in something that's actually one of the oldest questions in economics,

世界的な金融危機を受けて また関心を集めていることがあります

dating back to at least before Adam Smith.

経済学においては最も古く 少なくとも ―

And that is, why is it that countries with seemingly similar economies and institutions

アダム・スミス以前から続く問いです

can display radically different savings behavior?

「経済活動や制度が類似する国々で 貯蓄行動が大いに異なるのは何故か」

Now, many brilliant economists have spent their entire lives working on this question,

「経済活動や制度が類似する国々で 貯蓄行動が大いに異なるのは何故か」

and as a field we've made a tremendous amount of headway

聡明な経済学者たちが一生をかけ 答えを追求してきました

and we understand a lot about this.

その甲斐あって 議論は大きく前進してきましたし

What I'm here to talk with you about today is an intriguing new hypothesis

多くのことが明らかになりました

and some surprisingly powerful new findings that I've been working on

今日ご紹介するのは 私が研究している新たな仮説と

about the link between the structure of the language you speak

言語の構造と 貯蓄傾向の関連性についての

and how you find yourself with the propensity to save.

言語の構造と 貯蓄傾向の関連性についての

Let me tell you a little bit about savings rates, a little bit about language,

驚くほど大きな新発見です

and then I'll draw that connection.

貯蓄率や言語について 簡単に説明した後

Let's start by thinking about the member countries of the OECD,

その 関連性を紐解いていきます

or the Organization of Economic Cooperation and Development.

まずは OECD 経済協力開発機構の ―

OECD countries, by and large, you should think about these

加盟国について考えてみましょう

as the richest, most industrialized countries in the world.

OECD諸国は概して 裕福な先進工業国と言えるでしょう

And by joining the OECD, they were affirming a common commitment

OECD諸国は概して 裕福な先進工業国と言えるでしょう

to democracy, open markets and free trade.

また OECDに加盟する以上 民主主義や自由市場 ―

Despite all of these similarities, we see huge differences in savings behavior.

自由貿易に取り組むという 意思を表明しています

So all the way over on the left of this graph,

こうした共通点はありますが 貯蓄傾向は大きく異なっています

what you see is many OECD countries saving over a quarter of their GDP every year,

このグラフの左の方をご覧いただくと

and some OECD countries saving over a third of their GDP per year.

多くのOECD諸国では毎年 GDPの４分の１以上を貯蓄しています

Holding down the right flank of the OECD, all the way on the other side, is Greece.

３分の１以上を 貯蓄に回している国もあります

And what you can see is that over the last 25 years,

反対側を見ていくと 右端はギリシャです

Greece has barely managed to save more than 10 percent of their GDP.

ここ25年以上 ギリシャの貯蓄率は

It should be noted, of course, that the United States and the U.K. are the next in line.

辛うじてGDPの10%を越える程度で 推移してます

Now that we see these huge differences in savings rates,

もちろんアメリカとイギリスが そのすぐ隣にいることも見逃せません

how is it possible that language might have something to do with these differences?

さて こうした貯蓄率における違いに

Let me tell you a little bit about how languages fundamentally differ.

言語が関係している可能性が あるのでしょうか

Linguists and cognitive scientists have been exploring this question for many years now.

言語間には根本的な相違があり ―

And then I'll draw the connection between these two behaviors.

その相違点について 言語学者や 認知科学者が研究を重ねてきました

Many of you have probably already noticed that I'm Chinese.

このことが後で貯蓄の話に 関連してきます

I grew up in the Midwest of the United States.

お気づきかと思いますが 私は中国人です

And something I realized quite early on

アメリカの中西部で育ちました

was that the Chinese language forced me to speak about and --

幼少期に あることに気付いたんです

in fact, more fundamentally than that --

中国語で家族のことを話そうとすると

ever so slightly forced me to think about family in very different ways.

そもそも思考の段階から

Now, how might that be? Let me give you an example.

英語とは違うのだということです

Suppose I were talking with you and I was introducing you to my uncle.

具体的な例を挙げますね

You understood exactly what I just said in English.

例えば 皆さんを私の「おじ」に 紹介するとしましょう

If we were speaking Mandarin Chinese with each other, though,

英語では "uncle" で 問題ありませんね

I wouldn't have that luxury.

しかし これが中国語だと

I wouldn't have been able to convey so little information.

そう簡単には済みません

What my language would have forced me to do,

情報が足りないのです

instead of just telling you, "This is my uncle,"

中国語では「おじ」に

is to tell you a tremendous amount of additional information.

膨大な情報を付与しなければ

My language would force me to tell you

何を言っているか伝わらないのです

whether or not this was an uncle on my mother's side or my father's side,

「おじ」と言っても

whether this was an uncle by marriage or by birth,

それが母方なのか 父方なのか

and if this man was my father's brother,

血縁なのか 姻戚なのか

whether he was older than or younger than my father.

