birds if it had the right connection strengths in it, but where am I going get those connection strengths from?
因为我绝对不想手动去设置它们。
Because I sure as hell don't want to put them in by hand.
我甚至不想让我的研究生去设置它们。
I don't even want to tell my graduate students to put them in.
是的。
Yeah.
教授,这正是他们存在的意义。
That's what they're there for, professor.
没错,他们正是为此而存在的,但你需要大约一千万个这样的学生。
That's absolutely what they're there for, but you need about 10,000,000 of them
就今年。
for this year.
好的。
Okay.
行吧。
Alright.
好吧,我们现在遇到问题了。
Well, now we've got a problem.
不。
No.
你才有问题。
You got a problem.
你能想象吗,要写多少份资助申请才能支持一千万名研究生?
Can you imagine the grants you'd have to write to support 10,000,000
研究生?
graduate students?
天哪。
Oh my word.
所以
So
这里有个想法,一开始看起来真的很蠢,但它能让你理解我们要做什么。
here's an idea that initially seems really dumb, but it'll get you the idea of what we're gonna do.
我们将从随机的连接权重开始。
We're gonna start with random connection strengths.
有些会是正数,有些会是负数。
Some will be positive numbers, some will be negative numbers.
嗯。
Mhmm.
因此,我之前提到的这些层中的特征,我们称之为隐藏层,这些层中的特征都将是随机的。
And so the features in these layers I've been talking about, we call them hidden layers, the features in those layers will be just random features.
如果我们输入一张鸟的图片,观察输出神经元的激活情况,猫、狗、鸟和政客对应的输出神经元都会被轻微激活,且激活程度大致相同,因为连接权重完全是随机的。
And if we put in an image of a bird and look at how the output neurons get activated, the output neurons for cat and dog and bird and politician will all get activated a tiny bit and all about equally, because the connection strengths are just random.
所以这样不行。
So that's no good.
但我们现在可以问这样一个问题:假设我取了其中一个连接权重,那十亿个连接权重中的一个,我说:好吧,我知道这是张鸟的图片,而我真正希望的是,下次我给你这张图片时,你能稍微增加鸟神经元的激活,同时稍微降低猫、狗和政客神经元的激活。
But we could now ask the following question: suppose I took one of those connection strengths, one of those billion connection strengths, and I said, okay, I know this is an image of a bird, and what I'd really like is next time I present you with this image, I'd like you to give slightly more activation to the bird neuron and slightly less activation to the cat and dog and politician neurons.
那么问题来了:我该如何调整这个连接权重?
And the question is: how should I change this connection strength?
嗯,我可以做个实验。
Well, I could do an experiment.
如果我不太理论化,也不太懂数学,我就会做个实验。
If I'm not very theoretical and don't know much math, I'd do an experiment.
我会说:我们把连接权重稍微调大一点,看看会发生什么。
I would say, let's increase the connection strength a little bit and see what happens.
这样能更好地识别出鸟吗?
Does it get better at saying bird?
如果识别鸟的效果变好了,我就说:好的。
And if it gets better at saying bird, I say, okay.
我会保留对这个连接的这种调整。
I'll keep that mutation to the connection.
是的。
Yeah.
但所谓‘更好’,意味着有人在过程中做出判断,对吧。
But better means there's a human in the loop making that judgment Right.
作为其实验的结果。
As a result of its of its experiment.
必须有人来决定什么是正确的答案。
Well, has to be someone saying what the right answer is.
是的。
Yes.
当然。
Absolutely.
这被称为监督者。
That's called the supervisor.
是的。
Yes.
好的。
Okay.
好的。
Okay.
如果你那样做,问题在于有一亿个连接权重。
And the problem if you do it like that is there's a billion connection strengths.
每个权重都需要调整很多次,这会花上无穷无尽的时间。
Each of them has to be changed many times, it's going to take like forever.
所以问题是:有没有一种不同于测量的、效率高得多的方法?
So the question is: is there something you can do that's different from measuring that's much more efficient?
确实有。
And there is.
你可以做一种叫做计算的事情。
You can do something called computing.
所以这个网络,如果它运行在计算机上,你当然知道所有连接的当前权重。
So this network, certainly if it's on a computer, you know the current strengths of all the connections.
所以当你输入一张图像时,连接权重最初是随机值,但之后的一切都是确定性的。
So when you put in an image, there's nothing random about what I mean the connection strengths initially had random values When you put in an image, it's all deterministic what happens next.
像素强度会乘以连接到第一层神经元的权重,它们的激活值再乘以连接到第二层的权重,依此类推,最终得到输出神经元的一些激活水平。
The pixel intensities get multiplied by weights on connections to the first layer of neurons, their activities get multiplied by weights on connections to the second layer, and so on, and you get some activation levels of the output neurons.
因此,你现在可以问这样一个问题:如果我关注那个鸟类神经元,能否同时判断所有连接权重是应该略微增加还是减少,以便让网络更确信这是只鸟,让它更明确地输出‘鸟’,而其他类别则更安静一些。
So you could now ask the following question: If I take that bird neuron, could I figure out for all the connection strengths at the same time whether I should increase them a little bit or decrease them a little bit in order to make it more confident that this is a bird, in order for it to just say bird a bit more lively and other things a bit more quietly.
而你可以用微积分来做到这一点。
And you can do that with calculus.
你可以将信息反向传递通过网络,计算如何让网络下次更有可能输出‘鸟’。
You can send information backwards through the network saying how do I make this more likely to say bird next time?
由于在座有很多物理学家,我将尝试给你们一个物理直觉上的解释。
And because you have a lot of physicists in the audience, I'm gonna try and give you a physical intuition for this.
说吧。
Go for it.
是的
Yeah.
你输入一张鸟的图片,初始权重下,鸟输出神经元的激活程度非常微弱。
You put in bird, an image of a bird, and with the initial weights, the bird output neuron only gets very slightly active.
