CENSUS AND SENSIBILITY: Population and Resources

Wednesday, October 21, 1998

Two thousand years ago, the Earth had about 250 million people. Today it has six billion people. Is six billion too many for Planet Earth? Gretchen Daily, Research Scientist, Center for Conservation Biology, Stanford University, Tom McMahon, Executive Director, Californians for Population Stabilization, and Stephen Moore, Visiting Scholar, Hoover Institution, Director of Fiscal Policy Studies, Cato Institute discuss whether our resources are being depleted beyond sustainable limits, or will human ingenuity continue to support an expanding population.

Recorded on Wednesday, October 21, 1998

ROBINSON Welcome to Uncommon Knowledge. I'm Peter Robinson inside our very own biosphere. Our show today: Population. (I'll get back to the biosphere in a moment.)

Two hundred years ago, Thomas Malthus predicted that the human population would grow very dramatically, outstripping any growth in food supplies, and ending in starvation. So far, Malthus has been half right-- human population has grown dramatically— but also half wrong. By and large the growth in food and other resources has kept pace with the growth in population. But, will resources continue to keep pace?

With us today, three guests. Stephen Moore of the Cato Institute believes a very large population is no serious problem. Tom McMahon, executive director of Californians for Population Stabilization, and Gretchen Daily of Stanford University's Center for Conservation Biology, disagree. Which brings us back to the biosphere. In the early 1990's, scientists in Arizona built the real biosphere. It was a kind of huge greenhouse: oxygen inside, plants, animals, and people— a kind of modern day Noah's Ark. The idea was that if they could replicate the conditions that would sustain human life in the middle of Arizona, one day they might be able to do the same on Mars.

The biosphere was a bust. Oxygen levels dropped, the human beings inside had to be gotten out, and nearly all the plants and animals ended up dead, with the exception of cockroaches and ants. The moral for population? Depends on your point of view. One moral might be that Earth's environment is so delicate and so complicated that at a population of six billion and growing, human beings do indeed pose a threat to the very natural resources on which we all depend. The other moral might be that scientists, from Thomas Malthus to the scientists who built the biosphere, don't always know what they're talking about.


ROBINSON Two thousand years ago, the Earth had about two hundred fifty million people, and today it has about six billion people. Is six billion people too many people for planet Earth, Tom?

MCMAHON Absolutely.

ROBINSON How come?

MCMAHON We're overpopulated because we're destroying the ecology of the life-support system of the human race.


MOORE There are too many people in the world who think there are too many people in the world. The fact of the matter is that the human condition has never been better. People are richer and better fed than any time before in history.

ROBINSON Gretchen— six billion too many?

DAILY Both of those answers are correct. The key issue, though, is: Are we living sustainably? Are we leaving a bright future for our children? And the answer to that is no. We're using up the capital upon which all of the economic activities we engage in depend. Our natural capital that supports us is being depleted. Therefore, people are worried that we won't be able to sustain the wonderful increases in well-being that we've had, and worry that yeah, even six billion might be too many if we can't as a species get our act together.

ROBINSON Okay, so that's kind of a nuanced argument. You admit that there've been tremendous advances in standards of living for... large numbers of people. But we can't keep it up.

DAILY Oh sure. We're living like... Even under the most optimistic scenarios we're going to get up to at least eight billion people before stabilizing. More likely, the medium UN projections are that we'll get up to ten billion or so. But what are we doing to our life-support systems? That's the question. We're basically, we've got a bank account and we're running down the capital, and we're bragging about it.

MCMAHON So we're over sustainability right now as we speak.

DAILY Right. We've crossed many of Earth's limits.

ROBINSON Let's run through the things that we need to sustain large numbers of people. The obvious item is food. We're producing enough food right now?

MOORE The problem is, probably too much food. I work in Washington where every year we give away billions of dollars to farmers so they won't grow so much food because we have such a capacity. I mean, you look at just three or four states in the United States— Iowa, Missouri, Illinois, Kansas— they could virtually feed the entire world, that's how productive our farming sector is.

