We are constantly looking at the world around us,

我們不斷地在檢視生活周遭，

and quickly we identify and make sense of what it is that we see.

並快速地了解和識別我們所看見的東西。

Let's just start with an example of that very fact.

讓我很快地舉例子為大家說明。

I'm going to show you a photograph of a person, just for a second or two,

我會給大家約一至兩秒的時間來看一個人的相片，

and I'd like for you to identify what emotion is on his face.

並且希望你來辨識他臉上的情緒。

Ready?

準備好了嗎？

Here you go. Go with your gut reaction.

來，請跟著自己的感覺。

Okay. What did you see?

好，你看見了什麼？

Well, we actually surveyed over 120 individuals,

這項調查的參與者超過了 120 名，

and the results were mixed.

結果有些混雜。

People did not agree on what emotion they saw on his face.

人們對於他們所看見的臉部情緒判斷的結果完全不一致。

Maybe you saw discomfort.

或許，你看到的是不適，

That was the most frequent response that we received.

這是我們得到最多的回答。

But if you asked the person on your left,

但如果你問坐在你左邊的人，

they might have said regret or skepticism,

他們可能會認為是後悔或懷疑。

and if you asked somebody on your right,

而假設你問坐在右邊的人，

they might have said something entirely different,

或許又是完全不同的反應，

like hope or empathy.

像是希望或有同感。

So we are all looking at the very same face again.

如果我們再一次看同一張臉，

We might see something entirely different,

可能會有全然不同的答案，

because perception is subjective.

因為感覺是很主觀的。

What we think we see is actually filtered through our own mind's eye.

我們以為自己看見的東西，其實是自我意識篩選後的產物。

Of course, there are many other examples of how we see the world through own mind's eye.

當然，還有很多這樣的例子，關於人們如何讓主觀意識去解釋我們身處的世界。

I'm going to give you just a few.

舉幾個例子來說，

So dieters, for instance, see apples as larger than people who are not counting calories.

例如，減肥的人所看到的蘋果會比沒有在計算熱量的人要來得大。

Softball players see the ball as smaller if they've just come out of a slump, compared to people who had a hot night at the plate.

剛走出事業低潮的壘球選手，跟前一晚在場上叱咤風雲的球員比起來，會感覺所看見的壘球更加小。

And actually, our political beliefs also can affect the way we see other people, including politicians.

而事實上人們的政治傾向也會影響到對其他人的觀感，包含了對政治人物的選擇。

So my research team and I decided to test this question.

因此我們的實驗團隊決定用這個問題來進行一個實驗。

In 2008, Barack Obama was running for president for the very first time,

2008年時，巴拉克歐巴馬第一次參選總統。

and we surveyed hundreds of Americans one month before the election.

在大選前一個月，我們訪問了數百位美國人。

What we found in this survey was that some people, some Americans, think photographs like these best reflect how Obama really looks.

在這個調查中我們發現，有些美國群眾認為這組照片充分反映出歐巴馬真實的模樣，

Of these people, 75 percent voted for Obama in the actual election.

而如此認為的受訪者中有 75% 的人在大選中投票給了歐巴馬。

Other people, though, thought photographs like these best reflect how Obama really looks.

也有一部分人認為這組照片才真實反應歐巴馬的樣子，

89 percent of these people voted for McCain.

其中 89% 投給歐巴馬的對手麥肯。

So, we presented many photographs of Obama one at a time,

我們給受訪者觀看歐巴馬的照片，一次一張，

so people did not realize that what we were changing from one photograph to the next was whether we had artificially lightened or darkened his skin tone.

他們其實並不知道兩張照片的不同，差別在我們刻意在膚色上補強光線，使他看起來黝黑。

So how is that possible?

所以這要如何解釋？

How could it be that when I look at a person, an object, or an event, I see something very different than somebody else does?

為何我們看待一個人、一件物品或一個事件，竟然和他人比起來有天與地的差別？

Well, the reasons are many, but one reason requires that we understand a little bit more about how our eyes work.