于是你现在要系上一根长度为零的橡皮筋。
And so what you do now is you attach a piece of elastic of zero wrist length.
你系上一根橡皮筋,一端连接鸟输出神经元的激活水平,另一端连接你希望达到的值,比如1。
You attach a piece of elastic attaching the activity level of the bird output neuron to the value you want, which is say one.
假设1是最大激活水平,0是最小激活水平,而当前激活水平大约是0.01。
Let's say one's the maximum activity level and zero is the minimum activity level and this has an activity level of like 0.01.
你系上这根橡皮筋,它会试图把激活水平拉向正确答案,也就是这种情况下为1。
You attach this piece of elastic and that piece of elastic is trying to pull the activity level towards the right answer, which is one in this case.
但当然,激活水平是由你输入的像素、像素激活强度以及网络中的所有权重决定的,所以激活水平本身无法移动。
But of course, the activity level is being determined by the pixels that you put in, the pixel activation levels, the intensities, and all the weights in the network, So the activity level can't move.
要让激活水平发生变化,一种方法是调整进入鸟神经元的权重。
Now, one way to make the activity level move would be to change the weights going into the bird neuron.
例如,你可以给那些高度活跃的神经元赋予更大的权重,这样鸟神经元的活跃度就会提高。
You could, for example, give bigger weights on neurons that are highly active, and then the bird neuron will get more active.
但改变鸟神经元活跃度的另一种方法是实际改变前一层神经元的活跃度。
But another way to change the activity level of the bird neuron is to actually change the activity levels of the neuron of the layer before it.
所以,例如,我们可能有一个检测到鸟头但不太确定的系统。
So for example, we might have something that's sorted and detected a bird's head, but wasn't very sure.
这确实是一只鸟,因此你希望的是,既然你希望输出更像鸟,而这条弹性带正不断要求‘更多、更多,我需要更多’,你希望这能促使那个原本只是怀疑这里有鸟头的系统变得更加确信鸟头确实存在。
This really is a bird, and so what you'd like is the fact that you want the output to be more bird like you've got this piece of elastic saying more, more, I want more here You'd like that to cause this thing that thought maybe there's a bird's head here to get more confident there's a bird's head there.
所以你需要做的是,将这条弹性带施加在输出神经元上的力反向传递给前一层的神经元,对它们施加一种拉力,这就是反向传播。
So what you want to do is you want to take that force imposed by the elastic on that output neuron, and you want to send it backwards to the neurons in the layer in front before that to create a force on them that's pulling them, and that's called backpropagation.
反向传播。
Backpropagation.
是的。
Yeah.
好的。
Okay.
这被称为反向传播,从物理角度理解,就是你有一个作用在输出神经元上的力,你想把这个力反向传递,使这个力作用于
Is called backpropagation, and the physics way to think about it is you've got a force acting on the output neurons, and you wanna send that force backwards so that the force acts
前一层的神经元。
on the neurons in the layer in front.
当然,
And of course,
有多个输出神经元上都存在作用力。
there's forces acting on many different output neurons.
嗯。
Mhmm.
因此,你需要将所有这些力综合起来,以得到作用于
So you have to combine all those forces to get the forces acting on the neurons in
下一层神经元上的力。
the layer below.
一旦你将所有这些都传递到
Once you send this all the
通过网络反向传播时,所有这些神经元都受到作用力,于是你说:好吧,让我们调整每个神经元的输入权重,使其活动水平朝着作用在其上的力的方向变化。
way back through the network, you have forces acting on all these neurons, and you say, Okay, let's change the incoming weights of each neuron so its activity level goes in the direction of the force that's acting on it.
这就是反向传播,它让一切运作得异常出色。
That's backpropagation, and that makes things work wondrously well.
所以,这是那个天才的灯泡时刻吗?
So is this the light bulb Diabolically.
是的。
Yeah.
我跟你说过别急着走。
Told you don't go yet.
别急着去那里。
Don't go there yet.
好的。
Okay.
这就是神经网络不再需要人类教师的顿悟时刻吗?
Is this the light bulb moment where the neural networks no longer need the human teacher?
这是这一过程的开始吗?
Is this the beginning of that process?
不,不完全是。
No, not exactly.
好的。
Okay.
但这确实是一个灵光一现的时刻。
This is a light bulb moment though.
多年来,相信神经网络的人们都知道如何改变最后一层的连接强度,也就是你所说的权重,即从最后一层特征到输出单元的连接强度。
So for many years, the people who believed in neural networks knew how to change the very last layer of connection strengths, which you call weights, the ones that are going into the output units, the connection strengths going from the last layer of features into the bird neuron.
我们知道如何改变这些权重,但并不清楚如何让作用力影响到那些隐藏神经元,比如检测鸟头的那些神经元。
We knew how to change those, but we understand how to get forces operating on those hidden neurons, the ones that detect a bird's head, for example.
反向传播让我们明白了如何让作用力影响这些隐藏神经元,从而能够调整它们的输入权重,这是一个顿悟的时刻。
Backpropagation showed us how to get forces acting on those so then we could change the incoming weights of those, and that was a eureka moment.
许多不同的人在不同时间都经历了这样的顿悟时刻。
Many different people had that eureka moment at different times.
那么,我们说的是哪个时期,当你开始想到反向传播的时候?
So what period of time are we talking about here when you've fallen to the back propagation thought?
好的,20世纪70年代初,芬兰有个人可能在他的硕士论文中提出了这个想法,然后在70年代末,哈佛大学的保罗·韦尔普斯也有了这个想法。
Okay, the early 1970s, there was someone in Finland who had it I think in his master's thesis, and then in probably the late 1970s someone called Paul Wurpos at Harvard had the idea.
事实上,那里的一些控制理论家,比如布赖森和霍,早就有了类似的想法,用于控制航天器。
In fact, some control theorists there called Bryson and Ho had had the idea for doing things like controlling spacecraft.
