ダニエル・カーネマン: 経験と記憶の謎

Daniel Kahneman: The riddle of experience vs. memory

YouTube 動画

YouTube 動画




Everybody talks about happiness these days. 
最近 幸福について話す人が多いですね 

I had somebody count the number of books with "happiness" in the title published in the last five years
過去5年に出版され タイトルに“幸福”が 入っている本を ある人に数えてもらったところ

and they gave up after about 40, and there were many more.
あまりの量で 40冊ほどで諦めてしまいました 

There is a huge wave of interest in happiness, among researchers. 
研究者たちの幸福に対する興味の高まりは かなりのものです

There is a lot of happiness coaching.

Everybody would like to make people happier.

But in spite of all this flood of work, 
しかし そのような努力があるにも関わらず

there are several cognitive traps that sort of make it almost impossible to think straight about happiness.
幸福について 明瞭に考えることを ほぼ不可能にしてしまう認知の罠が 幾つかあります

And my talk today will be mostly about these cognitive traps. 
今日は この認知の罠を取り上げます

This applies to laypeople thinking about their own happiness, 

and it applies to scholars thinking about happiness,

because it turns out we're just as messed up as anybody else is. 
なぜなら 誰もが混乱した状態にいるからです

The first of these traps is a reluctance to admit complexity. 
罠の一つは 複雑さを認めることへの抵抗感にあります

It turns out that the word "happiness" is just not a useful word anymore, 
幸福という言葉は もはや役立つ言葉ではない―という事が明らかになりました

because we apply it to too many different things. 
この言葉を様々な事に あてはめすぎるからです 

I think there is one particular meaning to which we might restrict it,but by and large, 
この言葉には 特定の意味合いがありますが 概して 狭い意味に

this is something that we'll have to give up and we'll have to adopt the more complicated view of what well-being is. 
限定することは諦めて  幸福な状態とは何か もっと複雑な見方を しなくてはいけないのです

The second trap is a confusion between experience and memory;
二つめの罠は 体験と記憶を混同してしまうことです

basically, it's between being happy in your life, and being happy about your life or happy with your life.
 生活の中で見いだす幸福と 自分の人生の幸福度合い この違いです

And those are two very different concepts, 

and they're both lumped in the notion of happiness.

And the third is the focusing illusion,

and it's the unfortunate fact that we can't think about any circumstance that affects well-being without distorting its importance. 
幸福の状態を左右する状況を ゆがめて考えてしまうのは 残念なことです

I mean, this is a real cognitive trap. 
これは まさに認知の罠です 

There's just no way of getting it right.

Now, I'd like to start with an example of somebody who had a question-and-answer session after one of my lectures reported a story, 
例を出してみましょう 私の講義の後におこなった質疑応答で

and that was a story 

-- He said he'd been listening to a symphony,

and it was absolutely glorious music and at the very end of the recording,
その音楽に聞き惚れていたところ その曲の終わりに

there was a dreadful screeching sound. And then he added,

really quite emotionally, it ruined the whole experience.
彼はかなり感情的に 曲が台無しになった と言いました

But it hadn't. What it had ruined were the memories of the experience.
でも 台無しになったのは 曲ではなく その経験の記憶です

He had had the experience. He had had 20 minutes of glorious music.
彼は素晴らしい曲を 20分聴いていたのに 

They counted for nothing because he was left with a memory;
その価値がなくなったのは 台無しになった記憶が 残ったからです

the memory was ruined, and the memory was all that he had gotten to keep.

What this is telling us, really, is that we might be thinking of ourselves and of other people in terms of two selves.
この話から 我々が 自らを二つの自己として 考えているらしいとわかります

There is an experiencing self, who lives in the present and knows the present,is capable of re-living the past,
経験の自己― これは 現在を生き 現在を経験し 過去にも戻れる自己です

but basically it has only the present.

It's the experiencing self that the doctor approaches -- you know, when the doctor asks,"Does it hurt now when I touch you here?"
例えば 医師が “ここを触ったら痛みますか?”と尋ねる相手は 経験の自己です

And then there is a remembering self,
そして 記憶の自己というのがあります

and the remembering self is the one that keeps score, and maintains the story of our life,
記憶の自己とは 記録を残し 人生の物語を紡ぎます

and it's the one that the doctor approaches in asking the question,
  医師が尋ねる質問を 例に出すと 

"How have you been feeling lately?" 

or "How was your trip to Albania?"

or something like that. 