這其實有很多原因，但我們要先了解視覺的運作方式。

So vision scientists know that the amount of information that we can see at any given point in time, what we can focus on, is actually relatively small.

研究顯示，人們在有限的時間中，以眼睛來攫取資訊，不論我們專注的時間為多久，所得到的資訊其實非常微小。

What we can see with great sharpness and clarity and accuracy is the equivalent of the surface area of our thumb on our outstretched arm.

我們能看到最明顯、最清楚、精確的範圍，大概只有伸長手臂後大拇指這樣的大小，不管我們呈現的內容有多少，

Everything else around that is blurry,

不管我們呈現的內容有多少，

rendering much of what is presented to our eyes as ambiguous.

其餘的影像在眼中看來都是模糊一片。

But we have to clarify and make sense of what it is that we see,

而我們還得去解釋，還要去認識我們看見的東西究竟是什麼。

and it's our mind that helps us fill in that gap.

我們的大腦就是用來幫助我們補足這些空白的。

As a result, perception is a subjective experience,

因此感受是一種主觀的經驗，

and that's how we end up seeing through our own mind's eye.

也是為什麼我們最終感知到的其實是大腦給我們看到的。

So, I'm a social psychologist, and it's questions like these that really intrigue me.

我是社會心理學家，所以我不由得特別關心這樣問題。

I am fascinated by those times when people do not see eye to eye.

我對於人們見山不是山的狀況覺得很有意思。

Why is it that somebody might literally see the glass as half full,

為何有些人看到半杯滿的水，

and somebody literally sees it as half empty?

可有些人看到的是半杯空的水？

What is it about what one person is thinking and feeling that leads them to see the world in an entirely different way?

人們的想法和感覺是如何地影響他以全然不同的角度看待這個世界？

And does that even matter?

就算如此，那又怎樣？

So to begin to tackle these questions, my research team and I decided to delve deeply into an issue that has received international attention: our health and fitness.

於是我們開始研究這些問題，我們實驗小組決定要對這項全球知名的議題進行相關的探討，那就是健康與體態。

Across the world, people are struggling to manage their weight,

無論是哪一個國家，每個人都對控制體重有著深深的困擾。

and there is a variety of strategies that we have to help us keep the pounds off.

各式各樣減重的方式可謂百家爭鳴。

For instance, we set the best of intentions to exercise after the holidays,

舉例來說，每到假期結束，我們就拼了命減肥。

but actually, the majority of Americans find that their New Year's resolutions are broken by Valentine's Day.

但事實上，大部分的美國人會發現，他們的新年新希望在情人節之前就落空了。

We talk to ourselves in very encouraging ways,

我們想方設法地激勵自己，

telling ourselves this is our year to get back into shape,

告訴自己就在今年，我們可以恢復以往的身材。

but that is not enough to bring us back to our ideal weight.

然而這並不足以帶我們重返往日的理想體重。

So why?

為什麼會這樣呢？

Of course, there is no simple answer, but one reason, I argue, is that our mind's eye might work against us.

答案當然沒那麼簡單，但我認為其中一項原因，就是我們的大腦可能背叛了我們。

Some people may literally see exercise as more difficult,

有些人就是覺得運動很困難，

and some people might literally see exercise as easier.

有些人就覺得運動其實很簡單。

So, as a first step to testing these questions,

所以，為了能進一步地探索這些疑問，

we gathered objective measurements of individuals' physical fitness.

我們首先要量取每位受測者的身材。

We measured the circumference of their waist, compared to the circumference of their hips.

我們拿腰圍和臀圍的比例來做比較，

A higher waist-to-hip ratio is an indicator of being less physically fit than a lower waist-to-hip ratio.

腰臀比相對較高的表示體態較差，反之，比較低的表示體態較好。

After gathering these measurements,

取得這些數據後，

we told our participants that they would walk to a finish line while carrying extra weight in a sort of race.

我們告訴受測者他們要帶著重物走到終點線，這是項比賽。

But before they did that,

比賽前，

we asked them to estimate the distance to the finish line.

