Placeholder Image

字幕表 動画を再生する

  • My name is Joel Cohen I’m Professor of Populations at the Rockefeller

  • University and at Columbia University in New York City.  

  • My background is partially in public health and partially in applied mathematics.

  • WHY SHOULD YOU STUDY DEMOGRAPHY? Why should you consider taking a course in

  • demography in college? 

You will be growing up in the generation where the baby boomers

  • are going into retirement and dying.  You will face problems in the aging of the population

  • that have never been faced before. 

You will hear more and more about migration into

  • the United States and in some cases, out, into Europe and out between rural areas and

  • cities.

You need to understand as a citizen and as a tax payer and as a voter what’s

  • really behind the arguments.  

INTRODUCTION TO PROBLEMS IN DEMOGRAPHY

I want to tell

  • you about the past, present and future of the human population.  So let’s start with

  • a few problems. Right now, a billion people are chronically hungry.  That means they

  • wake up hungry, theyre hungry all day and they go to sleep hungry.  A billion people

  • are living in slums, not the same billion people, but there is some overlap.  Living

  • in slums means they don’t have tenure in their homes, they don’t have infrastructure

  • to take the garbage away, they don’t have secure water supplies to drink.  

  • Nearly a billion people are illiterate.  Try to imagine your life being illiterate.  You

  • can’t read the labels on the bottles in the supermarket, if you can get to a supermarket.

  •  Two-thirds of those people who are illiterate are women and about 200 to 215 million women

  • don’t have access to the contraceptives they want so that they can control their own

  • fertility.   This is not only a problem in developing countries;

  • about half of all pregnancies are unintended. So those are examples of population problems.

  •   DEMOGRAPHY AS A TOOL FOR SOLUTIONS

  • Demography gives you the tools to address and to understand these problems.  It’s

  • the study of populations of humans and non-human species that includes viruses like influenza,

  • the bacteria in your gut, plants that you eat, animals that you enjoy or that provide

  • your domestic animals.  And it includes non-living objects like light bulbs, and taxi cabs and

  • buildings because these are also populations.  And it includes the study of these populations

  • in the past, present and future using quantitative data and mathematical models as tools of analysis.

  •   I see demography as a central subject related

  • to economics, to human wellbeing as in material terms; related to the environment, to the

  • wellbeing of the other species with which we share the planet; and the wellbeing and

  • culture which affects our values and how we interact with one another. 

WORLD POPULATION:

  • THE PAST The key fact you need to remember, is that

  • since the inventions of agriculture between 6,000 and 14,000 years ago, the population

  • of the earth, the human population, has grown 1,000 fold from approximately seven million

  • to nearly seven billion this year.  Put three zeroes on the end of seven million, you get

  • seven billion.   Over the same interval, the earth has not

  • gotten any bigger.  The continents haven’t expanded 1,000 fold or at all.  The oceans

  • are the same size as they were before.  The atmosphere is the same size as it was before.

  •  So the question that concerns a lot of people and me is whether the impacts that seven billion

  • people or more in the future will have on the earth will endanger, will threaten our

  • own well being and the well being of other species on the earth.  We know that humans

  • have already caused the extinction of many species.  The question is, is that going

  • to come back and bite us, and if so, in what ways?  

  • Demography provides us with a reliable way to imagine and to reimagine the future.  So

  • let’s get down to some nitty-gritty details here.   About 2,000 years ago, there were

  • roughly a quarter of a billion people on the planet.  Today, there are almost seven billionMore

  • than six-seventh of the growth since the beginning of humans 50,000 years ago has occurred in

  • the last 200 years.   To go from a quarter of a billion to half

  • a billion took 16 centuries.  So we reached about half a billion humans about 1600, more

  • or less.  The population of the earth, the human population, if it were growing exponentially

  • would go from a quarter billion to half in 16 centuries and from half to one in another

  • 16 centuries.   What actually happened was that the human

  • population of the earth reached a billion around 1800.  Why?  Because of food stuffs

  • that came from the New World to the old; notably potato and corn or maize.  And because many

  • of the people who were overcrowded in Europe went to America where there were fertile and

  • unoccupied lands to use.  So the East/West exchange, the Columbian exchange across the

  • Atlantic liberated population growth in the European sector, there was a similar development

  • in Japan, an acceleration of population growth around the same time.  