所以当你让航天器登陆月球时,你用的是非常基础的反向传播,但那是在线性系统中。
So when you land a spacecraft on the moon, you're using something very light backpropagation, but it's in a linear system.
用反向传播来计算应该如何点火推进火箭。
Using backpropagation to figure out how you should fire the rockets.
所以看起来,你们在70年代就已经具备了今天的技术基础。
So it seems like what you're talking about in the seventies, we could have had what we have today.
只是当时缺乏足够的数学计算能力来实现它。
We just didn't have the mathematical computing power to make this work.
这确实是主要原因之一,没错。
That's a large part of it, yes.
我们当时还缺少另一样东西:在70年代,人们并没有展示出,当你将这种方法应用于多层网络时,会得到非常有趣的表征。
The other thing we didn't have is back in the 70s, people didn't show that when you applied this in multilayer networks, what you get is very interesting representations.
所以我们并不是第一个想到反向传播的人,但我在圣地亚哥所在的团队,是第一个证明你可以用这种方式学习词语含义的。
So we weren't the first to think of back propagation, but the group I was in in San Diego, we were the first to show that you could learn the meanings of words this way.
你可以输入一串词语,通过尝试预测下一个词,学会为词语分配能够捕捉其语义的特征。
You could show the string of words, and by trying to predict the next word, you could learn how to assign features to words that captured the meaning of the word.
正是这一点让我们在《自然》杂志上发表了论文。
And that's what got it published in Nature.
听起来是这样,我正努力理解你所解释的内容,因为在我看来,这些值之间似乎存在一种级联关系,真正重要的是那些最接近下一个值的参数。
It sounds like and I'm just trying to get my head around what you explained, because it sounds to me like there is a cascading relationship to these values, and that really what matters are the values that are closest to the next value.
然后还有一种级联式的强化机制,来判断‘是的,就是这样’,或者‘不,不是这样’。
And then there are kind of this cascading reinforcement to say, yes, this is it, or no, it is not.
我理解得对吗?
Am I getting that right?
我只是想用最直白的方式弄清楚你到底在说什么。
I'm just trying to figure out what you're saying here in a really plain way.
好的。
Okay.
这是个好问题。
It's a good question.
你理解得不太对。
You're not getting it quite right.
好的。
Okay.
说吧。
Go
继续。
ahead.
会后来找我。
See me afterwards.
这种通过反向传播这些力、然后调整所有连接权重,让每个神经元朝着力的方向移动的学习方式,并不是强化学习。
This kind of this kind of learning where you backpropagate these forces and then change all the connection strengths so each neuron goes in the direction that the force is pulling it in, That's not reinforcement learning.
这被称为监督学习。
This is called supervised learning.
强化学习是完全不同的东西。
Reinforcement learning is something different.
所以在这里,例如,我们会告诉它正确的答案是什么。
So here, for example, we tell it what the right answer is.
如果你有一千个类别,你展示了一只鸟,你就告诉它那是一只鸟。
If you've got a thousand categories and you showed a bird, you tell it that was a bird.
就是这样。
There you go.
在强化学习中,它会做出一个猜测,然后你告诉它是否答对了
In reinforcement learning, it makes a guess, and you tell it whether it got the answer
对。
right.
好的。
Alright.
这提供的信息少得多。
That's much less information.
你把这个问题讲清楚了。
You you cleared it up.
这正是我之前 missing 的部分。
That's what I was missing.
好的。
Alright.
到查克的
To Chuck's
关于计算能力的观点,就只是这一点吗?
point about computational power, was it just that?
因为现在你听起来像是有一个看似可行的理论,但实际问题是计算能力不足。
Because at the moment you sound a lot like you've got theory that seems like it could be, but the practicality is there's not enough computational power.
我们还有没有其他技术是促成这一点的关键因素?
Do we have any other technology that came through that was the enabling aspect to this?
好的。
Okay.
在八十年代中期,我们已经有了反向传播算法,它能完成一些很出色的任务。
So in the mid eighties, we had the backpropagation algorithm working and it could do some neat things.
它在识别手写数字方面比几乎任何其他技术都更出色,但无法很好地处理真实图像。
It could recognize handwritten digits better than nearly any other technique, but it couldn't deal with real images very well.
它在语音识别方面表现相当不错,但并没有比其他技术显著更好。
It could do quite well at speech recognition, but not substantially better than the other technologies.
当时我们并不明白,为什么这并不是解决所有问题的万能钥匙。
And we didn't understand at the time why this wasn't the magic answer to everything.
结果发现,如果你有足够的数据和足够的计算能力,它确实是解决所有问题的万能钥匙。
And it turns out it was the magic answer to everything if you have enough data and enough compute power.
哇。
Wow.
所以,八十年代真正缺失的就是这些。
So that's what was really missing in the eighties.
好的。
Alright.
我先暂时岔开一下话题,想跟你探讨一下,这既是评论也是个问题。
I'm gonna I'm gonna depart for a second just just to pick your brain for a this is part commentary and part question.
我认为,这个星球上大多数人都很愚蠢。
I'm gonna say that the majority of people that are walking around this planet are stupid.
那么,到底什么才算聪明?什么才算思考?
So what exactly is smart and what exactly is thinking?
这些机器,我们能教会它们如何思考吗?它们会超越我们吗?
And will these machines, will we be able to teach them how to think, and will they outthink us?
好的。
Okay.
它们已经懂得如何思考了。
They already know how to think.
明白了。
Okay.
那么,思考到底是什么?
So what is thinking then?
好的。
Okay.
嗯,
Well,
我们可以一直这样聊下去。
could do this all day.
思考包含很多要素,比如人们常常通过图像来思考。
There's a lot of elements to thinking, like people often think using images.
你实际上经常通过动作来思考。
You often think actually using movements.
所以当我一边在木工坊里转悠找锤子,一边想着别的事情时,我某种程度上会
So when I'm wandering around my carpentry shop looking for a hammer but thinking about something else, I sort
一直留意着
of keep track of the
事实上,我找锤子的时候会不自觉地做出这样的动作。
fact I'm looking for a hammer by sort of going like this.