MCMAHON That's definitely not true.

MOORE It is.

(several voices)

ROBINSON Let Tom make his point.

MCMAHON I mean, that is not true at all. World-Watch Institute has done studies now showing that we've just about reached the maximum capacity of the potential for energy to be converted into food.

DAILY He meant you could judge humanity's success in feeding itself by two criteria, okay: one criterion would be, well, How many people actually have food in their bellies and how many don't. The second criterion would be, Are we doing this in a sustainable manner, okay. If you look at the first point, people are better fed than they have been in the past, although eight hundred million people remain malnourished— they don't get enough calories much less a balanced diet to sustain normal daily activities.

ROBINSON Go ahead, Steve.

MOORE Let me make a couple of points on that. First, you know, you said, How do we measure whether people are better fed, and whether we're able to feed ourselves. And I think one of the best ways of measuring whether we're able to feed ourselves is whether people can afford food, whether food is affordable. And what we're finding is that the price of food in the United States and all over the world has plummeted relative to people's incomes. People are spending a lower percentage of their incomes on food now than ever before. And why is that happening? Mainly because of just huge technological progress in the agricultural area. And I believe that agricultural progress will very dramatically continue in the future.

MCMAHON That's a totally specious argument. The price of something isn't necessarily a good indicator of the sustainability of that resource. For example, take fish. The price of fish has not gone up that much, because the technology has allowed us to catch more and more fish. Except, we've driven so many species into extinction now, and the supply is level, so that we cannot increase the consumption of fish in the world today because the fisheries have reached their sustainable level, or below sustainable level...

ROBINSON Steve says food is getting cheaper, but Tom says prices don't always reflect scarcity. What can the market tell us about this problem?


ROBINSON Stephen is making a kind of market point, which is that the market is responding to the growth in population, and as a matter of fact it's keeping ahead of the growth in population as regards food, and the indicator for that is prices. If the price of something drops, you've got plenty of it. Now, Tom makes the counter-argument that in the matter of fact, at least one large source of food comes from areas that are effectively outside the price mechanisms of the market. Fish in the ocean are free to any fisherman who has the ship to go scoop them out of the ocean. How do you answer that?

MOORE That's a classic tragedy-of-the-commons problem that you have over fishing going on in the oceans, where you have private fisheries— actually fish catches— are substantially up. But we ought to realize, though, that one of the reasons that the population has grown so dramatically over the last two centuries has been— well, there's really two explanations for this Peter. First, we see incredible improvement in terms of reducing infant mortality, not just in this country but around the world. And the second reason we see this vast increase in population is people are living longer. We have dramatically increased the expansion of life so that, for example, in 1900 in the United States, the average person lived to 50; today life expectancy is up to 75. These are human triumphs. We should be actually celebrating the fact that the population is growing because it's a reflection of the fact that we're overcoming death.

ROBINSON Well, I'm willing to celebrate the fact that my own kids are healthy, and that I myself will live a long time, but as a logical matter I can still feel quite justified in worrying that we're using up the resources at too fast a rate.

DAILY The key issue is, Can we sustain what we're doing, or are we just, you know, race to the bottom. And that is the key problem. We've brought about these improvements at a huge cost. Three key elements of our capital include our deep, rich agricultural soils, our fresh water, and our biodiversity— the natural ecosystems that supply us with our basic life-support functions. They purify our water, they clean our air, they regenerate soil fertility— only part of that done by adding fertilizers— they provide fish in the oceans and all these other things. Each of these are being run down and degraded like never before. We're losing each year an estimated twenty-five billion metric tons of topsoil a year. That's the amount...

ROBINSON Who's we— the world or the United States?

DAILY The U.S. And that's the amount that used to underlay all of Australia's wheatlands.

ROBINSON Yeah, go ahead Tom.