  • In 1800, the Industrial Revolution began and the population doubled from one billion to

  • two billion by 1930, 1927, we don’t know exactly.  Why don’t we know exactly?  Because

  • we didn’t have censuses that covered the whole world at that time.  So it’s a retrospective

  • guess.   So our doubling times went from 1,600 years

  • to 200 years, 1600 to 1800, to 130 years, 1800 to 1930.  The next doubling from two

  • billion to four billion took only 44 years, 1974. 

So for

  • the last 2,000 years at least, except for the Black Death in the 14th century, the population

  • growth rate was going up, up, up, up and around 1965, it began

  • to decline.   So in absolute terms and in percentage terms,

  • the number of people we are adding to the planet has begun to slow.   

  • FERTILITY IS THE KEY TO UNDERSTANDING HUMAN POPULATION

Since 1950, humans have made

  • the swiftest, voluntary change in reproduction in human history.  Around 1950 the average

  • number of children per woman, per lifetime was very close to five.  Today, the average

  • number of children per woman is about 2.5 or 2.6.  In other words, billions of people

  • have changed their reproductive behavior to lower the number of children born in a lifetime

  • from five to two-and-a-half, but not everywhere.  

  • In Sub-Saharan Africa, the decline has been much less.  From perhaps 6.6 children to

  • 5.1 over the halfthe second half of the 21st century.  To understand the consequences

  • of this fall to two-and-a-half children per woman, you need to know what is meant by replacement

  • level fertility.   So I am going to introduce that by telling

  • you about the theory of bathtubs.  A regular bathtub with no stopper.  So two things happen

  • with a bathtub with no stopper.  Water comes in and water goes out.  And you can see intuitively

  • that if the amount of water coming in per minute exceeds the amount of water going out

  • per minute, the level of water in the bathtub is going to go up, and if the amount of water

  • come in per minute is less than the amount being drained out, the level in the bathtub

  • is going to go down.  So the amount of water coming in that just matches the amount going

  • out keeps the level of the bathtub steady.  Okay?  That’s replacement level bathtub

  • water.  

Now, water coming in corresponds to births to the earth.  And water going

  • out corresponds to death.  And the level of the bathtub corresponds to the total population

  • size.  So, if the number of births just matches the number of deaths, the population stays

  • steady and that’s the replacement level of fertility.  

Now, youre asking

  • yourself, what is the replacement level of fertility?  The answer is, it’s about 2.1

  • children per woman. There has been an amazing transformation in

  • the distribution of fertility across the world.

In 2003, this was not in any newspaper anywhere,

  • but it was a very important event.  In 2003, half of all the women in the world were having

  • replacement level or less.   And now more than half of humanity lives in a country at

  • or below replacement level fertility.  It’s the first time in human history that this

  • has happened.  And it’s important.  But you remember that the total fertility rate,

  • the average number of children per woman is at 2.5, not 2.1.  And that’s because on

  • this curve, the green curve, the folks with high fertility are further to the right of

  • the red line than most of the folks with low fertility are to the left.  So the average

  • is skewed to the right.  So we still have a growing population.  But this change is

  • continuing and how fast it continues is something that you as voters, as potential scientists,

  • as citizens will influence by what you choose to do about the 215 million women who have

  • an unmet need for contraception.   WORLD POPULATION: THE PRESENT

  • So much for the past, let’s go on to the present. This is a population pyramid.  It

  • is one of the basic descriptive tools of demography and you should understand what it is.  Let’s

  • start with the left side of the picture.   The horizontal axis, the width of the bar

  • tells you how many people there are and the vertical axis correspondence to age group.

  •  So the lowest bar is for people aged zero to four with males on the left and females

  • on the right.  The next bar is people age five to nine. The top bar is 95 to 100.  And

  • what you see is that in the rich countries, there are about as many people aged, let’s

  • say zero to four as there are aged 85 or 90, but it’s basically a slender column.  