父方であれば

All of this information is obligatory. Chinese doesn't let me ignore it.

父の兄なのか 弟なのか

And in fact, if I want to speak correctly,

これらは全て中国語では 無視できない必須項目です

Chinese forces me to constantly think about it.

中国語で正確に話そうとすると

Now, that fascinated me endlessly as a child,

このような事を 考えざるを得ないのです

but what fascinates me even more today as an economist

私はこういうことで 延々と楽しめる子でしたが

is that some of these same differences carry through to how languages speak about time.

今日 経済学者として 私が心をつかまれるのは

So for example, if I'm speaking in English, I have to speak grammatically differently

「時」についても 言語間で同様の相違があるという点です

if I'm talking about past rain, "It rained yesterday,"

例えば 英語を話す場合には 文法に違いが出ます

current rain, "It is raining now,"

過去なら "It rained yesterday"

or future rain, "It will rain tomorrow."

現在ならば "It is raining now"

Notice that English requires a lot more information with respect to the timing of events.

未来は "It will rain tomorrow"

Why? Because I have to consider that

英語では事象のタイミングについて 情報が不可欠です

and I have to modify what I'm saying to say, "It will rain," or "It's going to rain."

いつ言うかによって

It's simply not permissible in English to say, "It rain tomorrow."

未来形に変える必要が出てくるのです

In contrast to that, that's almost exactly what you would say in Chinese.

"It rain tomorrow" は 英語では許されません

A Chinese speaker can basically say something

ところが中国語では それでいいのです

that sounds very strange to an English speaker's ears.

英語では奇妙でも

They can say, "Yesterday it rain," "Now it rain," "Tomorrow it rain."

中国語なら大丈夫です

In some deep sense, Chinese doesn't divide up the time spectrum

過去でも現在でも未来でも "It rain" と言って構いません

in the same way that English forces us to constantly do in order to speak correctly.

つまり中国語には 英語のような時制の区切りがないのです

Is this difference in languages

つまり中国語には 英語のような時制の区切りがないのです

only between very, very distantly related languages, like English and Chinese?

英語と中国語の関係が 特別に薄いせいでしょうか？

Actually, no.

英語と中国語の関係が 特別に薄いせいでしょうか？

So many of you know, in this room, that English is a Germanic language.

違います

What you may not have realized is that English is actually an outlier.

ご存じのとおり 英語はゲルマン語派ですが

It is the only Germanic language that requires this.

実は英語には例外的な特徴があります

For example, most other Germanic language speakers

ゲルマン語派で時制があるのは 英語だけです

feel completely comfortable talking about rain tomorrow

英語以外のゲルマン語派では

by saying, "Morgen regnet es,"

明日の雨について "Morgen regnet es" つまり ―

quite literally to an English ear, "It rain tomorrow."

明日の雨について "Morgen regnet es" つまり ―

This led me, as a behavioral economist, to an intriguing hypothesis.

"It rain tomorrow" と言って 差し支えありません

Could how you speak about time, could how your language forces you to think about time,

行動経済学者である私は ある面白い仮説を思いつきました

affect your propensity to behave across time?

「時」についての捉え方や 言語的な制約が

You speak English, a futured language.

いつの間にか 行動傾向にも 影響しているのではないか？

And what that means is that every time you discuss the future,

英語には未来形がありますから

or any kind of a future event,

皆さんが英語で 将来について話す場合には

grammatically you're forced to cleave that from the present

皆さんが英語で 将来について話す場合には

and treat it as if it's something viscerally different.

文法的に現在から切り離す必要があり

Now suppose that that visceral difference

直感的に遠いものと見なします

makes you subtly dissociate the future from the present every time you speak.

その遠いものという感覚が

If that's true and it makes the future feel

英語を使うたびに 現在と将来を切り離していくとすると

like something more distant and more different from the present,

将来というものは

that's going to make it harder to save.

現在から遠く離れたものに感じられ

If, on the other hand, you speak a futureless language,

貯蓄する気が薄れます

the present and the future, you speak about them identically.

未来形のない言語では

If that subtly nudges you to feel about them identically,

現在と未来が一体化しています

that's going to make it easier to save.

日頃から現在と未来を同一視していると

Now this is a fanciful theory.

貯蓄する気になりやすいのです

I'm a professor, I get paid to have fanciful theories.

これは突飛な理論ですが

But how would you actually go about testing such a theory?

私は大学教授なので これも仕事のうちです

Well, what I did with that was to access the linguistics literature.