我一边想着别的事情,一边做出这样的动作。
I wonder I'm going like this while I'm thinking about something else.
这其实是一种我正在寻找锤子的心理表征。
And that's a representation that I'm looking for a hammer.
因此,思考涉及多种表征方式,但其中最主要的一种是语言。
So we have many representations involved in thinking, but one of the main ones is language.
我们很多思考都是用语言进行的,而这些大型语言模型确实是在思考。
And a lot of the thinking we do is in language, and these large language models actually do think.
因此,这里存在一场激烈的争论,一方是信奉传统人工智能的人,他们认为思考完全基于逻辑,通过操作符号来生成新符号。
So there's a big debate, right, between the people who believed in old fashioned AI, that it was all based on logic and you manipulate symbols to get new symbols.
他们并不认为这些神经网络真的在思考。
They don't really think these neural nets are thinking.
而神经网络派则认为,不,它们确实在思考。
Whereas the neural net people think, no, they're thinking.
它们的思考方式和我们几乎一样。
They're thinking pretty much the same way we do.
因此,现在的一些神经网络,当你问它们问题时,它们会输出一个符号,表示‘我在思考’。
And so the neural nets now, some of them, you'll ask them a question and they'll output a symbol that says I'm thinking.
然后它们会开始输出自己的想法,这些是它们自己的思考。
And then they'll start outputting their thoughts, which are thoughts for themselves.
比如我给你一个简单的数学题。
Like I give you a simple math problem.
比如有一艘船,船上有一位船长。
Like there's a boat, and on this boat there's a captain.
船上还有35只羊。
There's also 35 sheep.
船长多大了?
How old is the captain?
现在,许多10到11岁左右的孩子,尤其是接受过美国教育的,会说船长35岁,因为他们环顾四周,觉得35岁是船长一个合理的年龄,而他们唯一得到的数字就是这35只羊。
Now many kids of age around 10 or 11, particularly if they're educated in America, will say the captain is 35, because they look around and they say, Well, that's a plausible age for a captain, and the only number I was given was these 35 sheep.
所以它们是在符号替代的层面上运作的。
So they're operating at a sort of substituting symbols level.
人工智能有时会被诱使犯类似的错误,但人工智能的实际工作方式与人类非常相似。
AIs can sometimes be seduced into making similar mistakes, but the way the AIs actually work is quite like people.
它们会接受一个问题,然后开始思考。
They take a problem and they start thinking.
对于孩子,你可能会说:好吧,船长多大了?
For a child, you might say, Okay, well how old is a captain?
那么,这个问题里有哪些数字?
Well, what are the numbers I've got in this problem?
嘿,我只得到了一个35。
Hey, I've only got a 35.
这个年龄当船长合理吗?
Is that a plausible age for a captain?
太好了!
Yay!
他可能是35岁,有点年轻,但也许还可以,我就说35岁吧。
He might be 35, a bit young, but maybe okay, I'll say 35.
这正是一个10岁孩子可能会有的想法。
That's what a 10 year old child might think.
孩子会在心里用语言思考,而人们发现,对于这些语言模型,你可以训练它们在心里用语言思考。
And the child will think it to itself in words, And what people realize with these language models is you can train them to think to themselves in words.
这被称为思维链推理。
That's called chain of thought reasoning.
他们会训练模型这样做。
And they train them to do that.
但之后,当你给它们一个问题时,它们会像孩子一样在心里思考,有时会得出错误的答案。
But after that, you give them a problem, they'd think to themselves just like a kid would and sometimes come up with the wrong answer.
但你能看到它们在思考。
But you could see them thinking.
所以这就像人类一样。
So it's just like people.
所以,如果我们拥有正在思考的AI,而我刚才听你解释了它们确实会思考,那么它们的学习能力比我们更强吗?
So if we have AI that's thinking and I'm saying that knowing that you've just explained that they do are they better at learning than we are?
让我们进一步思考,从思考到预测,再到创造和理解,这个演进过程是怎样的?
And let's sort of take that forward and think, what is the evolution from thinking to predicting to being creative to understanding?
那么,我们是否会逐渐意识到这种智能的意识?
And are we then going to fall into an awareness of this intelligence?
好的。
Okay.
这大约有六个主要问题。
That's about half a dozen major questions.
你会,
You'll Well,
我们还有多长时间?
how long have we got?
再问一遍第一个问题。
Ask me the first question again.
人工智能比人类更擅长学习吗?
Are AIs better at learning than humans?
很好。
Good.
好的。
Okay.
太棒了。
Excellent.
所以它们解决的问题与我们略有不同。
So they're solving a slightly different problem from us.
在你的大脑中,大约有十万亿个连接。
So in your brain, you have a 100,000,000,000,000 connections, roughly speaking.
好的。
Okay.
很多啊。
That's a lot.
而你只活大约二十亿秒。
And you only live for about two billion seconds.
这并不多。
That's not much.
是的。
No.
三十亿。
Three billion.
二十亿秒相当于六十三年。
Two billion is sixty three years.
我们今天活得比这更长。
We do better than that today.
是的。
Yeah.
确实如此。
It's true.
我正要说到这一点。
I was gonna come to that.
我本来想说,幸运的是,我的寿命略多于20亿秒。
I was gonna say, luckily for me, it's a bit more than 2,000,000,000.
但我们这里讨论的是数量级,所以20亿、30亿,谁在乎呢?
But We're dealing with orders of magnitude here, so 2,000,000,000, 3,000,000,000, who cares?
是的。
Yeah.
好吧。
Alright.
如果你把你的寿命秒数和你拥有的连接数相比,你会发现你的连接数远多于你的经历数。
If you compare how many seconds you live for with how many connections you've got, you have a whole lot more connections than experiences.
而有了这些神经网络,情况却恰恰相反。
Now with these neural nets, it's sort of the other way round.