  • Now compare it with the age pyramid for the poor countries.  The base of the pyramid

  • is enormous compared to the number of elderly.  So there are many more workers to support

  • the elderly, per elderly person.  The width of the bar, again is the number of people,

  • so in the ranges from five to 14 of five to 19, that’s the school age population.  It

  • means that the challenge of educating those children is much greater in the developing

  • countries than it is in the rich countries because those bars keep getting wider as the

  • developing countries pump in more children at the bottom of the pyramid and the age groups

  • move up with time as they get older. And so the larger school age population is followed

  • 10 years later by a much larger military age population.  

  • So if you look at the age groups 19 to 30 or 15 to 30, whatever the legal ages or illegal

  • ages are for fighting, you can see that the potential military force in the developing

  • countries vastly exceeds that in the rich countries.  It doesn’t mean it’s military

  • power for them, it means they can afford a military engagement in a way that the human

  • resources of the rich countries make very difficult, increasingly difficult.  

  • So where is the growth going?  The demographic growth is happening in the countries that

  • can least afford to deal with the additional population.  

  • What’s the average income?  The reason we call a rich country as rich is that their

  • average income is about $32,000 a year per person and in the poor countries it is about

  • $5,000 a year.   What fraction of people are living on less

  • than $2.00 a day?  Nobody lives on less than $2.00 a day in the rich countries and 51 percent,

  • just about half in the poor countries.  In other words, about 3.5 billion people on our

  • planet are living on $2.00 a day or less. So you might ask yourself, if things are so

  • bad there how is it that their population is growing so rapidly?  And the fact is that

  • the difference in death rates is much smaller than the difference in fertility rates.  So

  • even though a higher fraction of children die before they reproduce, the average number

  • of children that people have when they do reproduce in the poor countries more than

  • compensates for the increase in the death rate.  So that’s why we have rapid population

  • growth at the same time that we have high fertility, high mortality because we had even

  • higher fertility.   The global economic inequality means that

  • the most rapid demographic growth is associated with the people who have the least means to

  • take care of the children that are born and the people with the greatest need for reproductive

  • healthcare and services have the least means to afford it.  

  • It’s an important general question, How does the rich world benefit from the prosperity

  • and development of the poor world?  There are lots of different answers you can give.

  •  One is, purely economic.  Richer people in China and Africa will buy more American

  • music CD’s and more movies and more software and more high tech engines from General Electric

  • and more products because they have more means to buy.  So that’s one kind of an answer.

  •   A second is public health.  There are millions

  • of flights in both directions from the poor countries to the rich countries every year.

  • And the microbes don’t know about passports.  And they cross from Bombay or Mumbai to

  • New York just a fast as they go from New York to Mumbai.  And when there are outbreaks

  • of drug resistant tuberculosis, those can travel around the world and they pose a danger

  • to me and to you guys.  So we have an interest in the health and well being.  A direct,

  • personal interest in the health and well-being of people in poor countries.

  • WORLD POPULATION: THE FUTURE So now weve talked about the demographic

  • past, and the demographic present.  And next were gonna talk about the demographic future.

  •   Woody Allen said, “Eternity is very long,

  • especially near the end.”  So, were not going to talk about eternity.  We are

  • only going to talk about the near term future.  How much of the future is relevant to you?

  •  Well, according to the United States Life Tables, published by the National Center for

  • Health Statistic.  An 18-year-old in the United States in the year 2011 has a 91 percent

  • chance of surviving to 2050, 91 percent.  Based on survival rates in 2006.  If you behave

  • wisely and if economic and medial progress continues, you have at least that good a chance

  • of making it to 2050.  So were going to talk about the world from now to 2050.  

  • I can say with confidence that four things will happen over the next 40 years or so.

  •  The world’s population will get bigger.  It will grow more slowly.  It will be older

  • in the sense that the fraction of older people will increase dramatically and it will be

  • more urban. And I’m going to go through each of those four to explain some of the

  • details.   What we don’t know too much about is what

  • will be the future of migration, the future of household structures, and the future of

  • families.  We have some ideas about that, but that’s relatively less certain.  