Those are two very different entities,
この二つは まったく異なるもので

the experiencing self and the remembering self,

and getting confused between them is part of the mess about the notion of happiness.
混同してしまうのは 幸福の観念に見られる 混乱なのです

Now, the remembering self is a storyteller.
記憶の自己は 語り手です

And that really starts with a basic response of our memories -- it starts immediately.
我々の記憶の基本的な反応で すぐに動き出します

We don't only tell stories when we set out to tell stories.
話をするとき 我々が単純に語っているのではなく

Our memory tells us stories,

that is, what we get to keep from our experiences is a story.
要は経験から 引き継がれたものが 話になるのです

And let me begin with one example. 

This is an old study. 

Those are actual patients undergoing a painful procedure.

I won't go into detail. It's no longer painful these days,

but it was painful when this study was run in the 1990s. 

They were asked to report on their pain every 60 seconds.
患者は60秒ごとに 痛みの度合いを報告するように言われ

Here are two patients, those are their recordings. And you are asked,
これは二人の患者と 彼らの痛みを記録したものです

"Who of them suffered more?" And it's a very easy question.
この二人のうち より苦しんだのは どちらかと聞かれたら

Clearly,Patient B suffered more
明らかに それは患者Bですね

-- his colonoscopy was longer,

and every minute of pain that Patient A had, Patient B had, and more.
患者Aが毎分感じた痛み以上に 患者Bは痛みを感じました

But now there is another question:
さて 別の質問をします

"How much did these patients think they suffered?"
患者自身に どれだけ苦しんだと思うかと尋ねると

And here is a surprise.

The surprise is that Patient A had a much worse memory of the colonoscopy than Patient B.
患者Bよりも 患者Aのほうが より嫌な記憶として 覚えていたのです

The stories of the colonoscopies were different, 

and because a very critical part of the story is how it ends.
なぜなら その話の一番重要な部分は 検査の終わり方なのです

And neither of these stories is very inspiring or great 
どちらの話も 心を打たれるような内容ではありませんが

-- but one of them is this distinct ... (Laughter) but one of them is distinctly worse than the other.
 一方は もう片方よりも 明らかに悲惨なものなのです

And the one that is worse is the one where pain was at its peak at the very end;
より嫌な記憶として語られた方は まさに終わるときに痛みがピークを迎えていました

it's a bad story.

How do we know that? Because we asked these people after their colonoscopy, and much later, too,
対象となった患者には 検査後と かなり時間が経ってから インタビューしました 

"How bad was the whole thing, in total?" And it was much worse for A than for B, in memory.
検査全体の印象を評価してもらうと 患者Bよりも 患者Aが より大変だったと答えました

Now this is a direct conflict between the experiencing self and the remembering self.
これは経験の自己と記憶の自己の間で起こる はっきりとした矛盾です   

From the point of view of the experiencing self, 

clearly, B had a worse time. Now, what you could do with Patient A,

and we actually ran clinical experiments, and it has been done, and it does work 
患者Aにどうすべきだったか 実際に行った臨床実験で 効果が確かめられているのですが

-- you could actually extend the colonoscopy of Patient A by just keeping the tube in without jiggling it too much.
患者Aのチューブをそれほど動かさず 大腸内視鏡検査を長引かせます 

That will cause the patient to suffer, 

but just a little and much less than before.
その痛みは ほんの少しで それまでに比べて 痛みは激減します

And if you do that for a couple of minutes, you have made the experiencing self of Patient A worse off,
これを数分やれば 患者Aの経験の自己には つらい思いをさせますが

and you have the remembering self of Patient A a lot better off,
記憶の自己には ずっとましな処置です

because now you have endowed Patient A with a better story about his experience.
なぜなら 患者Aに与えた 経験の物語は ましなものになっているからです

What defines a story? 

And that is true of the stories that memory delivers for us, and it's also true of the stories that we make up.
これは記憶を通して我々が思い出す話や 我々が作り上げる話にも共通したことです

What defines a story are changes, 
話を明確にするものは 変化であり

significant moments and endings.
決定的な瞬間であり 結末なのです

Endings are very, very important and, in this case, 

the ending dominated.