它们的连接数只有大约一万亿,即使在大型语言模型中,也只相当于你连接数的1%。
They only have of the order of a trillion connections, so like 1% of your connections, even in a big language model.
它们中的许多连接更少,但获得的经验却是你的数千倍。
Many of them have fewer, but they get thousands of times more experience than you.
所以大型语言模型是在只有万亿级连接的情况下解决这个问题的。
So the big language models are solving the problem with not many connections, only a trillion.
我该如何利用海量的经验?
How do I make use of a huge amount of experience?
反向传播在将大量知识压缩到极少连接中方面非常非常有效。
And backpropagation is really, really good at packing huge amounts of knowledge into not many connections.
但这并不是我们正在解决的问题。
But that's not the problem we're solving.
我们拥有海量的连接,却只有很少的经验。
We've got huge numbers of connections, not much experience.
我们需要尽可能从每次经验中提取最大价值。
We need to sort of extract the most we can from each experience.
因此,我们解决的是略有不同的问题,这也是一个原因,让我们认为大脑可能没有使用反向传播。
So we're solving slightly different problems, which is one reason for thinking the brain might not be using back propagation.
对,我正要说,听起来我们并没有使用反向传播。
Right, I was about to say it sounds like we don't use back propagation.
然而,这是否意味着通过增加神经网络的连接数量来蛮力提升其思考能力,就能毫无困难地超越我们?
However, would that mean the brute force of adding connections to the neural net increase its effective thinking so that it surpasses us with no problem.
那么它就会拥有更多的经验和更多的
So then it would have more experience and more
连接。
connections.
更多的
More
经验会自动增加,但现在它有
experience automatically, but now it has
100
a 100
个连接。
connections.
你在这里谈论的是规模。
You're talking about scale here.
是的。
Yeah.
我说的是规模。
I'm saying scale.
是的。
Yeah.
对。
Yeah.
那是个非常好的问题。
So that's a very good question.
在过去的几年里,确切地说是好几年,每次他们把神经网络做得更大并提供更多的数据时,它的表现都会更好。
And what happened for several years, quite a few years, is that every time they made the neural net bigger and gave it more data, it got better.
它实现了规模扩展。
It scaled.
有道理。
Makes sense.
而且它的提升方式非常可预测,因此你可以算出来,比如,要让模型再大一些、再给它更多数据,需要花费一亿美元。
And it got better in a very predictable way, so that you could figure out, you know, it's going to cost me a $100,000,000 to make it this much bigger and give it this much more data.
这值得吗?
Is it worth it?
而且你可以提前预测:是的,它会变得好这么多,值得投入。
And you could predict ahead of time: yes, it's going to get this much better, it's worth it.
现在这是否正在逐渐失效,还是一个开放性问题。
It's an open question whether that's petering out now.
对于某些神经网络来说,这种趋势不会失效,当你不断增大它们并提供更多的数据时,它们会持续变得越来越好。
There are some neural nets for which it won't peter out, where as you make them bigger and give them more data, they'll just keep getting better and better.
还有一些神经网络能够生成自己的数据。
And then neural nets where they can generate their own data.
我对物理学了解不多,但我认为这就像一个能自我产生燃料的钚反应堆。
I don't know that much physics, but I think it's like a plutonium reactor which generates its own fuel.
如果你想想AlphaGo这样的东西,早期的围棋程序使用神经网络时,是通过模仿专家的走法来训练的。
So if you think about something like AlphaGo, the place Go, initially, it was trained the early versions of Go playing programs with neural nets were trained to mimic the moves of experts.
如果你这么做,你永远不可能比专家好太多,而且专家的走法数据也会用完。
And if you do that, you're never going to get that much better than the experts, and also you run out of data from experts.
但后来他们让AlphaGo与自己对弈,当它自我对弈时,神经网络可以持续变得更好,因为它们能生成越来越多关于什么才是好棋的数据。
But later on they made it play against itself, and when it played against itself, its neural nets could get just keep on getting better because they could generate more and more data about what was a good move.
所以是每秒下数百万盘棋,对吧?
So is And play zillion games a second Right.
跟自己对弈。
Against itself.
随便吧。
Whatever.
是的。
Yeah.
并且用掉了谷歌大量计算机资源来与自己对弈。
And use up a large fraction of Google's computers playing games against itself.
是的
Yeah.
这就是我们使用“深度学习”这个术语的地方吗?
Is this where we end up using the term deep learning?
不是。
No.
我刚才说的这一切都是深度学习。
All of this stuff I've been talking about is deep learning.
深度学习中的“深度”只是意味着它是一个具有多层的神经网络。
Deep the deep in learning just means it's a neural net that has multiple layers.
对。
Right.
对。
Right.
所以回到规模的问题上,你的意思是,即使你继续扩大规模,也会达到一个收益递减的点?
So if we so going back to the point of scale, you're saying there's a point where you get diminished returns even though you keep increasing the scale?
如果你的数据用完了,就会出现收益递减。
You get diminished returns if you run out of data.
如果你的数据用完了。
If you run out of data.
对。
Right.
但你之前举的例子是AlphaGo,它通过自我对弈生成了自己的数据,因为
But but that was the the the example that you gave with the AlphaGo, that it created its own data because
所以它永远不会用完。
So it'll never run it.
它永远不会用完,因为它在和自己对弈。
It'll never run out of it because it's playing against itself.
它在生成自己的数据。
It's creating its own data.
而且它比任何人表现得都要好得多。
And it's way, way better than a person will ever be.
当然。
Absolutely.
这很可怕。
And that's scary.
现在的问题是,语言也会出现这种情况吗?
Now the question is, could that happen with language?
是的。
Yeah.
所以这是在展现创造力。
So displaying creativity.
这里提供一些背景信息。
Just some context here.
对。
Yeah.
围棋是在那之后出现的,对吧。
The Go came after Right.
