Why consciousness?

我要和各位談談意識，

Well, it's a curiously neglected subject,

為什麼是意識呢？

both in our scientific and our philosophical culture.

嗯，說也奇怪，這是一個被忽略的學科，

Now why is that curious?

不管是在科學還是在哲學領域中，

Well, it is the most important aspect of our lives

為什麼這麼奇怪？

for a very simple, logical reason,

嗯，意識對生命有重要的意義，

namely, it's a necessary condition on anything

原因簡單又合理，

being important in our lives that we're conscious.

也就是說，在生命中的所有重要事情上，

You care about science, philosophy, music, art, whatever --

擁有意識是必要的狀態。

it's no good if you're a zombie or in a coma, right?

你關心科學、哲學、音樂、美術等，

So consciousness is number one.

但是如果你是殭屍或植物人， 就不太好了吧？

The second reason is that when people do

因此意識是最重要的。

get interested in it, as I think they should,

第二個原因是，

they tend to say the most appalling things.

當人們對它感興趣時， 如同我說的，他們應該要有興趣，

And then, even when they're not saying appalling things

他們傾向說最可怕的事。

and they're really trying to do serious research,

然後，即使他們不說可怕的事，

well, it's been slow. Progress has been slow.

他們還真的會試著認真做研究，

When I first got interested in this, I thought, well,

嗯，有點慢，進展得有點慢。

it's a straightforward problem in biology.

我剛開始對這個議題感興趣時，

Let's get these brain stabbers to get busy and figure out

我想，嗯，這是一條關於生物學的簡單問題。

how it works in the brain.

我們可以拿些開腦的椎子，來看看

So I went over to UCSF and I talked to all

意識怎麼在腦袋裡運作。

the heavy-duty neurobiologists there,

因此，我去了加州大學舊金山分校 (UCSF)，

and they showed some impatience,

和那裡所有重量級的神經生物學家討論，

as scientists often do when you ask them embarrassing questions.

他們顯得有點不耐煩，

But the thing that struck me is, one guy said in exasperation,

就像當你問科學家 讓他難堪的問題時的模樣。

a very famous neurobiologist, he said, "Look,

但是讓我驚訝的是， 有一位老兄腦羞成怒地說，

in my discipline it's okay to be interested in consciousness,

他是很有名的神經生物學家，他說：

but get tenure first. Get tenure first."

「你聽好，在我這一行你可以對意識有興趣，

Now I've been working on this for a long time.

但你要先取得終身教授職位才行。 先取得終身教授職！」

I think now you might actually get tenure

我做這個研究很久了，

by working on consciousness.

我想藉由做點意識研究，

If so, that's a real step forward.

也許你也可以成為終身教授了，

Okay, now why then is this curious reluctance

如果這樣的話，那還真是前進了一大步。

and curious hostility to consciousness?

好吧，那為什麼意識總會奇怪地

Well, I think it's a combination of two features

不被重視或反對？

of our intellectual culture

嗯，我認為這是

that like to think they're opposing each other

人類智力文化的兩大特點，

but in fact they share a common set of assumptions.

那就是愛說自己和對方持相反看法，

One feature is the tradition of religious dualism:

但是事實上，他們有同樣的假設。

Consciousness is not a part of the physical world.

第一個特點是宗教二元論的傳統思維：

It's a part of the spiritual world.

意識不屬於物質世界，

It belongs to the soul,

意識是精神世界的一部分。

and the soul is not a part of the physical world.

它屬於靈魂，

That's the tradition of God, the soul and immortality.

而靈魂不是物質世界的一部分。

There's another tradition that thinks it's opposed to this

這是上帝、靈魂和不滅的傳統思維。

but accepts the worst assumption.

另外有一項傳統思維和這個觀點完全相反，

That tradition thinks that we are heavy-duty scientific materialists:

而且選擇了最差的假設。

Consciousness is not a part of the physical world.

那個傳統思維認為我們都是 背負著重大責任的科學唯物主義者：

Either it doesn't exist at all, or it's something else,

意識並不是物質世界的一部分。

a computer program or some damn fool thing,

它要嘛根本就不存在， 不然就是別種東西，

but in any case it's not part of science.

一個電腦程式或是某種該死的蠢東西，

And I used to get in an argument that really gave me a stomachache.

但絕不會是科學的一部分。

Here's how it went.

我常會爭論到胃很痛。

Science is objective, consciousness is subjective,

結果是這樣。

therefore there cannot be a science of consciousness.

科學是客觀的，而意識是主觀的。

Okay, so these twin traditions are paralyzing us.

因此不可能有一種叫意識的科學。

It's very hard to get out of these twin traditions.