Now, the experiencing self lives its life continuously.
さて 経験の自己の 人生には切れ目もなく

It has moments of experience, one after the other.
どんな瞬間でも 次から次へと経験をしています

And you can ask: What happens to these moments? 

And the answer is really straightforward:

They are lost forever.

I mean, most of the moments of our life

-- and I calculated, you know, the psychological present is said to be about three seconds long;
心理的現在は 約3秒だと 言われており

that means that, you know,

in a life there are about 600 million of them; in a month,there are about 600,000
その3秒は 人生で約6億回 月に約60万回もある計算になりますが

-- most of them don't leave a trace. 

Most of them are completely ignored by the remembering self.
ほとんどが記憶の自己に 無視されてしまいます

And yet, somehow you get the sense that they should count, 
それでもどういうわけか 今この瞬間には価値があり 

that what happens during these moments of experience is our life. 
そこで起きている事こそが 人生であると感じるのです

It's the finite resource that we're spending while we're on this earth. 
我々が生きる間に体験できる― 限られたものであり

And how to spend it would seem to be relevant, 
人生をいかに過ごすかということが 価値を持つように感じますが

but that is not the story that the remembering self keeps for us.
これは記憶の自己が 残す話とは違うのです

So we have the remembering self and the experiencing self,and they're really quite distinct.
記憶の自己と経験の自己とは まったく別物なのです

The biggest difference between them is in the handling of time.
 一番の違いは 時間の扱い方です 

From the point of view of the experiencing self, 

if you have a vacation,

and the second week is just as good as the first, 
1週目も2週目も 同じくらい楽しければ

then the two-week vacation is twice as good as the one-week vacation.
2週間の休暇の充足感は 1週間の休暇の2倍です

That's not the way it works at all for the remembering self. For the remembering self,

a two-week vacation is barely better than the one-week vacation 
 2週間の休暇は 1週間の休暇と さほど変わらないのです

because there are no new memories added.

You have not changed the story. 

And in this way,

time is actually the critical variable that distinguishes a remembering self from an experiencing self;
時間は記憶の自己と 経験の自己を区別する― 重要なポイントです

time has very little impact on the story.
この休暇の例に 時間はあまり影響力はありません

Now, the remembering self does more than remember and tell stories.
記憶の自己は 話を記憶し 語ること以上の働きがあります

It is actually the one that makes decisions because, 
 実際に 決断をするのは記憶の自己です

if you have a patient who has had, say,
例えば 大腸内視鏡検査を2回 二人の医師から受けた患者に

two colonoscopies with two different surgeons and is deciding which of them to choose,

then the one that chooses is the one that has the memory that is less bad, and that's the surgeon that will be chosen.
その患者は 記憶の中で ましだった方の 医師を選びます

The experiencing self has no voice in this choice.
この選択をする際 経験の自己は関わっていません

We actually don't choose between experiences, we choose between memories of experiences.
通常 我々は経験から選ぶ事はせず 記憶から選び出します

And even when we think about the future, we don't think of our future normally as experiences.
未来のことを考える時でさえ 経験として考える事は 普通ありません

We think of our future as anticipated memories.
先を見越した記憶として 未来を見ています

And basically you can look at this, you know, as a tyranny of the remembering self,
これは記憶の自己による 専制政治と考えてください

and you can think of the remembering self sort of dragging the experiencing self through experiences that the experiencing self doesn't need.
記憶の自己が決めて 経験の自己に対して 望んでいたわけでもない事も 経験させるのです

I have that sense that when we go on vacations this is very frequently the case;
私が感じるのは 我々が休暇に出かけるのは ―大半のケースに言えますが

that is, we go on vacations, to a very large extent, in the service of our remembering self. 
休暇とは 記憶の自己のために 行くものだという気がします 

And this is a bit hard to justify I think.

I mean, how much do we consume our memories?

