About the author of this backgrounder: Dermot Grenham is an actuary for the Prudential Assurance Company in London.


Demography is a science that deals with people, their past, present and
their future. It is easy to get lost in the volume of statistics that
is available and lose sight of the individual by concentrating on the
crowd. Demographers must never forget that their subject deals with
real people with real life stories. They are not just numbers.

The purpose of demography, if it is to be true to its calling as a
science, is to provide knowledge about the human condition which will
help to improve the lot of the current and, perhaps more importantly,
future generations.

This paper sets out to summarise the current position on those issues
that deal most directly with the issue of population numbers. It will
cover topics such as energy and other natural resources, water, food,
land and the environment. This paper also covers a further topic that
is becoming increasingly more important namely the ageing populations
found in the developed and a number of developing countries. Whole
books could and have been written about each of these topics so this
paper will do no more than skim the surface. The references and
bibliography will provide sources for further research.

Until relatively recently the population control lobby seemed to be
having the best of the argument, if not in theory at least in practice.
However, over the past decade most of the debate has swung around. The
main arguments of the population control lobby now focus on the impact,
the demographic footprint, of humanity on the environment.

This paper puts forward the counter arguments to those who would want

to control the size of the population through means which people would
consider immoral such as forced sterilisation and abortion, linking aid
to the acceptance and usage of contraception, imbalanced government

How many is too many?

In any discussion about population one sooner or later gets on to the
question as to whether there are, or soon will be, too many people in
the world. However, this question has to be asked in the context of
what one means by too many and also linked to the question of what
would be too few. There may be some who would be quite happy for the
human race to die out but the process required to get there would be
extremely painful for those caught up in it. I will therefore take for
granted that the readers of this paper wish to see the human race
continue and flourish even if they have concerns over the impact that
we are having on the environment.

One’s view of how many is too many can easily be coloured by, for
example where one is currently living. Living in the South East of
England or Chicago can given one the impression that there is no more
room left. However, living in Scotland or Idaho gives the impression of
there being plenty of room.

Similarly, the level of attachment to one’s current standard of living
can make one afraid of a potential drop in this if the number of people
in the world continues to increase. However if one is happy for
economic well being to be more widely spread, especially if one
believes that this would lead eventually to everyone being better off,
would tend to make one more relaxed or even very keen on further
population growth.

No discussion about population takes place in an ethical vacuum.
Everyone brings their own beliefs, prejudices, fears and hopes to the

Generally one’s views about the effects of population growth are
consistent with one’s views about the ability of the human race to deal
with the problems that population growth could bring with it. If one
holds that each child not only brings a mouth to be fed but also a
brain and two hands with which to work, one will tend to take a more
optimistic view of population growth and see any problems that it may
bring as localised, short term or due to other factors.

In discussions about the effects of population growth it is easy to end
up trading anecdotes, on both sides, showing the benefits or the
drawbacks. What one has to do is to look at the available evidence, as
both Julian Simon (see for example Simon (1996))and Bjorn Lomborg
(Lomborg 2001) have done, with a dispassionate eye. One also needs to
look at long term trends rather than transitory situations.

Some demographic theory

The current (2005) population of the world is around 6.5 billion people
(United Nations Population Division 2004). The population is projected
to increase over the next 50 years to around 9.1 billion (United
Nations Population Division 2004). The current population projections
are below projected numbers that had been produced in the previous 5 to
10 years, and could themselves be over-estimates of what the size of
the global population in 2050 will be. This does not mean that there is
an inherent bias in the projections, just that projecting the size of
any population, let alone that of the whole world is notoriously
difficult. Key factors which have caused the over projection have been
assuming higher fertility rates than have actually occurred and not
allowing sufficiently for the impact of AIDS/HIV.

Although all those that will be over 50 years of age in 2050 are
already born, the key determinants of the population will be the
fertility and death rates and, at a national level, the levels of
immigration and emigration.