好吧，這兩個雙胞傳統思維讓我們動彈不得。

And I have only one real message in this lecture,

很難跳脫這兩個傳統雙胞胎。

and that is, consciousness is a biological phenomenon

這堂課我只有一句真正的訊息要傳達，

like photosynthesis, digestion, mitosis --

那就是，意識是一種生命現象，

you know all the biological phenomena -- and once you accept that,

就像光合作用、消化作用、細胞有絲分裂，

most, though not all, of the hard problems

你知道所有的生命現象，一旦你接受了，

about consciousness simply evaporate.

大部分，雖然不是全部，

And I'm going to go through some of them.

關於意識的難題就會消失無蹤了。

Okay, now I promised you to tell you some

接下來我會再多做解釋。

of the outrageous things said about consciousness.

我之前承諾要告訴你一些

One: Consciousness does not exist.

跟意識有關的荒謬論點。

It's an illusion, like sunsets.

第一：意識是不存在的。

Science has shown sunsets and rainbows are illusions.

那是錯覺，就像夕陽，

So consciousness is an illusion.

科學證明夕陽和彩虹都是錯覺，

Two: Well, maybe it exists, but it's really something else.

如此看來意識也是一種錯覺。

It's a computer program running in the brain.

第二：好吧，也許它存在， 但那真的是別的東西，

Three: No, the only thing that exists is really behavior.

那是在腦袋裡運轉的電腦程式。

It's embarrassing how influential behaviorism was,

第三：不對，行為動作才是真正唯一存在的東西。

but I'll get back to that.

行為主義的影響力如此深遠，真讓人尷尬，

And four: Maybe consciousness exists,

我們稍後再討論。

but it can't make any difference to the world.

第四：也許意識存在，

How could spirituality move anything?

但是它不能為世界帶來任何改變。

Now, whenever somebody tells me that, I think,

精神怎麼可能移動得了東西？

you want to see spirituality move something?

現在只要有人這樣問我，我會想，

Watch. I decide consciously to raise my arm,

你想看我用精神移動東西嗎？

and the damn thing goes up. (Laughter)

你看好。我決定有意識地要舉起我的手臂，

Furthermore, notice this:

然後這該死的東西就舉起來了。 (笑聲）

We do not say, "Well, it's a bit like the weather in Geneva.

還有，給我仔細聽好，

Some days it goes up and some days it doesn't go up."

我們不會說：「嗯，這有點像日內瓦的天氣，

No. It goes up whenever I damn well want it to.

有時候它會舉起來，有時候不會。」

Okay. I'm going to tell you how that's possible.

不會！只要我想讓它舉起來， 它就會舉起來！

Now, I haven't yet given you a definition.

那麼，讓我來跟你說這是怎麼辦到的。

You can't do this if you don't give a definition.

我還沒給你一個定義，

People always say consciousness is very hard to define.

如果沒有下定義的話，無法跟你解釋。

I think it's rather easy to define

人們總是說意識很難定義，

if you're not trying to give a scientific definition.

我倒覺得容易，

We're not ready for a scientific definition,

只要你不去試著用科學的角度來定義它。

but here's a common-sense definition.

我們還沒準備好要用科學來定義，

Consciousness consists of all those states of feeling

但是我們可以用常識來定義。

or sentience or awareness.

意識包含了所有感覺、

It begins in the morning when you wake up from a dreamless sleep,

知覺或覺察的狀態。

and it goes on all day until you fall asleep

當你一夜好眠後醒來，

or die or otherwise become unconscious.

它一早就會開始出現，直到你再度熟睡，

Dreams are a form of consciousness on this definition.

或是死亡，或是失去知覺。

Now, that's the common-sense definition. That's our target.

在這個定義中，夢是意識的一種形式。

If you're not talking about that, you're not talking about consciousness.

這就是常識性的定義，這是我們的目標。

But they think, "Well, if that's it, that's an awful problem.

如果你不談論那件事，你就不能談論意識。

How can such a thing exist as part of the real world?"

但是他們會想：「好啊， 如果是這樣，那還真是個大麻煩，

And this, if you've ever had a philosophy course,

怎麼可能存在著這種事， 成為真實世界中的一部份？」

this is known as the famous mind-body problem.

如果你曾上過哲學課，

I think that has a simple solution too. I'm going to give it to you.

這就是有名的心物問題 (mind-body problem)。

And here it is: All of our conscious states, without exception,

我認為這也有一個簡單的解決辦法， 我馬上告訴你。

are caused by lower-level neurobiological processes in the brain,

那就是我們所有的意識狀態，沒有例外，

and they are realized in the brain

都是由腦中較低層次的神經生物的過程所引起的，

as higher-level or system features.