実際に理論を検証する方法を考え

And interestingly enough, there are pockets of futureless language speakers

言語学の文献を当たりました

situated all over the world.

面白いことに 世界には 未来形のない言語を話す地域が

This is a pocket of futureless language speakers in Northern Europe.

固まって存在しているのです

Interestingly enough, when you start to crank the data,

北欧のこの地域の言語には 未来の概念がありません

these pockets of futureless language speakers all around the world

面白いことに データを見ていくと

turn out to be, by and large, some of the world's best savers.

未来の概念のない言語を話す人々と

Just to give you a hint of that,

高額の貯蓄を持つ人々が ほぼ一致することがわかりました

let's look back at that OECD graph that we were talking about.

ヒントはこれです

What you see is that these bars are systematically taller

先程のOECDのグラフに 戻りましょう

and systematically shifted to the left

貯蓄率の高い国は体系的に 左に寄っています

compared to these bars which are the members of the OECD that speak futured languages.

貯蓄率の高い国は体系的に 左に寄っています

What is the average difference here?

未来形のある言語を話す国と 比べると こうです

Five percentage points of your GDP saved per year.

平均差を求めてみると

Over 25 years that has huge long-run effects on the wealth of your nation.

貯蓄率の違いは 年間でGDPの５％ずつなので

Now while these findings are suggestive,

25年経てば国の資産に 莫大な影響を与えることになります

countries can be different in so many different ways

何か関係ありそうな気配ですが

that it's very, very difficult sometimes to account for all of these possible differences.

国ごとの違いというのは

What I'm going to show you, though, is something that I've been engaging in for a year,

内容が多岐に渡りますから 一概には言えません

which is trying to gather all of the largest datasets

そこで 私がここ１年 研究してきたことをご紹介します

that we have access to as economists,

経済学者の持てる ありとあらゆるデータを駆使し

and I'm going to try and strip away all of those possible differences,

経済学者の持てる ありとあらゆるデータを駆使し

hoping to get this relationship to break.

国ごとの違いを極力排除して

And just in summary, no matter how far I push this, I can't get it to break.

相関関係はないと証明したいのですが

Let me show you how far you can do that.

結論から言って 相関を認めざるを得ません

One way to imagine that is I gather large datasets from around the world.

検証過程を説明しましょう

So for example, there is the Survey of Health, [Aging] and Retirement in Europe.

たとえば世界中から 大量のデータを集めます

From this dataset you actually learn that retired European families

「欧州における 健康・加齢・退職の調査」を見ると

are extremely patient with survey takers.

ヨーロッパの退職者世帯は このような調査に対し ―

(Laughter)

非常に忍耐強いことがわかります

So imagine that you're a retired household in Belgium and someone comes to your front door.

（笑）

"Excuse me, would you mind if I peruse your stock portfolio?

退職してベルギーに家を構えたとします 誰かが訪ねてきて

Do you happen to know how much your house is worth? Do you mind telling me?

「すみません 持ち株の明細を見せてもらえませんか？

Would you happen to have a hallway that's more than 10 meters long?

お宅の価格をご存じですか？ 教えてもらえます？

If you do, would you mind if I timed how long it took you to walk down that hallway?

10メートル以上の廊下はありますか？

Would you mind squeezing as hard as you can, in your dominant hand, this device

その廊下をあなたが何秒で歩くか 計ってもいいですか？

so I can measure your grip strength?

利き手でこの装置を思いっきり 握ってもらえますか？

How about blowing into this tube so I can measure your lung capacity?"

握力を測りますから

The survey takes over a day.

このチューブに息を吹き込んでください 肺活量を測ります」

(Laughter)

調査は一日以上を続きます

Combine that with a Demographic and Health Survey

（笑）

collected by USAID in developing countries in Africa, for example,

さらにUSAIDによる アフリカの途上国の ―

which that survey actually can go so far as to directly measure the HIV status

「人口保健調査」も資料に加えます

of families living in, for example, rural Nigeria.

たとえばナイジェリアの 農村部の世帯のHIV感染状況まで

Combine that with a world value survey,

調べているような資料です

which measures the political opinions and, fortunately for me, the savings behaviors

「世界価値観調査」も使えます

of millions of families in hundreds of countries around the world.

世界のあらゆる国で 何百万もの世帯の政治的見解や ―

Take all of that data, combine it, and this map is what you get.

ラッキーなことに貯蓄行動まで 調べてある資料です

What you find is nine countries around the world

そうしたデータを全て組み合わせると こうなります

that have significant native populations

ご覧の９カ国では ―

which speak both futureless and futured languages.