Over the past at least 100 years, death rates have been falling in most
countries such that life expectancy at birth has increased dramatically
around the world. (Russia is a notorious exception in Europe.) This
would have happened nearly everywhere except for the impact that HIV
AIDS is having, particularly, in a number of African countries.

At the same time fertility rates (the number of children that each
woman, on average, has) have fallen in all countries. The fall in
fertility rates has generally happened later and more slowly than the
fall in death rates which is why the population has increased
significantly in many countries.

In all developed countries the fertility rate is below the so-called
replacement ration which for most countries is around 2.1 children per
woman. The 0.1 is there not so much to make up for those who do not
reach childbearing age but to make up for there usually being more male
than female babies born. In an increasing number of countries the
fertility rate is so far below the replacement ratio that it is
becoming a major national concern.

Will we run out of space?

It used to be said that the population of the world could all fit,
standing up, on the Isle of Man, a small island in the Irish Sea
between Britain and Ireland. Although this may not be true, it is
certainly true that the population of the world could fit into to the
UK. It might not be a comfortable experience but it does give an idea
of how small the human population is in comparison to the size of
planet Earth. By bringing everyone to the UK one would also be leaving
the rest of the planet devoid of humans.

The problem with land, though, is not really that there may not be
enough of it but rather that there is not enough of it in the places
that we want it to be. There is not enough room, for example, in the
South East of England especially as more and more people from the rest
of the UK and abroad are attracted to this location. But this is not
bad news for everyone; those that currently own property in this area
are seeing the value of these increasing dramatically.

It is unlikely therefore that human beings will ever be too numerous
that there will no longer be room on plant Earth. Even if we were one
day to run out of room it will take so long to get to this stage that
we will have discovered how to colonise space.

Will we be able to feed ourselves?

The ability of the human race to feed its increasing numbers has been
the consistent worry of those concerned about population growth. (Of
course, the population has not always been increasing. During the
Middle Ages in Europe, for example, the population was decimated by
bubonic plague.)

Thomas Malthus (Malthus 1803) is perhaps the best known advocate of the
argument that while populations grow geometrically, food production
only grows arithmetically. Fortunately, experience has proved Malthus
and the more modern day followers of his train of thought, such as Paul
Ehrlich (Ehrlich 1968), that food production not only can keep pace
with the growth in population but can also outstrip it.

The introduction of new technologies in food production, for example,
Asia’s Green Revolution, of the means that more people can be fed on
the same or even less land. And there is no reason to think that new
developments will not continue to happen.

Even before the Green Revolution got into full swing, Colin Clark
(Clark 1967), director of the Agricultural Economic Institute at Oxford
University had shown that the world, using the then best agricultural
practices could support, on an American diet, a population many times
even the current level.

Those against population growth will argue that the amount of land
being dedicated to agriculture is decreasing and the existing stock of
farm land is being worn away by overuse. Not only is it not proven that
the amount of farm land is decreasing, but even if it was, as long as
we continue to make our farming more efficient, the reduction in farm
land should not be a cause for concern. Land degradation would be a
worry but again the re is no proof that this is happening to any
significant extent.

The situation can be summed by quoting from Mitchell and Ingco’s

Executive Summary to the World Food Outlook published by the
International Economics Department of the World Bank in November 1993
(Mitchell 1993): “Periodic food shortages caused by weather
disturbances will still occur, but the problem of inadequate world food
production over extended periods seems to be past.”

Will we run out of energy?

It may all be very well to have plenty of land and, as we shall see
later, lots of other things, but if we do not have energy then this
will be no use. Are we then in danger of using up our energy resources
and being left having to light fires with flints and sticks?

Given that the primary source of most of our energy is the Sun, which
is expected to be around for millions of years yet, there is no reason
why we will run out. The question is how we can harness this energy.
The Earth has provided us with ready made sources such as oil, gas and
coal and the goal is now to develop other sources while these last,
which according to most estimates will still give us a lot of research
time. From time to time there are scares about reserves running out but
this is usually because the energy companies have simply not looked any
further because economic conditions do not warrant it. If energy prices
increase then it makes more sense to look, say, for oil in more
difficult places and technology is developing which makes this easier.