我們請受測者評估一下到終點的距離。

We thought that the physical states of their body might change how they perceived the distance.

我們的想法是：體態的不同會影響人們對於距離的感知。

So what did we find?

那我們發現了什麼呢？

Well, waist-to-hip ratio predicted perceptions of distance.

就是腰臀比的差異的確會有距離感知上的不同。

People who were out of shape and unfit actually saw the distance to the finish line as significantly greater than people who were in better shape.

體格不勻稱的受測者和體態較好的受測者比起來，認為終點的距離較遠得多。

People's states of their own body changed how they perceived the environment.

體態的差異使人們對環境有不同的感受，

But so too can our mind.

而我們的意識也一樣。

In fact, our bodies and our minds work in tandem to change how we see the world around us.

事實上，我們的身心共同運作，來改變我們對所處環境的看法。

That led us to think that maybe people with strong motivations and strong goals to exercise might actually see the finish line as closer than people who have weaker motivations.

這讓我們聯想到，或許有強烈動機及有明確目標可尋的人，相較於動機比較弱的人，會感覺終點近些。

So to test whether motivations affect our perceptual experiences in this way, we conducted a second study.

因此，我們又進行了第二項實驗，來探究動機的強弱是否會影響我們的經驗感受。

Again, we gathered objective measurements of people's physical fitness,

同樣地，我們還是先量取每位受測者的身材，

measuring the circumference of their waist and the circumference of their hips,

取得腰圍和臀圍的數據，

and we had them do a few other tests of fitness.

並且請他們做一些體格的量測。

Based on feedback that we gave them,

根據我們給對方的反饋，

some of our participants told us they're not motivated to exercise any more.

有些受測對象表示他們不想健身。

They felt like they already met their fitness goals and they weren't going to do anything else.

他們感覺已經達到身材標準了，因此不願意再做任何的運動。

These people were not motivated.

這些人沒有運動的動機。

Other people, though, based on our feedback, told us they were highly motivated to exercise.

相反地，根據我們的反饋，其他人則告訴我們他們極願意去運動健身。

They had a strong goal to make it to the finish line.

他們有明確目標，認為可達到終點。

But again, before we had them walk to the finish line, we had them estimate the distance.

再一次地，我們要求他們在出發前估算一下

How far away was the finish line?

終點線到底多遠。

And again, like the previous study, we found that waist-to-hip ratio predicted perceptions of distance.

而結果也一如先前的研究，我們發現腰臀比的確影響距離感知。

Unfit individuals saw the distance as farther, saw the finish line as farther away, than people who were in better shape.

體格較差的人覺得距離較遠，相較於體格較好的人，會覺得終點線遠在天邊。

Importantly, though, this only happened for people who were not motivated to exercise.

重點來了，這樣的結果只發生在沒有健身動力的人身上。

On the other hand,

相反地，

people who were highly motivated to exercise saw the distance as short.

具強烈動機想運動的人認為終點線近在眼前，

Even the most out of shape individuals saw the finish line as just as close, if not slightly closer, than people who were in better shape.

即使是體態最差的人，所推估的終點距離也和體態較好的人推估的相去不遠，就算距離沒有更短，也非常接近了。

So our bodies can change how far away that finish line looks,

所以我們的體態會影響到我們認知的終點距離。

but people who had committed to a manageable goal that they could accomplish in the near future and who believed that they were capable of meeting that goal actually saw the exercise as easier.

然而，忠力於可視的目標、認為自己短期內可完成、也相信自己有能力可以實現目標的人，卻認為運動是件容易的事。

That led us to wonder,

這不禁讓我們思考：

is there a strategy that we could use and teach people that would help change their perceptions of the distance, help them make exercise look easier?

有沒有一種方法可以讓我們用來教導並協助他人改變對距離的感知呢？能否幫助他們感覺運動其實很簡單？

So we turned to the vision science literature to figure out what should we do,

於是我們尋求視覺科學研究的幫助，思索我們該怎麼做。

and based on what we read, we came up with a strategy that we called, "Keep your eyes on the prize."