MCMAHON This ecological footprint analysis, this is a process that was developed in Canada, and it's been developed over the last thirty years. And right now the world is 37% under sustainability. We would need 37% more land surface of planet Earth to sustain the people that we have now in the world at the level that they're living at.

ROBINSON When do people start dying? When does the starvation kick in?

MCMAHON It's beginning in certain places in Africa. When we reach a point where the soil washes out, then we have to move some place else. And there are places in the United States right now, because we've run down the water table, that the agriculture is out of production.

ROBINSON There have been doomsayers about human population at least since Malthus two centuries ago. And so far, the doomsayers have been wrong. What's different now?


ROBINSON There's almost a kind of theological or psychological overlay to your predictions of the future. For one reason or another, you look at the future and you see doom, whereas if you were to be informed by the actual record, the actual human record, and particularly the human record of the last fifty years, when the population has a little bit better than doubled, but at the same time we've seen living standards rise to higher levels than ever before in human history, the actual record is astonishing. And so...

DAILY Let me give you an answer to that.

ROBINSON Go ahead.

DAILY I've got here with me a statement that was published, it was signed by the vast majority of the living Nobel laureates in the sciences, including in economics. And just to read a little bit from this statement, to tell you what the facts are, but it's so difficult to get this out in the media and into discussion because this has become a polarized political debate. But within the scientific arena there is no debate over these basic things. They say, for instance, "Pressures resulting from unrestrained population growth put demands on the natural world that can overwhelm any efforts to achieve a sustainable future. If we are to halt the destruction of our environment, we must accept limits to that growth."

ROBINSON And if you believe all of this very deeply, as both of you clearly do, you actually have a responsibility to persuade ordinary folks. There is a deep strain in this country of suspicion of elites and experts, and I have to say that throughout the period of the Cold War, scientists seem only too eager to sign petitions calling for bans on nuclear weapons, or this, or, I mean, this is kind of an old, we've seen this. So, my question to you would be...

DAILY You're being inconsistent here.

ROBINSON Go ahead.

DAILY You're saying that , Well, we've made all these great improvements and they're because of our incredible scientific ingenuity, and because of our fantastic scientific enterprise that we've been able to do what we've done, and that we'll be able to continue. And what's happening now is that the leaders of this enterprise, the people that are on the cutting edge...

(several voices)

ROBINSON (amid the hubbub) It's not Nobel Prize winners who gave us free markets...

DAILY Oh, but of course it is...

MOORE Let me respond to Gretchen's point. This is the same claptrap that we've been hearing for the last forty years. In fact, it was just twenty years ago that the Global 2000 Report came out, that the Club of Rome Report came out, and they all predicted, and many of these very same scientists Peter who've been wrong for twenty years. They said, for example, twenty years ago, Gretchen, that the price of oil would be a hundred dollars a barrel...

DAILY (above several voices) You just missed the point that we brought up before, that prices do not reflect what is going on... Any economist can explain that to you.

MOORE If something is getting cheaper, how can we be running out of it? That makes no sense.

DAILY If it's not captured by the market.

MOORE It is being captured... In fact...

DAILY There are an infinite number of cases where markets don't work perfectly. Any economist can explain that.

MCMAHON It's very unfortunate that certain scientists in the past have become neo- Nostradomuses and tried to put a date on when things would happen. And that is a disingenuous thing. Nobody has the wisdom and the complexity of Earth's ecosystem to put a date on when certain things will happen.

MOORE Well then, how can we ever prove them wrong if they never...

(several voices)

MCMAHON I told you about the fisheries, which is a very dramatic example because most people think that, you know, the ocean is larger than the land area and that this is like an infinite resource. Well, it certainly isn't.

ROBINSON After issuing one dire warning after another, Tom is refusing to make predictions. How come?


ROBINSON It's a hallmark of science and of the scientific method, that is experimentation, right. You make a prediction and you test it. It has to be objectifiable, it also has to be capable of being proven false. So I would think that there ought to be modest, modest predictions that ought to be proven...