Also, the sun is not the only source of energy. There are renewable
sources such as wind and wave power. Also there is nuclear energy
which, as long as it is safe, and there is no reason why it should not
be, can provide plenty of energy. Scientists continue to look for the
holy grail of cold fusion which will provide an almost unlimited source
of cheap and safe energy.

Other resources

What about the other resources that we need to live a civilised life: copper, aluminium, iron and so on?

The best answer to this is to describe the bet that Julian Simon made
with Paul Erhlich in 1970 (Simon 1996). Simon offered Ehrlich a bet
that over a ten year period any five metals, to be chosen by Ehrlich,
would become cheaper rather than dearer, thus indicating that they had
become either more plentiful or less necessary. Ehrlich chose copper,
chrome, nickel, tin and tungsten. When the bet came to be settled, the
price of each of these metals was lower in absolute and not just in
real (i.e. allowing for the effects of inflation) terms.

Simon considered the bet to be easy money because throughout history
this has been what has happened. Resources have been getting cheaper
and cheaper. This is because new ways have been found to extract them,
including recycling, or they have been replaced by better alternatives
egg glass fibres replacing copper in certain parts of the
telecommunication system.

Natural resources are not infinite in the sense that there is an
infinite amount of them but they are infinite in the sense that we will
never use them up, as they appear to get scarcer, human ingenuity,
inspired by the profit motive, finds new ways of getting at them or
making do fine without them.

Will we run out of water?

There have been plenty of scare stories about the next wars being fought over water, especially in the Middle East.

Fortunately, the amount of water available is huge although not always
directly available to drink. To create the right type of water for
drinking, farming and industry requires energy, for example for
desalination plants, which as outlined above is unlikely to run out.

Part of the improvement in agricultural technology was the more
efficient usage of water in irrigation which means that less water is
required to grow the same amount of crops.

Economic growth

Many people feel that more people would at least slow down the rate of
economic growth. The evidence, though, does not back this up. There is
no direct connection between economic growth and population growth. A
more important factor than population growth appears to be the economic
and political structure of the country.

It is not so far fetched to argue that population growth is good for
the economy because for any economy to grow it needs to have consumers
of its products and as the pool of consumers grows so too do the
opportunities for economies of scale. At some point one may hit
declining returns to scale but this where new technologies, products
and markets will be introduced.

The environment

The topic upon which the population control lobby are pinning most of
their hopes now is the impact that the human race is having on the
environment already and how a larger population will necessarily have
an even bigger impact. Whether such arguments worry you or not depends
on your view of the ability of human beings to solve the problems we

Much has been made of the potential impact that global warming will
have on our Earth. One though needs to treat projections of the effects
of global warming with a healthy dose of scepticism.  Modelling
the effects of climate change on the world’s weather systems makes
projecting populations look like child’s play. Most weather forecasters
struggle to predict the weather in a week’s time so how can we rely on
much longer term predictions?

But is it not better to be safe than sorry?

Yes, but at what cost? This
is where we come up against the problem of what is the key resource
shortage, human beings. We simply cannot do everything and therefore
have to decide how to use our resources most effectively. Do we want to
build defences against an asteroid hitting the earth or implement
measure to reduce carbon dioxide measures or use the money that this
will cost to provide solutions to local water shortages and eradicate
malaria? Bjorn Lomborg in his book The Skeptical Environmentalist
(Lomborg 2001) has shown that as well as the climate change lobby
basing their arguments on potentially faulty data and models, even if
these were flawless, climate change is not necessarily the main problem
affecting the planet. It just seems to be the one highest up the
political agenda.

A future with too few people?

So much for the arguments for and against population growth. What is
causing more concern, especially in the developed countries is
the effects of below replacement fertility on their economies. The fact
that developed countries have to focus on their potentially declining
populations may be one of the reasons why the anti-population growth
rhetoric has become more muted in recent years, although on the ground
there are still plenty of governments and agencies promoting population
control policies.

