That's how we traveled in the year 1900. That's an open buggy.
这是我们1900年用的交通工具。轻便敞篷马车。
It doesn't have heating. It doesn't have air conditioning.
没有装暖气。也没有装冷气。
That horse is pulling it along at one percent of the speed of sound,
那只马以1%的声速前进，
and the rutted dirt road turns into a quagmire of mud anytime it rains.
而布满车轮痕迹的泥泞小路一下雨就成了沼泽地。
That's a Boeing 707. Only 60 years later, it travels at 80 percent of the speed of sound,
这是波音707客机。只过了60年就能以80%的声速移动，
and we don't travel any faster today because commercial supersonic air travel turned out to be a bust.
而现在我们没有更快的交通工具，因为超音速商务飞机最后失败了。
So I started wondering and pondering, could it be that the best years of American economic growth are behind us?
所以我开始思索会不会美国经济最蓬勃发展的年代已经过去了？
And that leads to the suggestion, maybe economic growth is almost over.
这也意味着，或许经济增长几乎已经结束了。
Some of the reasons for this are not really very controversial.
有些结束的原因没有太大的争议。
There are four headwinds that are just hitting the American economy in the face.
现在有四大困境正迎面袭击美国现在的经济。
They're demographics, education, debt and inequality. They're powerful enough to cut growth in half.
包括人口统计、教育、债务及不平等的问题。这些问题足以减少一半的增长。
So we need a lot of innovation to offset this decline. And here's my theme:
所以我们需要大量创新来抵销经济下滑的趋势。这就是我的主题：
Because of the headwinds, if innovation continues to be as powerful as it has been in the last 150 years, growth is cut in half.
因为这些困境，假如创新的表现能和过去150年一样亮眼，经济增长会减半。
If innovation is less powerful, invents less great, wonderful things, then growth is going to be even lower than half of history.
假如创新力没有进步，无法再发明更多有用的东西，那么经济增长将比不上过去的一半。
Now here's eight centuries of economic growth.
这是过去八个世纪经济增长的表现。
The vertical axis is just percent per year of growth, zero percent a year, one percent a year, two percent a year.
纵轴代表每年增长的百分比，一年0%、1%或2%。
The white line is for the U.K., and then the U.S. takes over as the leading nation in the year 1900, when the line switches to red.
白线代表英国，后段是美国，在1900年成为世界强权，也就是红色线段的部分。
You'll notice that, for the first four centuries, there's hardly any growth at all, just 0.2 percent.
大家可以注意到，前面四个世纪几乎没有任何增长，只有0.2%。
Then growth gets better and better. It maxes out in the 1930s, '40s and '50s,
接着增长越来越快。在20世纪30年代、40年代及50年代达到最高峰，
and then it starts slowing down, and here's a cautionary note.
在这之后，增长速度减慢，这里有一个注意事项。
That last downward notch in the red line is not actual data.
红色线条中最后的下降曲线并非真实的数据。
That is a forecast that I made six years ago that growth would slow down to 1.3 percent.
那只是我在六年前对经济的预测，我那时估计经济增长速度会减缓到1.3%。
But you know what the actual facts are?
但真实数据是如何呢？
You know what the growth in per-person income has been in the United States in the last six years? Negative.
在场有谁知道在过去的六年内美国人均收入增长了多少呢？答案是负增长。
This led to a fantasy. What if I try to fit a curved line to this historical record?
这便导致了一场幻觉。如果我要在这个历史记录中安置一条曲线结果会怎么样呢？
I can make the curved line end anywhere I wanted, but I decided I would end it at 0.2,
我能将曲线终止在任何地方，但我估计会降到0.2%，
just like the U.K. growth for the first four centuries.
就像英国在前四世纪的增长速度一样。
Now the history that we've achieved is that we've grown at 2.0 percent per year over the whole period, 1891 to 2007,
从1891年到2007年，美国经济的年增长率是2.0%，
and remember it's been a little bit negative since 2007.
请记住，2007年以后，经济就出现了负增长。
But if growth slows down, instead of doubling our standard of living every generation,
但如果经济增长速度减慢，结果将不是生活水平比以前翻一番，
Americans in the future can't expect to be twice as well off as their parents, or even a quarter [more well off than] their parents.