DAILY We haven't been talking about predictions. We're talking about the state of the world today. These are measurable changes. We have very carefully documented the extent to which humans are impacting and degrading the land surface. We have very carefully documented how much water we're using and how much more there is...

ROBINSON ‘Impacting and degrading.' ‘Impacting': okay. But ‘degrading' already is a value judgement, isn't it?

DAILY We're talking about big issues: how much productive land we've got on Earth, and how much of that is being run down because of human activities and poor management. And this sort of thing is well-documented. We've also well-documented how much fresh water there is available. This is another case where you look at, like, from outer-space, you look at Earth and think, My gosh, it's a water planet, how could we possibly run out of fresh water. And yet, it's incredible, well, it's obvious at a local scale to any Californian that we're running up against limits in drier regions. At a global scale, humanity is already using over half of the renewable fresh water supply.

MOORE A larger percentage of the people in the world today have access to clean water than ever before.

(simultaneous voices)

DAILY Not true. That's not fair. The World Bank... The United Nations... I don't know where he's getting this...

MOORE It used to be, fifty years ago, that we didn't even have access to modern sewage, or modern... It used to be, a hundred years ago, nobody even had sewage systems...

MCMAHON Lots of Americans don't even have access to clean water, I mean...

MCMAHON Wait, wait. You're talking about two different things. There's different ways of polluting water. One of them is with bacteria. We know how to get rid of the bacteria. (several voices) But when you put into the water hydrocarbons that are carcinogenic, it's very difficult to get them out.

MOORE If everybody had access to worse and worse water, then we wouldn't have people living longer and so forth, people would be dying of the kinds of diseases that they did fifty years ago that we have wiped off the Earth.

ROBINSON It's a central part of your argument that there is so much fresh water only, that that's a fixed resource?

DAILY Well, you would agree with that, right? It's not coming in from outer space.

ROBINSON No, no, I'm absolutely certain... Hold on, hold on, let me make a point. Resources, in a certain sense, are not finite. Oil wasn't a resource until human ingenuity created a purpose for it. [DAILY Right. That's why I'm bringing up water.] Sand wasn't a resource until human ingenuity created the silicon chip, and now, okay. So my question would be...

DAILY Right. But water, there's no substitute for water in most of its important uses.

ROBINSON Fine, but how can you so confidently say that the resource is so tightly limited?

DAILY I'm saying today we are already using over fifty percent of accessible fresh water. Most people in the world don't have as much access to fresh water as they would like. Most of us, we would never trade our lives voluntarily for the lives that the vast majority of people on this planet live. Two-thirds of the people on this planet earn less than three dollars a day. Twenty percent earn only a dollar a day or less. We'd never trade our lives for that, so if you consider how inequitable the distribution of water is today, the projections of population growth, we're likely to be using all, in theory, of Earth's accessible fresh water within the next two decades.

ROBINSON This is your last comment on water.

MOORE Gretchen and Tom seem to see people as people who use resources. People also are producers of resources. I am going to leave, hopefully, the world better off in terms of resources. We are creators of resources.

DAILY What I'm saying is that we've paid a price to get to the place where we are today, and that should give us pause. We ought to stop and think, Well, how much did we pay to get where we are today. We've paid a lot in terms of what we're leaving to future generations.

ROBINSON We've discussed two of Gretchen's key elements. Now for the third: biodiversity.


ROBINSON What does biodiversity mean?

DAILY Okay, it means the variety of life that we've got on the planet. Then you've got to ask the question, "Why should we care about this variety of life anyway?"

ROBINSON I do, but you go ahead and interrogate yourself.