  • THE FUTURE OF THE WORLD’S POPULATION : BIGGER This graph shows four different curves of

  • the history and future population out to 2050.  At the top, the curve shows the anticipated

  • population if fertility remains at the level it is today and there’s no further decline

  • in fertility.  That’s called the Constant Fertility Assumption.  And it shows that

  • the world would go to about 11 billion people by 2050.  However, if fertility drops as

  • it has dropped in the past, the medium projection of the U.N. Population Division is that population

  • would rise to about 9.1 billion by 2050.  So that’s a difference of two billion.  In

  • other words, were counting on a continuing decline in fertility to lower the population

  • size by about two billion by 2050.  

What we do between now and 2050 will have a huge

  • impact on how difficult it is to feed, house, shelter, educate, and provide health for the

  • billions of people on the planet in 2050.  It will affect an enormous range of human

  • problems.   It’s possible that population growth would

  • end before 2100 depending on the choices we make now.  What choices am I talking about?

  •  Choices like, educating women, providing credit to women in countries where women are

  • not now allowed to have credit. Providing reproductive healthcare so that women are

  • not forced as they are in some countries to have children when they don’t want to.  Raising

  • the age of marriage so that 12-year-olds, 13-year-olds and 14-year-olds aren’t put

  • into marriage.   There’s a lot of things we can do to raise people, including even

  • women, raise people’s control over their own lives.  And we should be doing those

  • things. 

I am not trying to persuade people not to have children.  I think that

  • is nuts, but I am trying to persuade people to have children that they can take care of

  • and do well for and to focus on quality of children rather than numbers.  And, I view

  • demography rather broadly so I think you also need to know how your body works, how contraception

  • works, what’s more reliable, what’s less reliable, what are the factors that affect

  • contraception and how to take care of your own reproductive health and to help your children

  • take care of their reproductive health and your friends and your family.

  • THE FUTURE OF THE WORLD’S POPULATION : SLOWER GROWTH

  • So the first fact about the future is that the population is going to get bigger and

  • the second fact is that the population is going to grow more slowly dependingthe

  • slowing will depend on what we do now.    By 2050 in the medium projection from the

  • United Nations Population Division, the world will be growing by 31 million people a year.

  •   What’s it doing now? It’s growing by 76

  • million people a year. In the poor countries, the population will

  • be growing by 32 million a year while in the rich countries; the population will actually

  • be declining by a million people a year.  Already today

  • in 2011, population is declining in more than 50 countries.  Not well-known.

  • What’s happening here is a shift in childbearing desires and action from quantity to quality

  • as people urbanize, as people get educated, as wealth improves, people are making greater

  • investments in a smaller number of children.  

  • THE FUTURE OF THE WORLD’S POPULATION : OLDER So weve talked about population size, growth

  • rate, slowing.  The next is aging.  

So by 2050, there will be about three times as

  • many elderly as children.  This is the first time in human history that the elder population

  • has outnumbered the young population. So what?  Well, aging affects energy demand.

  •  So even if you are interested in the environment, you need to know about the age structure of

  • populations.  Older householders spend, at least in the United States, India and China,

  • the three countries where it’s been studied in detail, spend more than younger households

  • measured by the age of the head on utilities services and healthcare. Utilities are the

  • most energy intensive part of the household budget.   That’s not the only reason to

  • care.  The rise in the fraction of elderly poses an increasing challenge to a relatively

  • reduced number of workers.  And it’s possible that the well-being of elderly people could

  • improve, if theyre educated or could get worse if they are warehoused in old people’s

  • homes.   We know for example, that people who are educated

  • in their youth have much lower disability when they get older.  And in fact, disability

  • rates at any given age in the United States have been dropping by about one-and-a-half

  • percent per year for the last 25 years.  So there are far fewer disabled elderly now than

  • there used to be.  That’s the meaning of 60 is the new 40, 50 is the new 30. People

  • are healthier at older ages.  That’s the result of investment in education in youth.

  •  So, there are policy implications for a rising aged population, we better invest in

  • educating people when young.   THE FUTURE OF THE WORLD’S POPULATION : URBAN

  • And the last of the four topics is cities.  And I’m going to give you a very simplified

  • and boiled down demographic history of the first half of the 21st century.  In 2000,

  • you could divide the world into two equal parts; half rural and half urban, about three

  • billion rural and three billion urban.  In 2050 the rural population will still be at

  • three billion and the urban population will have doubled from three billion to six billion.