As an example, the First Minister of Scotland said on 25 February 2004:
“Scotland’s population is falling. It is declining at a faster rate
than anywhere else in Europe. And this decline, coupled with a
significant shift in Scotland’s age profile is making a serious problem
even worse.”

Where most developing and an increasing number of developing countries
are is in the early stages of natural population decline i.e. fewer
births than deaths. Italy and Spain are two countries in which this is
happening. This may not seem like too big a deal especially if one is
still worried about global over-population. However, although a decline
of the odd couple of million here and there may not be too big a cause
for concern, what is more worrying is if the current trend continues.
In her book Son of Man the novelist P.D. James imagines the terrifying
consequences of a sudden complete halt to new births all over the
world. This is more extreme than the world is likely to face, but at
some point there would actually be too few people to maintain social

The UN projects the population of the current Europe to fall from 728
million in 2005 to 653 million in 2050. On the other hand North America
is projected to grow from 331 million to 438 million over the same
period (United Nations Population Division 2004). If competition
against the USA is hard enough at present what is it going to be like
as Europe gets even older and greyer compared to America. Where are the
entrepreneurs, the risk takers and the creative spirits more likely to
come from? Those of us of a certain age may not really care as we will
be out of here before the declining population has any major effect, or
at least we hope so. However, if the current inhabitants are the
trustees of the earth on behalf of future generations this trusteeship
should also apply to maintaining human society and not only the natural

David Willetts (Willetts 2003) points out that the UK citizens should
not be too smug in the face of our continental European neighbours when
considering provision for our future retirement. The general opinion in
and of the UK is that we are safe with our funded pensions schemes
while the continent is heading for trouble. If HMS Europe is sinking
under the weight of its aging population although we may have brought
our own life jackets we may still not be able to survive in the
freezing water engulfing us. In addition, our funded pension schemes
are suffering due to the fall in value of equities over the past 3
years, many defined salary schemes are closing to new members, if not
completely ,and contributions to defined contribution schemes are
currently not at levels to provide employees the same level of benefits
as they would have got under the final salary scheme.

Willetts states that “the best way of ensuring that pensioners have a
decent income in the future is to have a strong and growing economy
with lots of workers producing the output on which pensioners can
draw”. He points out that the important variable is the size of the
work force which can be increased through making the existing
population work more, bringing in more migrant labour or increasing the
fertility rate. However, all three are faced with significant social,
cultural and ethical difficulties and only the latter is likely to
provide a long term solution.

What about the workers?

Getting more work out of the current population would help to produce
more and keep salaries down. However, even if we all work until our
dying day — as many people already do through their provision of
informal care to relatives and friends — the working population is
projected to decline. We will need to keep more people in work for
longer simply to keep the wheels of the economy moving. But older hands
cannot push as hard as younger ones. Reducing unemployment would have a
double effect as it will release more workers into the economy and
reduce the economic drag of benefit payments.

There is also more scope
to get more women into the workforce. However, this is not without its
risks. A huge social experiment is currently underway to see what the
effects on the coming generations will be where large numbers of them
have been brought up by two working parents. It is far from clear that
this is going to be a success. If it is to work there will need to be
greater flexibility in working hours, childcare arrangements and even
in schooling arrangements. The current drive to get more young people
in to university would be in contradiction to trying to get more people
working. This simply delays when many young people start doing the job
they probably would have got anyway without a degree. There are only so
many jobs that really need degree level education around and just
because more people go to university does not increase the number of
jobs that really require three or four years of further education.

Come on in, migrant workers

What about bringing in more migrant workers? At best this would be a
temporary solution as fertility rates among migrants tend to fall to
the same sort of levels as the indigenous population relatively
quickly. Also, there could be serious social problems in both the host
and the home country. The home country could find itself stripped of
its brightest and best, not dissimilar to the brain drain experienced
in the UK in the last few decades where many of the best academics left
for better salaries in the USA. In the host country the sheer number of
immigrants could be too large to absorb without serious cultural

The UN (United Nations Population Division 2004) has projected what
levels of migration would be required under certain future scenarios.
Without any immigration the population of the UK would fall from 59
million in 2000 to 56 million by 2050. In order to maintain the same
Support Ratio (the ratio of those aged 15 – 64 to those aged 65 and
over) the UK would need a total immigration of 60million between 2000
and 2050. The EU as a whole would need 700 million immigrants. Hardly a
practical solution! The trend to outsourcing would reduce the need to
bring workers in but one cannot outsource everything and in particular
one could not outsource the provision of care needed by elderly people.