意識以較高層次或是系統特徵

It's about as mysterious as the liquidity of water.

在大腦中被理解。

Right? The liquidity is not an extra juice squirted out

這就像是水的流動性那樣神奇，

by the H2O molecules.

對吧？流動不是由水分子噴出

It's a condition that the system is in.

多餘的果汁，

And just as the jar full of water can go from liquid to solid

那是一種系統在其中的狀態。

depending on the behavior of the molecules,

就像是滿罐子的水，可以從液體變成固體，

so your brain can go from a state of being conscious

視水分子的行為而變化，

to a state of being unconscious,

所以你的大腦也可以從有意識的狀態，

depending on the behavior of the molecules.

轉變為無意識的狀態，

The famous mind-body problem is that simple.

全看分子的行為來變化。

All right? But now we get into some harder questions.

有名的心物問題就是那麼簡單。

Let's specify the exact features of consciousness,

那麼，我們要探討更困難的問題了，

so that we can then answer those four objections

我們來詳細說明意識的特徵，

that I made to it.

這樣一來，我們就可以回答我剛才提出的

Well, the first feature is, it's real and irreducible.

那四個反對的聲音。

You can't get rid of it.

嗯，第一個特徵是，它是真實且不能減少的。

You see, the distinction between reality and illusion

你不能丟掉它。

is the distinction between how things

你看，現實和錯覺之間的差別，

consciously seem to us and how they really are.

就如同在意識上，事情對我們來說是什麼樣子，

It consciously seems like there's --

和它實際的樣子之間的差別。

I like the French "arc-en-ciel" —

意識上，就像是有

it seems like there's an arch in the sky,

──我喜歡法文中的「arc-en-ciel」──

or it seems like the sun is setting over the mountains.

就像是有一道彩虹在天空中，

It consciously seems to us, but that's not really happening.

或是太陽掛在山頂上。

But for that distinction between

在意識中是如此，但是在現實中卻不然。

how things consciously seem and how they really are,

但是在意識上看起來的樣子，

you can't make that distinction for the very existence of consciousness,

與事實上的樣子之間的差別，

because where the very existence of consciousness is concerned,

你無法那樣區別意識的存在，

if it consciously seems to you that you are conscious,

因為意識的存在在於關注，

you are conscious.

如果在意識上對你來說，你是有意識的，

I mean, if a bunch of experts come to me and say,

那你就是有意識。

"We are heavy-duty neurobiologists and we've done a study

我的意思是，如果一大票專家來跟我說：

of you, Searle, and we're convinced you are not conscious,

「我們是重量級的神經生物學家，

you are a very cleverly constructed robot,"

我們對你，希爾勒，做了研究， 我們相信你沒有意識，

I don't think, "Well, maybe these guys are right, you know?"

你是一個被設計得很聰明的機器人。」

I don't think that for a moment, because, I mean,

我不會想：「嗯，也許這些人是對的，是吧？」

Descartes may have made a lot of mistakes, but he was right about this.

我一刻也不會懷疑，

You cannot doubt the existence of your own consciousness.

因為笛卡兒也許犯了很多錯， 但是有件事他說對了，

Okay, that's the first feature of consciousness.

你不能懷疑自己的意識存在。

It's real and irreducible.

這是意識的第一項特徵。

You cannot get rid of it by showing that it's an illusion

它是真實且不能減少的。

in a way that you can with other standard illusions.

你不能用其它標準的錯覺來比照，

Okay, the second feature is this one

說它是錯覺而就此認定它不存在。

that has been such a source of trouble to us,

第二個特徵

and that is, all of our conscious states

是我們困擾已久的根源，

have this qualitative character to them.

那就是我們所有的意識狀態

There's something that it feels like to drink beer

對它們來說都有這個實質的樣貌。

which is not what it feels like to do your income tax

那就像是喝啤酒，

or listen to music, and this qualitative feel

跟你在算所得稅或聽音樂的感覺不同，

automatically generates a third feature,

這個實質的感覺

namely, conscious states are by definition subjective

自然而然地產生了第三項特徵，

in the sense that they only exist as experienced

也就是意識狀態

by some human or animal subject,

是主觀的定義，

some self that experiences them.

只會存在於某個人、動物的經驗，

Maybe we'll be able to build a conscious machine.

某些有經驗過意識的自我。

Since we don't know how our brains do it,

也許我們將來能夠製造一台有意識機器。

we're not in a position, so far, to build a conscious machine.