  •  That’s a simplified history.  All of those additional three billion urban people

  • will be in poor countries.   The equivalent of a city of one million will

  • have to be built every five days from now to 2050 and all of them in poor countries.

  •  

So what’s the consequence?  What is this massive shift towards urbanization

  • mean? If we under invest in cities, we can go from

  • a billion people living in slums today to four billion people living in slums.  And

  • if we invest in the cities, if the real estate companies realize the opportunities, the incredible

  • demand that people have to live in decent housing, we could reduce the size of the slums.

  •  So, I cannot give you a deterministic picture.  I can tell you what would be awful. We could

  • have infectious diseases rampant.  We could have warfare in the cities.  We could have

  • disorder, but that’s not necessary.   We could have clean water supplies; we could

  • have security for people in their houses.  That doesn’t get as much news attention,

  • but the point I want to make is, we have choices about the future of cities and many things

  • about urbanization are positive.  And I want to tell you a few of the things that are positive.

  •  Not because theyre automatic, but because they are positive in fact and because we can

  • enhance the positive.   Compared to rural areas, urban areas have

  • lower fertility rates.  Why?  I’m a woman on the farm.  You might not think so, but

  • I amokay.  I’m a woman on the farm.  The more children I have, the more help

  • I can have in collecting the water, collecting the fire wood and tending to the goats and

  • sheep.  As soon as I move into a city, those children convert from an asset to a liability.

  •  I have to buy them clothing.  I have to send them to school.  There are school fees,

  • the apartment is too small.  The incentives completely shift direction.  Urbanization

  • makes people want to have fewer children.  

  • Cities also have higher usage of modern contraception and lower unmet needs for contraception.  Why?

  •  I am a woman; you might not know it… I don’t have to walk 15 miles to the nearest

  • health center and be exposed to the inspection of my husband’s friends when I go in for

  • contraception.  No.  When I’m in the city, I just go around the corner and it’s anonymous.

  •  So, urbanization brings many features of liberation as well as changing the incentives.

  •   Cities concentrate economic productivity.

  •  Eighty percent of the world’s gross domestic product is produced in cities, although there

  • are only 50 percent of the world’s people in cities.  Cities generate cultural assets,

  • educational resources, public health resources, medical care and they can promote energy efficiency.

  •   Let me give you an example.  This graph shows

  • the passenger transport, carbon dioxide per person. The denser the city, the lower the

  • amount of carbon dioxide per person.  New York City is reported, according to the Mayor’s

  • office, to have less than one-third the carbon dioxide emissions per person of the U.S. average.

  •  People take the subway, people ride the bus.  

  • Cities also have hazards.  Many cities are built along coastlines.  Coastlines are where

  • the continental plates of the oceans collide with the continents.  That means they are

  • prone to earthquakes.  We just had the big example in Japan, but it’s true all around

  • the world.  The Ring of Fire around the Pacific Ocean coincides with where the cities are

  • because cities are coastal.  A lot of the world’s urban people live near the coastline

  • and that’s where the subduction zones are in California.  So cities are vulnerable

  • to rising sea level, to coastal storms, cities concentrate people so theyre vulnerable

  • to infectious diseases, water supply attacks, and cities are excellent targets for military

  • and terrorist attacks, as we know in New York City and many other cities.  

  • It used to be, battles were fought on battlegrounds.  No more.  Theyre fought in cities.  And

  • that will increasingly be the case as cities concentrate assets.  

  • This is New York City as it is now.  The red zone will be underwater if the water level

  • rises by one meter on the average.  One meter is probably more than well have in the

  • next 50 years, but could easily happen by the end of this century at current rates.

  •  Now, a six meter rise would happen if the Greenland and Antarctic ice masses melted.

  •  Six meters is about 20 feet.  And that would be a catastrophe in many respects including

  • for me, there’s a little place over here in New Jersey which is my favorite nudist

  • colony. And it would be completely underwater.  So that would be a terrible thing to happen.  