而根據這個領域的研究，我們有了一個想法，就是「盯著眼前的蘿蔔」。

So this is not the slogan from an inspirational poster.

這可不是激勵人心的海報文案，

It's an actual directive for how to look around your environment.

對於如何看待自身所處的環境，這是最直截了當的做法。

People that we trained in this strategy, we told them to focus their attention on the finish line, to avoid looking around, to imagine a spotlight was shining on that goal, and that everything around it was blurry and perhaps difficult to see.

用這個理論來訓練的對象，被告知要緊盯著終點線，不要左顧右盼。想像那個目標被燈光聚焦壟罩著，而旁邊的景物一片朦朧，模糊難辨。

We thought that this strategy would help make the exercise look easier.

我們認為這個方法可以讓運動看起來容易一點。

We compared this group to a baseline group.

我們將這個實驗組和對照組做比較。

This group we said, just look around the environment as you naturally would.

我們告訴對照組要張望周遭的環境，就像平常會做的一樣。

You will notice the finish line,

你會看到終點線，

but you might also notice the garbage can off to the right,

也會看到右手邊的垃圾桶，

or the people and the lamp post off to the left.

還有行人及左手邊的路燈。

We thought that people who used this strategy would see the distance as farther.

我們認為用這種方法看終點線的人會感覺距離比較遠。

So what did we find?

那麼結論呢？

When we had them estimate the distance, was this strategy successful for changing their perceptual experience?

當我們要求兩組去評估距離，這樣的策略是否成功地改變人們的感知經驗呢?

Yes.

是的。

People who kept their eyes on the prize saw the finish line as 30 percent closer than people who looked around as they naturally would.

緊盯著目標的人，和東張西望的對照組比起來，對於終點線的感知足足短了三成。

We thought this was great.

這真是太棒了！

We were really excited because it meant that this strategy helped make the exercise look easier,

相當振奮人心，我們知道這個策略可以使運動看起來比較容易。

but the big question was, could this help make exercise actually better?

但問題是，這個方法可以讓運動的效果更好嗎？

Could it improve the quality of exercise as well?

能進一步提升運動的品質嗎？

So next, we told our participants, you are going to walk to the finish line while wearing extra weight.

接下來，我們告訴受測對象，你得戴著重物走去終點。

We added weights to their ankles that amounted to 15 percent of their body weight.

我們在腳踝綁上與受測者體重 15% 等同的重物，

We told them to lift their knees up high and walk to the finish line quickly.

告訴他們抬起膝蓋走路，快步走向終點。

We designed this exercise in particular to be moderately challenging but not impossible,

我們刻意將這個實驗設計成有點難度，但並非做不到的程度，

like most exercises that actually improve our fitness.

就像一般的健身運動一樣。

So the big question, then:

那麼接下來的問題是：

Did keeping your eyes on the prize and narrowly focusing on the finish line change their experience of the exercise?

緊盯眼前目標，聚焦終點這個方法，真的能改變人們對於運動的體驗嗎？

It did.

的確如此。

People who kept their eyes on the prize told us afterward that it required 17 percent less exertion for them to do this exercise than people who looked around naturally.

緊盯目標的受測者後來表示，如果拿他們和四處張望的對照組比較起來的話，他們為達到目標所花的心力少了 17%。

It changed their subjective experience of the exercise.

這改變了他們本身對運動的體驗，

It also changed the objective nature of their exercise.

也改變了他們對運動本質的看法。

People who kept their eyes on the prize actually moved 23 percent faster than people who looked around naturally.

把重點放在最後獎勵的人，較於其他不專注的人，竟可以提升 23% 的速度。

To put that in perspective, a 23 percent increase is like trading in your 1980 Chevy Citation for a 1980 Chevrolet Corvette.

用個簡單的例子來說明，23% 的速度差別幾乎是等同於你拿二、三十年的老爺車跟跑車來比。

We were so excited by this,

這樣的結果讓人相當興奮，

because this meant that a strategy that costs nothing, that is easy for people to use, regardless of whether they're in shape or struggling to get there, had a big effect.