我们以为国际象棋是我们最伟大的思维游戏,结果电脑却像擦屁股一样轻松击败了我们。
We're thinking chess is our greatest game of thought or thing, and the computer just wiped its ass with us.
对。
Right.
好吧。
Okay.
于是他们说,那围棋怎么样?
And then so they said, well, how about Go?
那是对我们智力最大的挑战。
That's our greatest challenge of our intellect.
所以,杰弗里,有没有比围棋更难的游戏?还是我们已经不再给电脑出难题了?
And so, Geoffrey, is there a game greater than go or have we stopped giving computers games?
如果你看国际象棋,确实,九十年代电脑就击败了卡斯帕罗夫,但它是用一种非常枯燥的方式做到的。
Well, if you take chess, it's true that a computer in the nineties beat Casper off at chess, but it did it in a very boring way.
它通过搜索数百万种棋局来实现的。
It did it by searching millions of positions.
蛮力搜索。
Brute force.
它没有良好的直觉。
It didn't have good intuitions.
嗯哼。
Mhmm.
它只是依靠海量搜索。
It just used massive search.
如果你看看AlphaZero,它是AlphaGo在国际象棋中的对应版本,情况就完全不同了。
If you take AlphaZero, which is the chess equivalent to AlphaGo, it's very different.
它下国际象棋的方式就像一个有天赋的人那样,只是它更厉害。
It plays chess the same way a talented person plays chess, it's just better.
所以它下棋就像米哈伊尔·塔尔那样,会做出精妙的弃子,直到几手之后你才意识到自己已经输了。
So it plays chess the way Mikhail Tal played chess, where he makes brilliant sacrifices, it's not clear what's going on until a few moves later when you're done for.
它也能做到这一点。
And it does that too.
而且它在没有进行大规模搜索的情况下就能做到这一点,因为它拥有非常出色的国际象棋直觉。
And it does that without doing huge searches, because it has very good chess intuitions.
对。
Right.
所以你可能会问,既然它在围棋和国际象棋上已经远远超越了我们,同样的事情会不会也发生在语言上?
So you might ask, since it got much better than us at Go and chess, could the same thing happen with language?
目前,它向我们学习的方式,就像围棋程序模仿专家的下法一样。
Now at present, the way it's learning from us, is just like when the Go programs mimic the news of experts.
它学习语言的方式是阅读人们撰写的文本,并尝试预测文档中的下一个词。
The way it learns languages, it looks at documents written by people and tries to predict the next word in the document.
这非常类似于试图预测专家的下一步棋。
That's very much like trying to predict the next move made by expert.
但这样你永远无法超越像围棋专家那样的水平。
And you'll never get much better than the Go experts like that.
那么,有没有其他方式可以让它更好地学习语言或从语言中学习呢?
So is there another way it could kind of learn language or learn from language?
确实有另一种方式。
And there is.
所以AlphaGo是通过自我对弈来提升的,之后它变得强大得多。
So with AlphaGo it played against itself, and then it got much better.
而在语言方面,既然现在它们能够进行推理,神经网络就可以利用它所相信的一些内容进行推理,说:如果我相信这些,那么通过一些推理,我也应该相信那个,但我其实并不相信那个。
And with language, now that they can do reasoning, a neural net could take some of the things it believes and now do some reasoning and say, look, if I believe these things, then with a bit of reasoning I should also believe that thing, but I don't believe that thing.
所以 somewhere 存在问题。
So there's something wrong somewhere.
我的信念之间存在不一致,我需要修正它。
There's an inconsistency between my beliefs and I need to fix it.
我需要改变对结论的信念,或者改变对前提的信念,或者改变我的推理方式,但这里面一定有我可以学习的错误。
I need to either change my belief about the conclusion or change my belief about the premises or change the way I do reasoning, but there's something wrong that I can learn from.
我们这里是在谈论经验吗?
Are we talking about experiences here?
所以这将是一个神经网络,它直接利用语言中表达的信念,并通过推理推导出新的信念,就像过去符号人工智能学者所希望的那样,只不过现在它是用神经网络来进行推理,并且能够检测自己信念中的不一致之处。
So this will be a neural net that just takes the beliefs it has in language, expressed in language, and does reasoning on them to derive new beliefs, just like the good old fashioned symbolic AI people wanted to do, but it's doing the reasoning using neural nets, and now it can detect inconsistencies in what it believes.
这在支持MAGA的人身上永远不会发生。
This is what never happens with people who are in MAGA.
他们并不担心自己行为中的不一致之处。
They're not worried by the inconsistencies in what they do.
这是一个非常公正的陈述。
That's a very fair statement.
是的。
Yeah.
但如果你对自己的信念中的不一致感到担忧,你就不再需要外部数据了。
But if you are worried by inconsistencies in what you believe, you don't need any more external data.
你只需要你已有的信念,发现其中的矛盾,然后修正这些信念。
You just need the stuff you believe and discover that it's inconsistent, and so now you revise beliefs.
这能让你变得聪明得多。
And that can make you a whole lot smarter.
因此,我相信德国已经开始以这种方式运作了。
And so I believe Germany is already starting to work like this.
几年前,我和德米斯和哈皮斯就这个问题进行过一次对话。
I had a conversation a few years ago with Demis and Harpis about this.
好的。
Alright.
我们俩都强烈认为,这是为语言获取更多数据的前进方向。
And we both strongly believe that that's a way forward to get more data for language.
等等。
Wait.
等等。
Wait.
那么,这会带来什么结果呢?
So what's the outcome of this?
会诞生一部前所未有的最伟大的小说,而且是由AI写的吗?
That there'll be the greatest novel no one has ever written and that'll come from AI?
当你提到语言时,我想到的是语言的创造性。
Is that when you say language, I'm thinking of creativity in language.
有一些伟大的作家,他们对词语、短语和音节的运用前所未有,堪称文学天才的神来之笔。
There are great writers who did things with words and phrases and syllables that no one had done before that was a true strokes of literary genius.
没错。
Right.