  • Urban growth could affect the food supply.  Right now, cities occupy three percent of

  • the land surface of the earth.  The land, the arable land, the land where we can grow

  • food well is about 10 or 11 percent of the land surface of the earth.  It’s not surprising

  • that many cities are smack in the middle of the best arable land because that was where

  • a food surplus could be easily produced without having to ship the food.   Now, if cities

  • are going to double, we have another choice.  Do we double the area from three percent

  • to six percent and eat up our arable land, literally or do we double the density and

  • keep the areas of the cities constant at three percent. This is a choice for the future and

  • it depends on zoning and culture and real estate developers and economics and choices

  • that we make as citizens.  

CONCLUSION - FOOD: THE WORLD IS RUNNING OUT OF RESOURCES

  • TO SUPPORT ITS GROWING POPULATION How do we address the problems that we have.

  •   There are three kinds of solutions that people

  • have put forward; bigger pie, fewer forks, better manners.  The bigger pie people say

  • we should use technology to increase production.  The fewer forks people say, we should use

  • contraception to reduce population growth and we should consume less material products.

  •  And the better manners people say, we should eliminate violence, inequities between men

  • and women, inequities between rich and poor, inequities between young and old.  We should

  • eliminate rational subsidies and just make things work more efficiently.  Get rid of

  • corruption.   We need all of those and I took a few years

  • to try to figure out what’s my best way to support those three strategies, all of

  • them. And I came to the conclusion that the best response would be to educate all children,

  • boys and girls, well for 10 to 12 years, high quality, primary and secondary education.

  •  I realized there is no chance of educating people if their brains haven’t been fed

  • adequately, in utero and after birth, especially for the first three years.  

So I am

  • now moving around to working on the problem of getting food, adequate, good food, to pregnant

  • women, lactating women, and infants up to the age of three because there are many countries

  • where by the time a child gets to school, it’s too late the brain has lost its capacity

  • to learn.   It comes back to my ecological interests in

  • food.  You can’t educate without a brain that works.

  • So now were talking about food.  I started this conversation saying that there are a

  • billion hungry people, chronically hungry.  I want to come back to this.  We depend

  • on other species.  Here is a list of what other species provide to humans.  And I’m

  • going to read the list because it’s important.  Food for people, feed for our domestic animals,

  • fuel, biofuel for example, and wood to burn, biomass. And in many countries people burn

  • dung.  The waste products of animals.  That’s an important source of fuel.  Fiber, so we

  • depend on trees for many paper and other products.  Fascination, we love to go to the zoo and

  • see animals.  We love to see wildlife.  When people go out in nature, theyre thrilled

  • if they see a deer or some other kind of wildlife.  In fact, in Central Park, the German tourists

  • are thrilled to see squirrels.  We find animals fascinating.  Pharmaceuticals, most of our

  • drugs are natural products tuned up to serve human needs.  Animals provide transport,

  • they carry people places.  They provide traction, they pull plows, they pull carts.  Other

  • species provide symbioses.  I’ve talked about the animals, not the  animals, the

  • bacteria that live in our guts.  And they provide infection.  They can cause disease.

  •   So the question I want to address now is can

  • we grow enough food to bring us to 2050 without catastrophe?  These are data from the Food

  • and Agricultural Organization in Rome.  They are estimates of the number of people in the

  • world who are chronically under nourished day after day.  The current estimate is about

  • 925 million people.  That’s nearly a billion and it is higher than the number has been

  • in the last 40 years.  Ninety-eight percent of these people live in poor countries.  Not

  • only poor countries.  Here is something that shocked me and I hope it will shock you.  At

  • some point during 2009, 17.4 million U.S. households, one household in seven in the

  • United States, lacked enough money and other resources to provide food for all members

  • of the household.   The current level of food insecurity in the

  • United States is higher than it has been since the USDA started collecting the statistics

  • by sample surveys in 1995.  We are at an all time high of hunger in this country.  

  • So the question you should be asking yourself is, well aren’t we growing enough food?

  • What’s the problem?   Weve got seven billion people and there

  • are a billion of them hungry.  The answer is, less than half of the grain that we grow

  • goes into people’s mouths.  Divide the world’s grain into six equal pieces.  One

  • piece we use to make biofuels, starches, for seed and other industrial uses; plastics.

  •  Two-sixths, we feed to our domestic animals of the rich people, those who have the means

  • to afford those animals and meet products.  Less than half, the other three-sixths goes

  • directly into human mouths.  We could be feeding 11 billion, but we only feed half

  • of that amount, 5 ½ billion into human mouths.  