DAILY Okay, I'll interrogate myself, and offer good examples. Just imagine, one way to look at it is to say, imagine that you, one year from today, were going to get on a spaceship on a one way trip to the moon. You'd have to ask yourself, what are you going to bring with you, maybe after convincing a few friends, packing a barbeque, and so on. You'd have to get to the question, What am I going to eat up there. Let's assume you're not going to die the minute you get out of the spaceship. Let's assume it has an atmosphere and a climate similar to what we have on Earth, even though we know that life plays a critical role in determining these here. We'd have to start thinking, Okay, well, what do we eat. There's a huge variety of crops. You know, what you ate for breakfast, what's in your junk food, those are all species in there. You start making a list of which organisms we use directly. But then you'd have to get to the basic question: How are you going to support those. Most of our crops, for instance, are pollinated by other animals, little bees and other things that fly around.

ROBINSON So we've got to eat, the cow needs corn to eat, the bees need to get...

DAILY ...The corn needs soil, the soil has...

ROBINSON ....needs earthworms...

DAILY Yeah, and many other kinds of things, right. You'd need all these systems...

ROBINSON ...to break down the little bacteria...

DAILY Right.

ROBINSON So biodiversity is the vast interconnectedness and complexity of systems of life.

DAILY Right. It is our life-support system. And we know not nearly enough about, you know, how many species are required to sustain life. We do know it's a huge number. In Biosphere II, for instance, remember that facility they developed in Arizona, this three-acre area [ROBINSON Under a bubble.] that cost of two hundred million dollars and they stuck eight people inside. Things became a disaster overnight in there. The oxygen levels plummeted to what you find at above 17,500 feet...

MCMAHON They had to pump oxygen in because the people...

DAILY ...yeah. Carbon dioxide went way up. People were being asphyxiated. Nitrous oxide, another gas that's regulated by soil organisms, got to concentrations that impaired brain function. The bottom line here is that we have no technological alternative to supplying these services on the scale required.

MCMAHON Where we are getting into difficulty is, that the economic system that the world has today, for the most part, does not take into account all the things that nature does, and they don't put a price on it.

ROBINSON So the farmer gets the bees pollinating his crops for free. I don't mean to make a trivial example, but there's a great deal...

DAILY That's a perfect example.

MCMAHON That's a good... that's funny... that's one very good example. And the microbes in the soil are the ones that are eating the corn husks and things and turning it into soil, and if we poison those microbes, then that's not going to happen. We have to substitute something else for it.

ROBINSON That which human beings do not profit from, they don't protect and preserve and cherish, would that sort of be...

DAILY Well, it's outside the market...

MCMAHON No. It's not included in the cost of producing the food, see. In other words, when you dump pollutants into the ocean, nobody pays for that.


MOORE They should. People should pay if they pollute the ocean.

ROBINSON Do I detect a momentary point of contact between all three arguments here?

MOORE If a person pollutes my property or the ocean they should have to pay for it.

MCMAHON Most industry today does not take that into consideration. And the price would be much...

MOORE O.K. And if they don't pay for it, they should. I think we all agree on that.

ROBINSON You do accept the argument that the price structure and the system of property rights misses important things.

MOORE Oh, there's no question about it.

ROBINSON And people who are environmentally sensitive may in fact awaken sensitivities in all of us that we need to expand the system of price structures and property rights so that it covers... (several voices) Pursue that theme for a moment.

MOORE Well, the area where we're losing the most resources are in publically held lands, you know. Why are we losing forests in Brazil, for example. Because those are lands that are owned by the government, and so no-one has an incentive to protect them.

ROBINSON Technology has fueled population growth. Will there be political developments that place a limit on it?


ROBINSON He's been talking about the possibility of technological innovation, but there exists also the possibility for political innovation as well, right? So things could work out.

DAILY Right. The basic thing, we're at a situation... we're in an unprecedented situation. Let me just give you a quick perspective, okay.

ROBINSON Oh no, scary stuff again. Okay, go ahead, go ahead.

DAILY Let's look at the situation. We have— like you started out, okay, and then you stopped, you started out— we had two hundred and fifty million people at the time of Christ [ROBINSON Right.]. We grew over, it was most of human history until we got to about one billion people in 1850. Then in eighty years we added the next billion, in thirty years we added the third billion, in a mere fifteen years we added the fourth billion, in a mere twelve years we added the fifth billion while I was an undergraduate, and in a mere eleven-and-a-half years we added the sixth billion...