由於我們不知道大腦如何讓意識運作，

Okay. Another feature of consciousness

到目前為止，我們就還不能製造有意識的機器。

is that it comes in unified conscious fields.

接下來，另一個意識的特徵是

So I don't just have the sight of the people in front of me

意識來自於統一的意識場。

and the sound of my voice and the weight of my shoes

因此，我不只是看見眼前的這個人、

against the floor, but they occur to me

我的聲音、我的鞋子在地面上的重量，

as part of one single great conscious field

這些東西都是以

that stretches forward and backward.

前後延伸的單一巨大意識場的一部分

That is the key to understanding

在我心裡出現。

the enormous power of consciousness.

這是了解意識的無窮力量

And we have not been able to do that in a robot.

的關鍵。

The disappointment of robotics derives from the fact

我們還沒有機器人可以做到這件事。

that we don't know how to make a conscious robot,

很遺憾的是，現有的機器人顯示出

so we don't have a machine that can do this kind of thing.

我們還不知道如何製造有意識的機器人，

Okay, the next feature of consciousness,

因此，我們沒有可以做這種事的機器。

after this marvelous unified conscious field,

下一件意識的特徵是，

is that it functions causally in our behavior.

在這個不可思議的統一意識場之後，

I gave you a scientific demonstration by raising my hand,

是它能輕易影響我們的行為。

but how is that possible?

我舉起手，給你們看一項科學的實地示範，

How can it be that this thought in my brain

但是那是怎麼辦到的呢？

can move material objects?

我大腦中的這個想法怎麼

Well, I'll tell you the answer.

能夠搬動實質的物體呢？

I mean, we don't know the detailed answer,

讓我來告訴你答案。

but we know the basic part of the answer, and that is,

我的意思是，我們不知道詳細答案，

there is a sequence of neuron firings,

但是我們知道初步的答案，

and they terminate where the acetylcholine

那就是有一連串的神經活化，

is secreted at the axon end-plates of the motor neurons.

它們會終止在運動神經元終板的軸突

Sorry to use philosophical terminology here,

就是分泌乙醯膽素的地方。

but when it's secreted at the axon end-plates of the motor neurons,

很抱歉我用了一些哲學術語。

a whole lot of wonderful things happen in the ion channels

不過當它在運動神經元的終板分泌時，

and the damned arm goes up.

會有很多美好的事情發生在離子通道中，

Now, think of what I told you.

然後該死的手臂就會舉起來了。

One and the same event,

現在，想想我剛才跟你說過的。

my conscious decision to raise my arm

同樣的一個活動，

has a level of description where it has all of these

我的意識決定要舉起手臂，

touchy-feely spiritual qualities.

在某個程度上這樣的描述

It's a thought in my brain, but at the same time,

隱含了過於情感化的精神特質。

it's busy secreting acetylcholine

那是在我大腦中的一個想法，

and doing all sorts of other things

但是同時也忙著分泌乙醯膽素，

as it makes its way from the motor cortex

還有各式各樣的事，

down through the nerve fibers in the arm.

就好像它自己從運動皮質區

Now, what that tells us is that our traditional vocabularies

透過手臂中的神經纖維來完成的。

for discussing these issues are totally obsolete.

這件事告訴我們，過去

One and the same event has a level of description

用在討論這些議題的字彙都太過時了。

where it's neurobiological, and another level of description

另一種有同樣程度的描述的是

where it's mental, and that's a single event,

在神經生物方面中，

and that's how nature works. That's how it's possible

還有另一種是在心智方面，那是單一的情況，

for consciousness to function causally.

而那是自然如何發生，

Okay, now with that in mind,

它能解釋意識是為何有效運作。

with going through these various features of consciousness,

那麼，把這些記在心上，

let's go back and answer some of those early objections.

記得我剛剛說的這些 關於意識的種種特徵，

Well, the first one I said was, consciousness doesn't exist,

讓我們來解答稍早的問題。

it's an illusion. Well, I've already answered that.

首先我提到的是，意識並不存在，

I don't think we need to worry about that.

意識是錯覺。嗯，我已經回答了。

But the second one had an incredible influence,

我想我們不需要擔心這個問題了。

and may still be around, and that is,

但是第二個問題就有一點出乎意料之外的影響了，

"Well, if consciousness exists, it's really something else.

而且可能問題還是存在，那就是

It's really a digital computer program running in your brain

「如果意識存在，那它真的是別種東西，

and that's what we need to do to create consciousness

那真的是一個在你大腦中運轉的電腦程式，

is get the right program.

那就是我們要做的事，

Yeah, forget about the hardware. Any hardware will do

建立意識就是找到對的程式。