未来的美国人民不能期待生活水平比上一代好一倍，或者只是好上四分之一。
Now we're going to change and look at the level of per capita income.
现在我们转来看看人均收入水平。
The vertical axis now is thousands of dollars in today's prices.
纵轴代表以千为单位的美元。
You'll notice that in 1891, over on the left, we were at about 5,000 dollars.
你会发现，在1891年，此图的左半边，美国人均年收入为5000美元。
Today we're at about 44,000 dollars of total output per member of the population.
如今美国人均年收入为44000美元。
Now what if we could achieve that historic two-percent growth for the next 70 years?
如果在1891年后的70年内，经济年增长率为2%呢？
Well, it's a matter of arithmetic. Two-percent growth quadruples your standard of living in 70 years.
这是一个算法问题。2%的经济增长率会让你的生活水平在70年后翻两番。
That means we'd go from 44,000 to 180,000. Well, we're not going to do that, and the reason is the headwinds.
这就意味着美国人均年收入将从44000美元增长到180000美元。然而，我们并不能达到这个目标，原因就在于经济逆风。
The first headwind is demographics.
第一阵经济逆风就是人口。
It's a truism that your standard of living rises faster than productivity, rises faster than output per hour, if hours per person increased.
众所周知，你的生活水平增长速度要快于生产率，也会快于每小时产量，如果人均工时增加。
And we got that gift back in the '70s and '80s when women entered the labor force.
在20世纪70年代和80年代，当女性加入劳动市场，我们的确尝到了甜头。
But now it's turned around. Now hours per person are shrinking, first because of the retirement of the baby boomers,
但是如今形势却出现逆转。人均工时不断缩水，原因之一是五六十年代婴儿潮出生的人目前已面临退休，
and second because there's been a very significant dropping out of the labor force of prime age adult males who are in the bottom half of the educational distribution.
原因之二是青壮年男性劳动力的比例大幅度下降，他们是教育分布的下半部。
The next headwind is education. We've got problems all over our educational system despite Race to the Top.
第二场经济逆风是教育。我们的教育体系存在大量问题，这是除了种族问题之外最严峻的问题。
In college, we've got cost inflation in higher education that dwarfs cost inflation in medical care.
大学里，高等教育的成本增长不断增长，这种增长使医疗保健中的成本增长显得相形见绌。
We have in higher education a trillion dollars of student debt,
高等教育里，学生欠债高达一万亿美元，
and our college completion rate is 15 points, 15 percentage points below Canada.
而大学完成率却低于加拿大15%。
We have a lot of debt. Our economy grew from 2000 to 2007 on the back of consumers massively overborrowing.
我们欠了大量的债务。2000年到2007年间的经济增长是源于消费者的大量过度借贷。
Consumers paying off that debt is one of the main reasons why our economic recovery is so sluggish today.
消费者将钱用于还债，就是如今我们经济萧条的主要原因之一。
And everybody of course knows that the federal government debt is growing as a share of GDP at a very rapid rate,
众所周知，作为GDP的一部分，联邦政府的贷款正在迅速增加，
and the only way that's going to stop is some combination of faster growth in taxes or slower growth in entitlements, also called transfer payments.
而阻止其增长的唯一方式就是加快税收增长以及减缓津贴增长，这也被称作转移支付。
And that gets us down from the 1.5, where we've reached for education, down to 1.3.
若将此种方法付诸实际，就能将我们的教育百分比从1.5%降到1.3%。
And then we have inequality. Over the 15 years before the financial crisis,
除此之外，我们还面临不平等这一问题。在经济危机发生之前的15年内，
the growth rate of the bottom 99 percent of the income distribution was half a point slower than the averages we've been talking about before.
收入分布底层的99%的增长速度比之前我们所讲的平均值降低了0.5%。

All the rest went to the top one percent. So that brings us down to 0.8.
剩下的就是顶层的1%。平均一下，就是0.8%。
And that 0.8 is the big challenge. Are we going to grow at 0.8?
0.8%这个数字对我们来说是个巨大的挑战。我们的经济会以0.8%的速度增长么？
If so, that's going to require that our inventions are as important as the ones that happened over the last 150 years.
要做到这点，我们必须保证今后的发明会与150年前的发明具有同等的重要意义。
So let's see what some of those inventions were.