That is one of the explanations that is given for the dominance of the remembering self.
これは 記憶の自己が 支配している― 説明の一つです

And when I think about that,

I think about a vacation we had in Antarctica a few years ago,

which was clearly the best vacation I've ever had, 

and I think of it relatively often, relative to how much I think of other vacations.
その他の旅行に比べて 思い出す回数も多いのです

And I probably have consumed my memories of that three-week trip,I would say, for about 25 minutes in the last four years. 
その3週間の旅行を 過去4年のうちに思い出したのは 25分程度でしょう

Now, if I had ever opened the folder with the 600 pictures in it,
もしも 600枚の写真を 見返したとしたら 

I would have spent another hour.

Now, that is three weeks, and that is at most an hour and a half.
3週間の旅行に対し せいぜい1時間半の記憶なので 

There seems to be a discrepancy. 

Now,I may be a bit extreme, you know, in how little appetite I have for consuming memories,
私は平均的な人ほど 記憶を思い返すことをしないのかもしれませんが

but even if you do more of this, there is a genuine question:
もっと頻繁に記憶にアクセスしたとしても 真の疑問が残ります

Why do we put so much weight on memory relative to the weight that we put on experiences?
なぜ経験と比べて 記憶に重きを置くのでしょうか?

So I want you to think about a thought experiment.
ここで ある思考実験をしてみましょう

Imagine that for your next vacation, you know that at the end of the vacation all your pictures will be destroyed,
皆さんの次の休暇で 休暇の最後になって 全ての写真が削除されるとします

and you'll get an amnesic drug so that you won't remember anything.

Now, would you choose the same vacation? (Laughter) 

And if you would choose a different vacation,
それでも その休暇を選ぶでしょうか?

there is a conflict between your two selves, 
もし別の休暇にするならば 二つの自己が対立しているので

and you need to think about how to adjudicate that conflict,

and it's actually not at all obvious, 
実際のところ わかりづらいんです

because if you think in terms of time,

then you get one answer, 

and if you think in terms of memories, you might get another answer.
記憶を優先すれば 別の答えが出てくるかもしれません

Why do we pick the vacations we do is a problem that confronts us with a choice between the two selves.
なぜ その休暇を選んでいるかという 二つの自己の間にある選択肢は 我々が直面する問題です

Now, the two selves bring up two notions of happiness.
二つの自己は 二つの幸福の観念をもたらします

There are really two concepts of happiness that we can apply, one per self.
二つの自己に対して適用できる― 幸福の観念がひとつずつあるのです

So you can ask: How happy is the experiencing self?
そこで出てくる質問は “経験の自己はどれだけ幸せなのか?”

And then you would ask: How happy are the moments in the experiencing self's life? And they're all
そして “経験の自己の人生において どれだけ幸せを感じているのか?”

-- happiness for moments is a fairly complicated process.
幸福に感じる瞬間とは 非常に複雑なプロセスです

What are the emotions that can be measured?

And, by the way, now we are capable of getting a pretty good idea of the happiness of the experiencing self over time.
経験の自己が感じる幸福と 時間の関係性は わかっていただけたと思います

If you ask for the happiness of the remembering self,
もし 記憶の自己の幸福を尋ねるとしたら

it's a completely different thing. 

This is not about how happily a person lives.
これは ある人がどれだけ幸せに暮らしているか ということではなく

It is about how satisfied or pleased the person is when that person thinks about her life.
その人が自分の人生を考えたときに どれだけ満足しているかということです

Very different notion. 

Anyone who doesn't distinguish those notions is going to mess up the study of happiness,
この観念の違いがわからなければ 幸福の研究はうまくいきません

and I belong to a crowd of students of well-being,who've been messing up the study of happiness for a long time in precisely this way.
私は まさにこんな感じに 長い間 幸福の研究がうまくいかずにいる― 学者の1人です

The distinction between the happiness of the experiencing self and the satisfaction of the remembering self has been recognized in recent years,
経験の自己の幸福と記憶の自己の満足感が 違うという事実は 近年 気づかれるようになってきました

and there are now efforts to measure the two separately.
現在では 二つを隔てて測る努力もされています 

The Gallup Organization has a world poll where more than half a million people have been asked questions about what they think of their life and about their experiences,
ギャラップは 50万人を対象に 世界中で世論調査を行い 自分の人生と経験を どう思っているかアンケートを行いました

and there have been other efforts along those lines. So in recent years,
そして それに沿った形で 他の調査も進んできました

we have begun to learn about the happiness of the two selves.
近年では 二つの自己に絡んだ幸福に関して 解明し始めたところです