Given the demographic dynamics it would not be too far fetched to
imagine a team such as Manchester United being made up of mainly

African and Asian players being watched in those countries by millions
of locals and the stands half full of geriatrics giving a whole new
meaning to the anthem “You’ll never walk alone”!

Grow your own

This just leaves the more babies option. In Willetts’ words, “Feminism
is the new natalism”. Whatever that means! Women are having, on
average, fewer and fewer babies.

The following table shows the recent falls in total fertility rates (TFR) in 4 EU countries (Willetts 2003):

1995-2000  2000-2005
 France  2.9 1.76  1.85 
 Germany  2.5 1.34  1.35 
 Italy  2.5 1.21  1.23 
 UK  2.8 1.70 1.60 

Many reasons have been put forward for the decline in fertility from
the biological (lower sperm count) to the economic (greater job
insecurity, reduced availably of council housing, greater participation
of women in the labour force) to cultural (growing secularisation and
individualism, changing attitudes to marriage, co-habitation and
marriage breakdown). That’s quite a list to deal with if one wishes to
reverse the trends.

If Governments were to attempt to do something they could try and
positively encourage more births by social and fiscal measures.
Unfortunately such measures tend only to have a temporary effect. Even
Sweden’s increased fertility rates of the 1980s as a result of an
expanded family policy have fallen. Its TFR was 1.54 in 2000, down from
2.13 in 1990. Also the idea of encouraging people to have more children
simply to fuel the economy of the future has more than a touch of ‘The
Matrix’ about it. Children need to be desired for their own sake.

George Kerevan writing in The Scotsman on 2 August 2003 hit, I
think, the nail on the head when he wrote that “If bribing people to
change their lifestyle does not work – it rarely does as most of us
resist being told how to live by pompous, hypocritical career
politicians – what will raise the birth rate? The answer is all to do
with optimism.”

This is also the explanation provided by the French for
their relatively high TFR. Pope John Paul II (John Paul II 2003) in a
recent document analysing the cultural and religious situation in
Europe stated that “This loss of Christian memory [in Europe] is
accompanied by a kind of fear of the future. Tomorrow is often
presented as something bleak and uncertain. The future is viewed more
with dread than with desire. Among the troubling indications of this
are the inner emptiness that grips many people and the loss of meaning
in life. The signs and fruits of this existential anguish include, in
particular, the diminishing number of births…”

The big question is then: How are we to escape this existential anguish
and give the West — and the rest of the world — the future they

Print references
Clark, Colin. 1967. Population Growth and Land Use. New York. St Martin’s Press.
Ehrlich, Paul. 1968. The Population Bomb.  New York. Ballantine.
Lomborg, Bjorn. 2001. The Skeptical Environmentalist. Cambridge. Cambridge University Press
Malthus, Thomas. 1803. An Essay on the Principle of Population. London.
Mitchell, Donald, O. and Ingco, Merlinda, D. 1993. “The World Food
Outlook” International Economics Department. The World Bank. Washington
Pope John Paul II. 2003. Ecclesia in Europa.
Simon, Julian L. 1996. The Ultimate Resource 2. New Jersey. Princeton University Press.
United Nations Population Division 2000. “Replacement Migration”
United Nations Population Division 2004, World Population Prospects: The 2004 Revision.
Willetts, David. 2003. “Old Europe? Demographic change and pension reform”. Centre for Economic Reform