  • We put machines and animals in line before people who don’t have money to express demand

  • in markets.  Hunger does not fit into our economic theories.  It’s economically invisible

  • because people who are very poor, remember, half a billion are only living on $2.00 a

  • day or less.  People who are very poor can’t enter the market and plunk down their cash

  • and say, “I want that.”  They are invisible economically.  So my hunger does not affect

  • your costs for grain.  This is a problem with our economics.  And it’s a reflection

  • of our values. 

CONCLUSION - WHAT’S THE SOLUTION?  

  • So, here’s Joel’s formula for how to solve the world’s problems.  

  • Well, population; let’s go at it with all hammer and tongs.  Eliminate all unintended

  • pregnancies and educate all children to give people control over their bodies and over

  • their own lives.   Economics, open credits and markets to small

  • farmers.  A majority of the world’s farmers are women.  They are the ones out in the

  • field actually doing the work.  Eliminate perverse subsidies in rich countries make

  • it very difficult for poor farmers to enter markets because they lower the price in artificial

  • ways.  And let’s raise the incomes of the poor. 

Environment.  Use the best farm

  • lands for farms and internalize the external costs of agriculture.  Get rid of the pollution

  • and use chemicals in a way that doesn’t damage the environment.  

  • And fourth, promote healthy diets and value adequate nutrition for every person.  I would

  • add one other thing under this culture question and that is, we need to fund more research

  • in agricultural productivity for the crops that matter in poor countries.  Not only

  • for the industrial craps that fund our biofuel habit, but for the crops that provide food

  • to the poor.   CONCLUSION - SUMMATION

When you walk

  • away from this conversation, I hope that youll remember that population interacts with economics,

  • the environment and culture so that you immunize yourself against people who will try to sell

  • you an overly simple bill of goods.  And there are a lot of people.  There are people

  • who say, “Demography is destiny,” and all we have to do is get a contraceptive in

  • every pot and well solve the world’s problems.  That’s wrong.  

  • And there are people who say all we have to do is get the market right.  Let the market

  • take care of all the prices.  In my view, that is equally wrong and much more dangerous.

  •  There are people who say, “It’s only a matter of law and getting the laws right.”

  •  Yeah, but it’s also a matter of technology and contraception and economics.  And there

  • are people who say, “Forget about the people, let’s just save the environment.”  I

  • don’t believe that because I’m a human being and I value other human beings.  Weve

  • got to get all of these things working together and the environment can be on the side of

  • human well being because poor rural people depend directly on the environment for their

  • sustenance.  If they want to have a sustainable sustenance, they have to have a sustainable

  • environment.  

Demography makes it possible to imagine and to re-imagine the future.  

  • I’d encourage any freshman, sophomore, junior, senior, adult, high school student—I’m

  • not age prejudicedanybody who wants to do three things to consider demography.  It’s

  • not the only field that offers these attractions but it does offer them in spades.  It’s

  • really very attractive.  First of all, demography gives you tools and analytical perspectives

  • to understand better the world around you.  That’s understanding.  

Secondly,

  • it gives you equipment to solve problems mentally.  It’s mentally exciting; you really have

  • to use your noggin, and if youve got one use it or lose it.  So it’s use it.  And

  • third, it is the means to intervene more wisely and more effectively in the real world to

  • improve the wellbeing, not only of yourselfimportant as that may bebut of people around you

  • and of other species with whom we share the planet.  

So it prepares you to go out

  • and do something that’s worth doing for a larger good than only yourself.  So there’s

  • an old saying, “If I am not for myself who will be; but if I am only for myself what

  • am I; and if not now, when”?  So now is the time.  Pull up your pants and get to

  • work.

Thank you. 

My name is Joel Cohen I’m Professor of Populations at the Rockefeller

字幕と単語

ワンタップで英和辞典検索 単語をクリックすると、意味が表示されます

B1 中級

Joel Cohen: An Introduction to Demography (Malthus Miffed: Are People the Problem?)

  • 630 29
    Furong Lai に公開 2012 年 12 月 07 日
動画の中の単語