And the main lesson I think that we have learned is they are really different.
我々が学んだ主なことは 二つがまったく別物だということです

You can know how satisfied somebody is with their life,

and that really doesn't teach you much about how happily they're living their life, and vice versa.
そこから その人が どれだけ人生を幸せに過ごしているかはわかりません   反対のことも言えます

Just to give you a sense of the correlation, the correlation is about .5.
その相関性を示してみます 相関性は約0.5です

What that means is if you met somebody, and you were told,"Oh his father is six feet tall," 
例えば 父の身長が180cmだと ある人が言ったとしても

how much would you know about his height? Well,

you would know something about his height,

but there's a lot of uncertainty. 
多少の目安にはなりますが はっきりしたことはわかりません

You have that much uncertainty.

If I tell you that somebody ranked their life eight on a scale of ten,
ある人が 自分の人生は10点満点中8点だと言ったとしても

you have a lot of uncertainty about how happy they are with their experiencing self.
どれだけ経験の自己が 幸せなのか 推しはかることはできません

So the correlation is low.

We know something about what controls satisfaction of the happiness self.
幸福に対する満足度を支配する要素は わかっています

We know that money is very important, goals are very important.
お金は大切ですし 目標も大切 

We know that happiness is mainly being satisfied with people that we like,
幸福とは主に 好きな人と共に 満足することであり

spending time with people that we like. 

There are other pleasures,

but this is dominant. 

So if you want to maximize the happiness of the two selves,
ですから 二つの自己の幸福度を強めたい場合は

you are going to end up doing very different things.
まったく異なる事柄を する事になるでしょう

The bottom line of what I've said here is that we really should not think of happiness as a substitute for well-being.
要は 幸福は心身ともに健全でいることと  同じ事だと考えるべきではないのです

It is a completely different notion.

Now, very quickly, 

another reason we cannot think straight about happiness is that we do not attend to the same things when we think about life, and we actually live.
幸福を考える時 これほど複雑化する もう1つの理由は 人生に関して考えるときと実際に生きている日々とでは 我々は同じことに注目していないということです

So, if you ask the simple question of how happy people are in California,
ですから カリフォルニアの人たちに幸せの度合いを尋ねても 

you are not going to get to the correct answer.

When you ask that question,

you think people must be happier in California if, say, you live in Ohio. (Laughter) 
カリフォルニアのほうが幸せなはずだと思うのです 例えばオハイオの人なんかね (笑)

And what happens is when you think about living in California,
ここで起きるのは カリフォルニアで暮らす事を考える時

you are thinking of the contrast between California and other places, 
カリフォルニアと別の場所を 対比させて考える ということです

and that contrast, say, is in climate.
例えば 気候の違いです

Well, it turns out that climate is not very important to the experiencing self and it's not even very important to the reflective self that decides how happy people are.
実は 気候というのは 経験の自己には重要ではなく 人がどれだけ幸せなのかを決める

But now, because the reflective self is in charge,
記憶の自己にも それほど重要ではありません

you may end up -- some people may end up moving to California.
しかし 記憶の自己がつかさどっているので  中には カリフォルニアへ 引っ越す人が出るのです

And it's sort of interesting to trace what is going to happen to people who move to California in the hope of getting happier.
幸せになるだろうと期待してカリフォルニアへ 移り住む人たちに何が起こるのか 追跡するのは興味深いんです

Well, their experiencing self is not going to get happier. 
経験の自己が 一層幸せになる事はありません

We know that.

But one thing will happen: They will think they are happier, because,
でも確実に言えるのは 彼らがもっと幸せだと思うようになる事です

when they think about it, they'll be reminded of how horrible the weather was in Ohio,
なぜなら 彼らはオハイオの天気が どれだけ悪かったか思い出し

and they will feel they made the right decision.

It is very difficult to think straight about well-being,
心身ともに健全でいることを  事実どおりに考えるのは非常に難しいのです

and I hope I have given you a sense of how difficult it is.
どれだけ難しいことなのか わかってもらえたでしょうか

Thank you.