让我们先来看看过去有哪些发明。
If you wanted to read in 1875 at night, you needed to have an oil or a gas lamp.
在1875年，人们想在晚上读书的话，需要煤油灯或者煤气灯。
They created pollution, they created odors, they were hard to control, the light was dim, and they were a fire hazard.
这些灯会污染环境，也会散发臭味，这种灯很难控制，光线也比较昏暗，同时也是火灾隐患。
By 1929, electric light was everywhere. We had the vertical city, the invention of the elevator.
1929年，电灯在美国已经随处可见了。城市高楼耸立，这个时代又出现了电梯。
Central Manhattan became possible. And then, in addition to that, at the same time,
曼哈顿中央区成为可能。与此同时，
hand tools were replaced by massive electric tools and hand-powered electric tools, all achieved by electricity.
手工操作被大量机械操作取代，手动的电动工具通过电力实现。
Electricity was also very helpful in liberating women.
电力同时也解放了妇女。
Women, back in the late 19th century, spent two days a week doing the laundry.
在十九世纪，妇女每个星期要花两天的时间洗衣服。
They did it on a scrub board. Then they had to hang the clothes out to dry.
她们首先要在搓衣板上刷衣服，然后将衣服挂起来晾干。
Then they had to bring them in. The whole thing took two days out of the seven-day week.
然后再把晒干的衣服带回家。整个过程要花费2天的时间。
And then we had the electric washing machine. And by 1950, they were everywhere.
然后，人类发明了电动洗衣机。1950年，洗衣机在美国随处可见。
But the women still had to shop every day, but no they didn't, because electricity brought us the electric refrigerator.
但是妇女每天要买菜，现在，她们不需要为此操劳了，因为现在有了电冰箱。
Back in the late 19th century, the only source of heat in most homes was a big fireplace in the kitchen that was used for cooking and heating.
在19世纪，大多数家庭里唯一的热源是厨房里用来烧饭和加热的火堆。
The bedrooms were cold. They were unheated. But by 1929, certainly by 1950, we had central heating everywhere.
房间冰冷，没有热源。但到了1929年，尤其到了1950年，中央供暖在美国随处可见。
What about the internal combustion engine, which was invented in 1879?
1879年，人类发明了内燃机。
In America, before the motor vehicle, transportation depended entirely on the urban horse,
在出现汽车之前，美国的交通完全依赖马匹，
which dropped, without restraint, 25 to 50 pounds of manure on the streets every day together with a gallon of urine.
由于没有限制，这些马匹每天在街上要排放25磅至50磅的粪便，还有1加仑的尿液。
That comes out at 5 to 10 tons daily per square mile in cities.
这就意味着每天，城市每平方英尺内就有5到10吨的马排泄物。
Those horses also ate up fully one quarter of American agricultural land.
这些马吃的草占了美国农业土地四分之一。
That's the percentage of American agricultural land it took to feed the horses.
整整25%的美国农业土地居然都用来喂马了。
Of course, when the motor vehicle was invented, and it became almost ubiquitous by 1929,
当然，当汽车出现后，尤其是在1929年汽车遍布全国各地的时候，
that agricultural land could be used for human consumption or for export.
农业土地被用来供人类消费或者出口。
And here's an interesting ratio: Starting from zero in 1900, only 30 years later,
这是个有趣的比例：1900年，没有一个家庭拥有汽车；仅仅三十年之后，
the ratio of motor vehicles to the number of households in the United States reached 90 percent in just 30 years.
90%的美国家庭都拥有了汽车。
Back before the turn of the century, women had another problem.
19世纪末期，妇女还有一个亟待解决的问题。
All the water for cooking, cleaning and bathing had to be carried in buckets and pails in from the outside.
生活用水（例如烧饭，清洁，洗澡），必须从外面一桶一桶地提回来。
It's a historical fact that in 1885, the average North Carolina housewife walked 148 miles a year carrying 35 tons of water.
在1885年，北卡罗来纳州的家庭妇女平均每年要走148英里的路，挑35吨的水。
But by 1929, cities around the country had put in underground water pipes.
但到了1929年，每个城市都安装了地下水管。
They had put in underground sewer pipes, and as a result,
它们也安装了污水管，因为这一发明，
one of the great scourges of the late 19th century, waterborne diseases like cholera, began to disappear.