  • Paul Ehrlich, The Population Bomb (1968): "The battle to feed
    humanity is over. In the 1970s, the world will undergo famines.
    Hundreds of millions of people are going to starve to death in spite of
    any crash programs embarked upon now. Population control is the only
  • “Based on first-hand evidence of your own senses – the improved
    health and later ages at which acquaintances die nowadays as compared
    with the past; the material goods that we now possess; the speed at
    which information, entertainment, and we ourselves move freely
    throughout the world – it seems to me that a person must be literally
    deaf and blind not to perceive that humanity is in a much better state
    than ever before.” — Julian Simon
  • “Greater consumption due to increase in population and growth of
    income heightens scarcity and induces price run-ups. A higher price
    represents an opportunity that leads inventors and businesspeople to
    seek new ways to satisfy the shortages. Some fail, at cost to
    themselves. A few succeed, and the final result is that we end up
    better off than if the original shortage problems had never arisen.
    That is, we need our problems, though this does not imply that we
    should purposely create additional problems for ourselves.” — Julian
  • “To replace the litany with facts is crucial if people want to
    make the best possible decisions for the future. Of course, rational
    environmental management and environmental investment are good
    ideas—but the costs and benefits of such investments should be compared
    to those of similar investments in all the other important areas of
    human endeavour. It may be costly to be overly optimistic—but more
    costly still to be too pessimistic.” — Bjorn Lomborg, “The Truth About
    the Environment”. The Economist, 2 Aug 2001
  •  "So where will the children of the future come from? Increasingly they will come from people who are at odds with the modern world. Such a trend, if sustained, could drive human culture off its current market-driven, individualistic, modernist course, gradually creating an anti-market culture dominated by fundamentalism–a new Dark Ages." ~ Phillip Longman, The Empty Cradle (2004).
  • “ Much of what we loosely call the Western world will not survive this century, and much of it will effectively disappear within our lifetimes, including many if not most Western European countries. There’ll probably still be a geographical area on the map marked as Italy or the Netherlands–probably–just as in Istanbul there’s still a building called St. Sophia’s Cathedral. But it’s not a cathedral; it’s merely a designation for a piece of real estate. Likewise, Italy and the Netherlands will merely be designations for real estate. The challenge for those who reckon Western civilization is on balance better than the alternatives is to figure out a way to save at least some parts of the West… The design flaw of the secular social-democratic state is that it requires a religious-society birthrate to sustain it. Post-Christian hyperrationalism is, in the objective sense, a lot less rational than Catholicism or Mormonism. Indeed, in its reliance on immigration to ensure its future, the European Union has adopted a 21st-century variation on the strategy of the Shakers, who were forbidden from reproducing and thus could increase their numbers only by conversion.” ~ Mark Steyn. “It’s the demography, stupid.” WSJ.com. Jan 6, 2006.

Internet resources

Gary Becker. "Missing Children. Without mass immigration, low birthrates doom society." Wall Street Journal. Sept 1, 2006.
Nicholas Eberstadt. "Doom and demography". Wilson Quarterly. Winter 2006
Nicholas Eberstadt. "Growing Old the Hard Way: China, Russia, India". Policy Review. April/May 2006.
Phillip Longman. "The Return of Patriarchy". Foreign Policy. March/April 2006.
Mark Steyn. “It’s the Demography, Stupid: The real reason the West is in danger of extinction”. WSJ.com. Jan 4, 2006.
Sergei Kapitsa. "Russia’s Population Implosion". Project Syndicate. June 2005.
Phillip Longman. “Missing Children: Can America duck the worldwide baby bust?” Washington Monthly. Dec 20, 2004.
Nicholas Eberstadt. "Old Age Tsunami". WSJ.com. 15 Nov. 2005.

Nicholas Eberstadt. “Russia, The Sick Man of Europe”. Public Interest, Winter 2005.

Stanley Kurtz. “Demographics and the Culture War”. Policy Review, Feb 2005.
Bjorn Lomborg. “The truth about the environment”. Economist. 2 Aug 2001

Julian Simon’s Bet With Paul Ehrlich

Dermot Grenham is chief actuary for the social security, demography and overseas pensions team of the Government’s Actuary Department in the UK. He has held various financial reporting...