因為這個理論告訴我們，我們可以不花半毛錢，也不費吹灰之力，不論是胖是瘦，或正掙扎於減重道路上的人，這一策略都有顯著的效果。

Keeping your eyes on the prize made the exercise look and feel easier even when people were working harder because they were moving faster.

把眼光放在最後的勝利果實上，會使運動感到輕鬆許多，也會讓人們更努力，因為他們的進展變快了。

Now, I know there's more to good health than walking a little bit faster,

當然，並不是走得快一點，就會變得比較健康。

but keeping your eyes on the prize might be one additional strategy that you can use to help promote a healthy lifestyle.

然而，把眼光放在獎賞的這個策略，或許是你可以用來建立健康人生的方法之一。

If you're not convinced yet that we all see the world through our own mind's eye, let me leave you with one final example.

請讓我最後再舉一個例子。如果以上論點還不足以讓你相信我們其實是用大腦在看這個世界，

Here's a photograph of a beautiful street in Stockholm, with two cars.

這張照片是斯德哥爾摩的一條漂亮街道，街上面有兩部車，

The car in the back looks much larger than the car in the front.

後面那部看起來比前面的大。

However, in reality, these cars are the same size, but that's not how we see it.

但是實際上，兩部車是一樣大的。可我們看到的卻不是這樣。

So does this mean that our eyes have gone haywire and that our brains are a mess?

那麼，是我們頭昏眼花了嗎？腦筋秀逗了嗎？

No, it doesn't mean that at all.

不是的，才不是這樣。

It's just how our eyes work.

人的眼睛就是這樣運作的，

We might see the world in a different way,

我們可能用不同的視角去看這個世界，

and sometimes that might not line up with reality,

或許有時它脫離了現實，

but it doesn't mean that one of us is right and one of us is wrong.

但這不代表誰對誰錯。

We all see the world through our mind's eye,

我們都是以自身的意識在看待一切，

but we can teach ourselves to see it differently.

但我們可以教導自己從不同的角度去看問題。

So I can think of days that have gone horribly wrong for me.

我可以把日子看成奇糟無比，

I'm fed up, I'm grumpy, I'm tired, and I'm so behind, and there's a big black cloud hanging over my head,

我受夠了，又氣、又累，一敗塗地，每天頭頂都是烏雲籠罩。

and on days like these, it looks like everyone around me is down in the dumps too.

在這樣的日子裡，好像身旁的每個人都跟我一樣處於低潮。

My colleague at work looks annoyed when I ask for an extension on a deadline,

當我請求延遲一下工作交件日期時，同事看起來很煩躁。

and my friend looks frustrated when I show up late for lunch because a meeting ran long,

當我因開會而在午餐約會上遲到，我的朋友看起來有點不爽。

and at the end of the day, my husband looks disappointed because I'd rather go to bed than go to the movies.

然後在一天結束之際，我老公很沮喪，因為我寧願休息也不願陪他去看電影。

And on days like these, when everybody looks upset and angry to me,

每當我遇上這種時運不濟、每個人都好像對我不爽的日子，

I try to remind myself that there are other ways of seeing them.

我會試著提醒自己用不同的角度去看待世界。

Perhaps my colleague was confused, perhaps my friend was concerned, and perhaps my husband was feeling empathy instead.

或許我同事覺得很困惑，或許我的朋友其實是關心我，也許我老公能理解我的狀況。

So we all see the world through our own mind's eye,

我們都是用自我意識在觀看生活。

and on some days, it might look like the world is a dangerous and challenging and insurmountable place,

在某些日子裡，我們的世界看起來既危險又困難艱辛。

but it doesn't have to look that way all the time.

但我們不需要一直用負面的眼光來看待一切，

We can teach ourselves to see it differently,

我們可以教自己換個角度。

and when we find a way to make the world look nicer and easier, it might actually become so.

當我們能夠找到一個讓世界看起來比較友善的方法時，世界或許就會變得不同。

Thank you.

謝謝各位！

(Applause)

（掌聲）