未来形のある言語とない言語 その両方が使われています

And what I'm going to do is form statistical matched pairs

未来形のある言語とない言語 その両方が使われています

between families that are nearly identical on every dimension that I can measure,

ここから 評価が可能な条件について

and then I'm going to explore whether or not the link between language and savings holds

類似するデータを組み合わせて 統計分析のためにペアを作ります

even after controlling for all of these levels.

条件を揃えた上で 言語と貯蓄率の間に

What are the characteristics we can control for?

関連性があるかどうか 調べるというわけです

Well I'm going to match families on country of birth and residence,

コントロールできる特性は

the demographics -- what sex, their age --

生まれ育った国

their income level within their own country,

性別や年齢などの属性

their educational achievement, a lot about their family structure.

各国の基準で見た所得レベル

It turns out there are six different ways to be married in Europe.

学歴や家族構成の詳細です

And most granularly, I break them down by religion

欧州では結婚の形態だけで ６種類もありますから

where there are 72 categories of religions in the world --

さらに 宗教によって細分化しました

so an extreme level of granularity.

世界には72の宗教分類がありますから

There are 1.4 billion different ways that a family can find itself.

非常に細かくなりますね

Now effectively everything I'm going to tell you from now on

世帯ごとの属性は 全部で14億種類に分類されます

is only comparing these basically nearly identical families.

ここでは 特性が類似する世帯を抽出し

It's getting as close as possible to the thought experiment

比較した内容だけを抜粋してお話します

of finding two families both of whom live in Brussels

ほとんど思考実験のようなものです

who are identical on every single one of these dimensions,

言語以外の属性が全て共通する ―

but one of whom speaks Flemish and one of whom speaks French;

ブリュッセル在住の２世帯で

or two families that live in a rural district in Nigeria,

一方はフレミッシュ語 他方はフランス語

one of whom speaks Hausa and one of whom speaks Igbo.

あるいはナイジェリアの 農村部の２世帯で

Now even after all of this granular level of control,

一方はハウサ語 他方はイボ語という具合です

do futureless language speakers seem to save more?

このように細かく条件を絞り込んで 分析した場合

Yes, futureless language speakers, even after this level of control,

未来形のない言語話者の方が 貯蓄が多いか？

are 30 percent more likely to report having saved in any given year.

その通り 任意の年に 「貯蓄した」と回答する確率は

Does this have cumulative effects?

未来形のない言語を話す人の方が 30％高いのです

Yes, by the time they retire, futureless language speakers, holding constant their income,

累積効果も見られます

are going to retire with 25 percent more in savings.

未来形のない言語を話す人々は 退職までに所得を継続的に貯蓄し

Can we push this data even further?

退職時点での貯蓄は 25％多くなっています

Yes, because I just told you, we actually collect a lot of health data as economists.

さらに掘り下げてみましょう

Now how can we think about health behaviors to think about savings?

せっかく健康に関するデータが 手元にありますから

Well, think about smoking, for example.

貯蓄のことを念頭において 健康面でどうしているか

Smoking is in some deep sense negative savings.

たとえば喫煙について見てみましょう

If savings is current pain in exchange for future pleasure,

喫煙は ある意味 マイナスの貯蓄です

smoking is just the opposite.

貯蓄は「将来の喜び」と引き換えの 「現在の苦しみ」

It's current pleasure in exchange for future pain.

喫煙は逆です

What we should expect then is the opposite effect.

「将来の苦しみ」に変わる 「現在の喜び」

And that's exactly what we find.

それなら 効果も逆になりそうですよね

Futureless language speakers are 20 to 24 percent less likely

実際その通りでした

to be smoking at any given point in time compared to identical families,

未来形のない言語を話す人は そうでない人と比べ

and they're going to be 13 to 17 percent less likely

どの時期においても約20～24％ 喫煙率が低く

to be obese by the time they retire,

退職までに肥満になる確率も

and they're going to report being 21 percent more likely

13～17％低く

to have used a condom in their last sexual encounter.

最近のセックスでコンドームを 使った割合は21％高いという結果でした

I could go on and on with the list of differences that you can find.

最近のセックスでコンドームを 使った割合は21％高いという結果でした

It's almost impossible not to find a savings behavior

こうした数値的な差は 枚挙に暇がありません

for which this strong effect isn't present.

強い統計的効果なくして 貯蓄行動なしと言っても

My linguistics and economics colleagues at Yale and I are just starting to do this work

過言ではないでしょう

and really explore and understand the ways that these subtle nudges

言語学者で経済学者でもある イェール大学の仲間と共に

cause us to think more or less about the future every single time we speak.

言語を使うたび 将来の捉え方に 知らず知らずのうちに影響を及ぼす ―

Ultimately, the goal,

その仕組みを解明すべく 本格的に研究を始めました

once we understand how these subtle effects can change our decision making,