Chris Anderson: Thank you. I've got a question for you. Thank you so much.
ありがとう 質問がありますどうもありがとう

Now, when we were on the phone a few weeks ago,

you mentioned to me that there was quite an interesting result came out of that Gallup survey.
世論調査で浮かび上がった非常に興味深い 結果を教えてくれましたね

Is that something you can share since you do have a few moments left now?
時間があるので お話してくれませんか もちろんです

Daniel Kahneman: Sure. I think the most interesting result that we found in the Gallup survey is a number,

which we absolutely did not expect to find.

We found that with respect to the happiness of the experiencing self.
経験の自己から見る幸福に関し 分かったのは

When we looked at how feelings, vary with income.
我々の感情は 収入と密接に 関わっていることです

And it turns out that, below an income of 60,000 dollars a year, for Americans
ここで明らかになったのは アメリカ人にとって 年収6万ドル以下は

-- and that's a very large sample of Americans, like 600,000,

so it's a large representative sample --

below an income of 600,000 dollars a year...
年収60万ドル以下だと… 6万ドルですね?

CA: 60,000.

DK: 60,000. (Laughter) 60,000 dollars a year,
そうそう 6万ドル (笑) 年収6万ドル以下だと 

people are unhappy, 

and they get progressively unhappier the poorer they get.
金額が下がるほど その度合いは増します 

Above that, we get an absolutely flat line. 

I mean I've rarely seen lines so flat.

Clearly, what is happening is money does not buy you experiential happiness,
明らかに ここで言える事は 経験的な幸福をお金で買うことはできませんが

but lack of money certainly buys you misery, 
お金がないのと 惨めな思いをするということです

and we can measure that misery very, very clearly. 
その惨めさをはっきりと 測ることもできます

In terms of the other self, the remembering self, you get a different story.

The more money you earn, the more satisfied you are.
お金を儲けるほど 満足感は増す 

That does not hold for emotions.

CA: But Danny, the whole American endeavor is about life, liberty, the pursuit of happiness. 
でもアメリカ人が頑張るのも 生活 自由 幸福の追求のためですよね? 

If people took seriously that finding,
もし 皆がその調査結果を真剣に受け止めたら

I mean, it seems to turn upside down everything we believe about, like for example,
 私たちが信じる全てを 180度転換するような感じがします

taxation policy and so forth. Is there any chance that politicians, that the country generally,
例えば 税制に関してとか… 政治家が この調査結果を真剣に受け止めて

would take a finding like that seriously and run public policy based on it?
この基盤に基づいて公共政策を動かす事は 今後あるでしょうか?

DK: You know I think that there is recognition of the role of happiness research in public policy.
公共政策の中で 幸福の研究も 位置づけられていると思います

The recognition is going to be slow in the United States, no question about that, 
アメリカでの認知度向上には 間違いなく 時間がかかるでしょう

but in the U.K., it is happening, and in other countries it is happening.
イギリスや他国では 認知度が高まっていて

People are recognizing that they ought to be thinking of happiness when they think of public policy.
公共政策を考える際 幸福を視野に入れる必要性が 考慮されています

It's going to take a while, and people are going to debate whether they want to study experience happiness,
時間はかかりますし 幸福の経験の研究や 生活の評価の研究に関して 議論がなされるでしょう

or whether they want to study life evaluation, 

so we need to have that debate fairly soon.

How to enhance happiness goes very different ways depending on how you think,
幸福の高め方は その人の考え方によって異なりますし

and whether you think of the remembering self or you think of the experiencing self.
記憶の自己や経験の自己のどちらを 考えるかによっても異なります

This is going to influence policy, I think, in years to come.
これは今後 政策に影響するでしょう

In the United States,

efforts are being made to measure the experience happiness of the population.
全国民の経験的な幸福を 測る努力がされています

This is going to be, I think,

within the next decade or two, part of national statistics.
今後10~20年以内に これは国家統計の 一部になると思います

CA: Well, it seems to me that this issue will -- or at least should be
この問題は 今後数年の間

-- the most interesting policy discussion to track over the next few years.
一番興味深い政策論議に なりそうですね

Thank you so much for inventing behavioral economics.
行動経済学を生み出してくれて ありがとう 

Thank you, Danny Kahneman.


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