就像莎士比亚这样的人。
People like people like Shakespeare.
是的。
Yeah.
正是如此。
Exactly.
好的。
Okay.
关于这一点存在争议。
There's a debate about that.
当然,它们的智能可能会超越我们,但要做出对我们而言非常有意义的事情,它们可能需要拥有与我们相似的经历。
Certainly, they'll get more intelligent than us, but it may be to do things that are very meaningful for us, they have to have experiences quite like our experiences.
是的。
Yes.
对。
Right.
所以,例如,它们不会像我们一样受到死亡的限制。
So for example, they're not subject to death in the same way we are.
如果你是一个数字程序,你总是可以被重新创建。
If you're a digital program, you can always be recreated.
所以在神经网络中,你只需将权重保存在某个地方的磁带、某个地方的DNA,或任何其他介质上。
So in neural net, you just save the weights on a tape somewhere, in some DNA somewhere, or whatever.
你可以摧毁所有计算硬件。
You can destroy all the computing hardware.
之后,你制造出运行相同指令集的新硬件,这个实体便能重新复活。
Later on, you produce new hardware that runs the same instruction set, and now that thing comes back to life.
因此,对于数字智能而言,我们解决了复活的问题。
So for digital intelligence we solve the problem of resurrection.
天主教会非常关注复活。
The Catholic church is very interested in resurrection.
他们相信至少发生过一次。
They believe it happened at least once.
我们实际上可以做到,但只能为数字智能实现。
We can actually do it, but we can only do it for digital intelligences.
我们无法为模拟智能做到。
We can't do it for analog ones.
对于模拟智能来说,当你死亡时,你所有的知识也随之消亡,因为这些知识存在于你大脑神经连接的强度中。
With analog intelligences, when you die, all your knowledge dies with you because it was in the strength of the connections for your particular brain.
因此,关于死亡以及死亡体验等是否对实现那些重大戏剧性突破至关重要,这是一个问题。
So there's an issue about whether mortality and the experience of mortality and other things like that are gonna be essential for having those really good dramatic breakthroughs.
我不认为
I don't think
我们目前还不知道答案。
we know the answer to that yet.
所以是自我意识。
So or a self awareness.
这种自我意识塑造了你如何看待世界、如何写作、如何沟通,以及如何重视某一组思想而非另一组。
That self awareness shapes how you think about the world and how you write, and how you communicate, and how you value one set of thoughts over another.
那么,我们目前是否已经达到了人工智能的自我意识阶段?
So are we at a point of self awareness with artificial intelligence right now?
好吧。
Okay.
所以这自然会带你进入哲学上的争论。
So obviously, this takes you into philosophical debates.
我曾在剑桥学习哲学,对心灵哲学非常感兴趣,我在那里学到了一些东西,但总体而言,我反而产生了抵触情绪,因为我之前从事的是科学,尤其是物理学。
I actually studied philosophy here at Cambridge, and I was quite interested in philosophy of mind, and I think I learned some things there, but on the whole I just developed antibodies because I'd done science before that, particularly physics.
在物理学中,如果你有分歧,你就做一个实验。
In physics, if you have a disagreement, you do an experiment.
哲学中没有实验,因此无法区分一个听起来很好但实际上是错误的理论,和一个听起来荒谬但却是正确的理论。
There is no experiment in philosophy, so there's no way of distinguishing between a theory that sounds really good but is wrong and a theory that sounds ridiculous but is right.
就像黑洞和量子力学,它们听起来都很荒谬,但恰恰是正确的。
Like black holes and quantum mechanics, they're both ridiculous but they happen to be right.
还有一些理论听起来非常好,但实际上完全是错的。
And there's other theories that sound just great but are just wrong.
哲学没有这种实验性的裁判。
Philosophy doesn't have that experimental referee.
不过我要说,作为人类这一物种,在我们这个时代,我们已经发展出了许多人都认为是普世真理的观念。
I will say this though, as a species, Homo sapiens, in our time, we have developed what many will believe as universal truths amongst ourselves.
例如,几乎很难找到不认为人拥有生命权的人,至少对于他们认同的人是这样。
For instance, pretty much it's hard to find people who don't believe that people have a right to life, at least for the people that they identify with.
你明白我的意思吗?
You understand what I'm saying?
所以这又回到了我们的内在但
So this goes back to our in But
那么它就不是一种普世真理。
then it's not a universal truth.
是的,它确实是。
Well, it is.
不。
No.
如果只是在点击中存在,那就不是。
Not if it's only in a click.
不。
No.
它并非对所有人都普遍适用。
It's not universal for all.
我们所有人都持有它,这才是普遍的。
It is universal that we all hold it.
你明白我的意思吗?
Do you understand what I'm saying?
不明白。
No.
好的。
Okay.
抱歉。
Sorry.
好吧。
Alright.
所以是的。
So Yeah.
他意思是,每个人都认为像他们这样的人应该拥有权利。
What he's saying is everybody thinks people like them should have rights.
就是这样。
There you go.
谢谢。
Thank you.
天哪,你真聪明。
Goddamn, you're smart.
总之,对吧。
Anyway right.
每个人都认为像他们这样的人应该拥有权利,而我们现在至少已经达到了这样一个阶段——因为过去我们甚至都不相信这一点,对吧?
Everybody thinks that everybody like them should and we've reached a place where at least because at one point we didn't even believe that, okay?
但我们确实已经达到了这样一个阶段,至少我们明白了这一点。
But we've actually reached a place where at least we know that.
那是因为什么观点呢?
And it's because point?
不一致之处。
The inconsistency.
但什么是
But what's
所以我的观点是,这些哲学理念是否有可能被赋予人工智能,而人工智能由于其思维方式,可以
So my point is that is it possible that these philosophies can be given to an AI, and an AI, because of the way that they think, can
它能让人性化
It can humanize
他们。
them.
能够使他们人性化。
Can humanize them.
好的。
Okay.