MOORE (over DAILY) We keep getting richer and richer and richer. It's the most amazing time.

MCMAHON What's interesting is, he keeps saying people are getting richer and richer. And I spent thirty years of my life living in undeveloped countries, and I can tell you...

MOORE Thirty years ago.

MCMAHON No, no, I was just down in the Amazon last summer, and I go to where the problem is. And I can tell you that the people are not richer. The people in Mexico...

(several voices)

ROBINSON In Mexico, you named Mexico, after World War Two, Mexico had one of the highest birth rates in the world [MOORE That's right.]. And today, Mexico is right about in the middle, and the birth rate per woman in Mexico is about three and dropping. So things are okay maybe, right?

DAILY ...It's really interesting on the population front. Twenty years ago people thought, My gosh, how are we ever going to bring this tremendous growth that I was just describing to a humane halt, you know, as opposed to having disease, famine, war and other things come in and halt things for us. And yet we've made tremendous progress on the population front. (several voices)

MOORE Now for years and years people thought the way to get economic development is to control population growth. And it turns out they had it absolutely backwards. The truth is that when people get richer and they have more income, birth rates start to come down, and that's what's happened in virtually every developed country in the world.

ROBINSON Should we promote free markets around the world, and economic growth, to bring birth rates down?

MCMAHON Only if the economists will bring in the ecological aspects of it. And that is, what the Earth is doing to absorb all the pollutants that industry is creating. They're not putting a price on that, and that's the major problem...

ROBINSON Okay, but Moore is willing to do that.

MOORE The areas in the world where you see the most ecological harm done, and the greatest ecological disasters, are poor countries. In fact, you've got a lot of the countries in the Third World that— they don't have to worry about things like biological diversity and global warming, they have to worry about whether they have clean water, whether they have sewage systems, and so on. And the solution to this is economic growth, is a free market system, because that will solve a lot of these ecological problems.

ROBINSON Predictions, predictions, predictions. You don't want the crystal ball, but it's TV and the crystal ball is part of this show. Predictions. We've named a number and we've named a horrible condition. The number is eight hundred million and the horrible condition is malnutrition. Ten years from now, as the population grows, will that number of people who are malnourished, eight hundred million, be higher or lower? Tom.

MCMAHON I don't make predictions, but what I would like to say is that probably a lot of them will be dead.

ROBINSON No, but I mean, ten years from now will there be eight hundred million people malnourished, or will economic growth have gone...

MCMAHON I'm not going to be a neo-Nostradamus and put a time frame on it.

ROBINSON Okay, now you won't play that game either?


MOORE They won't make predictions because all the predictions that the doomsayers have made for the last fifty years have been wrong. But the reason that there'll be fewer people, percentage-wise, who are malnourished in the future...

DAILY Percentage-wise. Let's talk about that.

MOORE Right, no, okay, well an absolute number, if there are more people then there may be more people malnourished...

DAILY There we go.

MOORE ... but the point is that in percentage terms, more people will be moving out of poverty and a larger percentage of people will not face the problem of malnourishment or hunger.

ROBINSON Because of...

MOORE Because food capacity is rising and because people are going to be richer and their capacity to buy food increases.

DAILY What Tom and I are saying...

ROBINSON Gretchen, Steve, and Tom: thank you very much.

ROBINSON So what we seem to have is a race between human population growth and human ingenuity. Two of our guests, Tom and Gretchen, put their money, so to speak, on population growth with, they expect, dire results. Our other guest, Steve Moore, puts his money on human ingenuity, with much happier results. Needless to say, I hope that Steve is correct, although if the Biosphere is any indication, and the oxygen level seems to dropping right here inside our own biosphere [giant blowing sound], we have some work to do. I'm Peter Robinson. Thanks for joining us.

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