19世纪末的一大灾难--水传疾病例如霍乱，开始逐渐消失。
And an amazing fact for techno-optimists is that in the first half of the 20th century,
还有一个让技术乐观主义者高兴的事实：在20世纪前半期，
the rate of improvement of life expectancy was three times faster than it was in the second half of the 19th century.
人类寿命的增长速度是19世纪后半期寿命增长速度的三倍。
So it's a truism that things can't be more than 100 percent of themselves.
众所周知，任何事物的增长速度不能超过100%。
And I'll just give you a few examples. We went from one percent to 90 percent of the speed of sound.
在这里我给大家举几个例子：光速从1%提高到90%。
Electrification, central heat, ownership of motor cars, they all went from zero to 100 percent.
电力，中央供暖，汽车拥有量，它们都从0增长到100%。
Urban environments make people more productive than on the farm.
相比农场环境，城市环境提高了人类的生产力。
We went from 25 percent urban to 75 percent by the early postwar years.
二战后期，城市化从25%增长到75%。
What about the electronic revolution? Here's an early computer. It's amazing.
那么电子革命又是如何呢？这是一台早期的电脑。很令人惊讶。
The mainframe computer was invented in 1942. By 1960 we had telephone bills, bank statements were being produced by computers.
电脑的主机产于1942年，到了1960年，人类有了电话账单，银行对账单，这些都是由电脑打印出来的。
The earliest cell phones, the earliest personal computers were invented in the 1970s.
最早的手机、个人电脑，都出现于20世纪70年代。
The 1980s brought us Bill Gates, DOS, ATM machines to replace bank tellers, bar code scanning to cut down on labor in the retail sector.
20世纪80年代出现了比尔·盖茨，磁盘操作系统，自动取款机取代了银行出纳员，条纹扫描削减了销售行业的劳动力。
Fast forward through the '90s, we had the dotcom revolution and a temporary rise in productivity growth.
到了90年代，我们有了网络革命。在生产率有了短暂的提高。
But I'm now going to give you an experiment. You have to choose either option A or option B.
但现在我要给大家展现一个实验，你只能选择A或者B。
Option A is you get to keep everything invented up till 10 years ago.
A选项是：你拥有十年前的所有发明。
So you get Google, you get Amazon, you get Wikipedia, and you get running water and indoor toilets.
你拥有了谷歌、亚马逊、维基百科、自来水、室内洗手间。
Or you get everything invented to yesterday, including Facebook and your iPhone,
B选项是：你拥有直到昨天之前历史上的所有发明，这其中包括脸书、苹果手机，
but you have to give up, go out to the outhouse, and carry in the water.
但是你必须舍弃一些，你只能到屋外上厕所，必须要自己挑水。
Hurricane Sandy caused a lot of people to lose the 20th century, maybe for a couple of days,
台风桑迪使许多人好几天都无法使用20世纪的新发明，
in some cases for more than a week, electricity, running water, heating, gasoline for their cars, and a charge for their iPhones.
在受灾更为严重的地区估计要忍受一个多礼拜，电力，自来水，暖气，汽车所需的汽油，苹果手机的充电器。
The problem we face is that all these great inventions, we have to match them in the future,
我们所面临的的问题是：所有这些伟大的发明都给未来的创新带来挑战，
and my prediction that we're not going to match them brings us down from the original two-percent growth down to 0.2,
我的预测就是，我们不能研制出比这些还要伟大的发明，这就使得我们从2%的增长速度降回了0.2%的增长速度，
the fanciful curve that I drew you at the beginning.
也就是我最开始的时候所画的那条曲线。
So here we are back to the horse and buggy.
所以，我们又回到了最开始的马和敞篷车。
I'd like to award an Oscar to the inventors of the 20th century,
我想给20世纪的所有发明家颁发奥斯卡奖，
the people from Alexander Graham Bell to Thomas Edison to the Wright Brothers,
这些伟人包括亚历山大·格雷厄姆·贝尔一直到托马斯·爱迪生，一直到怀特兄弟，
I'd like to call them all up here, and they're going to call back to you.
我想把他们都邀请到台上来，然后他们将向你们发问。
Your challenge is, can you match what we achieved? Thank you.
你们的挑战是，你们能和我们取得的成就相比吗？谢谢。