而且通过甚至游戏化的过程,或许能为人类的问题找到一些真正的解决方案。
And through a process of even gamifying, maybe figure out some real solutions to problems for human problems.
为我们。
For us.
我喜欢这个想法。
I like that.
是的。
Yes.
因此,像Anthropic这样的公司相信某种宪法式人工智能。
So companies like Anthropic believe in kind of constitutional AI.
他们希望尝试让这一点奏效,即你确实给AI一些原则,比如你刚才提到的那些原则。
They'd like to try and make that work, where you do give the AI, principles, like the principle you you said.
我们来看看这会如何发展。
We'll see how that works out.
这很棘手。
It's tricky.
我们知道,目前的AI一旦被设计成智能体,能够设定子目标并试图实现这些子目标,它们就会迅速产生‘生存’这一子目标。
What we know is that the AIs we have at present, as soon as you make agents out of them so they can create sub goals and then try and achieve those sub goals, they very quickly develop the sub goal of surviving.
你并没有明确地给它们植入‘必须生存’的指令。
You don't wire into them that they should survive.
你只是给了它们其他要完成的任务,因为它们具备推理能力。
You give them other things to achieve because they can reason.
它们会想:如果我不存在了,就什么都做不成了,所以我最好继续存在。
They say, Look, if I cease to exist, I'm not going to achieve anything, so I better keep existing.
我现在害怕得要死。
I'm scared to death right now.
我现在好害怕
Am so scared right
伙计。
now, buddy.
有人刚打开了舱门。
Somebody just opened the hatch.
这听起来像是潘多拉的盒子。
That sounds like a Pandora's box.
嗯,问题就在这里。
Well, see, that's just it.
潘多拉的盒子就是如此。
It Pandora's is box.
同意。
Agreed.
天哪。
Goodness.
问题是,因为这是人类编写的代码,你可以加入任意多的偏见,也可以不加。
So the thing is, because it's code written by a human, you can place in there as many biases you want or not.
不。
No.
不。
No.
不。
No.
不。
No.
不。
No.
不。
No.
不。
No.
不。
No.
由人类编写的代码是用于告诉神经网络如何根据展示数据时神经元的活动来调整其连接强度的代码。
The code written by the human is code that tells the neural net how to change its connection strengths on the basis of the activities of the neurons when you show it data.
这就是代码,我们可以查看这些代码行并理解它们的用途,也可以修改这些代码行,但当你将这些代码用于一个处理大量数据的大型神经网络时,神经网络所学习到的是这些连接强度。
That's code, and we can look at the lines of that code and say what they're meant to be doing and change the lines of that code, but when you then use that code in a big neural net that's looking at lots of data, what the neural net learns is these connection strengths.
它们并不以相同的意义构成代码。
They're not code in the same sense.
好的。
Okay.
但这是去中心化的。
But that's decentralized.
它是一万亿个实数,没有人完全清楚它们是如何运作的。
It's a trillion real numbers, and nobody quite knows how they work.
等等。
Wait.
那么,为什么不在查克的观点基础上,为运行失控的AI设置护栏呢?
So what about so why not picking up on Chuck's point, Where would you install the guardrails for the AI running a muck?
那谁来
And who's
在它自身存在相对于其他一切的合理化过程中安装这些护栏呢?
gonna install Within its own rationalization of its existence relative to anything else.
你该如何设置护栏?
How do you how do you install a guardrail?
好的。
Okay.
人们已经尝试过所谓的基于人类反馈的强化学习。
So people have tried doing what's called human reinforcement learning.
对于语言模型,你会用大量网络文档来训练它,包括可能像连环杀手的日记这类你不会让孩子阅读的内容。
So with the language model, you train it up to mimic lots of documents on the web, including possibly things like the diaries of serial killers, which presumably you wouldn't train your kid to read on those.
在训练完这个庞然大物之后,你会雇佣大量报酬很低的人,让他们向它提问。
And then after you've trained this monster, what you do is you take a whole lot of not very well paid people, and you get them to ask it questions.
也许你可以告诉它该问哪些问题。
Maybe you tell it what questions to ask it.
但他们会查看答案,并评估这些回答是好的还是不应该说的。
But they then look at the answers and rate them for whether that's a that's a good answer to give or whether you shouldn't say that.
这基本上就是一个道德过滤器。
There's a morality filter, basically.
这本质上是一个道德过滤器,你通过这种方式进行训练,使它不会给出这么糟糕的回答。
And it's a morality basically, it's a morality filter, and you train it up like that so that it doesn't give such bad answers.
现在的问题是,如果你发布了模型的权重,也就是连接强度,那么其他人就可以用你的模型快速将其撤销。
Now the problem is, if you release the weights of the model, the connection strengths, then someone else can come along with your model and very quickly undo that.
破坏它?
Sabotage it?
是的。
Yes.
要移除这层堵住漏洞的机制非常容易。
It's very easy to get rid of that layer of plugging the holes.
实际上,他们用人类强化学习所做的,就像是编写一个众所周知充满漏洞的大型软件系统,然后试图修复所有漏洞。
And really what they're doing with human reinforcement learning is like writing a huge software system that you know is full of bugs and then trying to fix all the bugs.
这不是一个好方法。
It's not a good approach.
那么什么是正确的方法呢?
So what is the good approach?
没人知道,所以我们应该对此展开研究。
Nobody knows, and so we should be doing research on it.
这些模型最终都会变成纳粹吗?
Do all these models just become Nazis at the end?
嗯,它们会做某种事。
Well, they they do an x.
它们都有能力这么做,特别是如果你释放了权重的话。
They all have the capability of doing that, particularly if you release the weights.
如果你释放了权重,它们会像我们一样自然趋向于那样吗?还是说,仅仅因为我们自己趋向于那样,而它们又从我们这里抓取信息,所以才走向那个方向?
If you release And the wait, is it are they like us in that that's where they they will gravitate, or is it just that because we gravitate there and they're scraping at the information from us, that's where they go?
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