2.1 Surely it is not population numbers that are a problem, but development, consumption and energy use?

This would be true if populations were much smaller and growing slowly. For example, the population of all Europe west of Russia was about 40 million in the year 1000, and took 200 years to grow to 60 million - about as many people as live in the UK today. These earlier levels of population, even had they been living at 21st century standards, would clearly have caused less impact on the environment than today's European (EU) population alone. Put another way, if we in the UK reduce our carbon emissions by 10 per cent, but the 'emitting' population grows by an equivalent percentage, nothing has been achieved. Of course the nature of development consumption and energy use is important - breakthroughs in carbon-free energy technology or the discovery of non-fossil fuel energy sources would make a very important difference. But in their absence, and with nearly 80 million people being added to the planet each year, population growth is seriously undermining progress on other fronts.

2.2 Global trade allows overpopulated countries to import what they need from other countries. What's wrong with that?

Nothing, up to a point - the point at which resources begin to dry up. In the case of agriculture, rising global temperatures, falling water tables and soil erosion are already causing resources literally to dry up, and efforts to reduce the number of undernourished people in the world (estimated by the WHO at about 840 million) are having little success. Improved technology (for example, GM food) does not always offer a solution. In the case of non-renewable resources, and the point at which imports deprive the exporting community of essentials for themselves, in the case of renewable resources. Globalisation may hasten economic growth, but it masks underlying long-term resource problems by intensifying international competitive price pressures, which in turn increase supply and hasten exploitation and consumption of non-renewable resources. Live now, pay later. Oil is an example. New supplies from Russian fields have been providing competition with OPEC oil producers, causing downward pressure on prices, which, in the absence of war, lead to more rapid consumption of finite oil reserves.

OPT's sustainable population (maximum carrying capacity) estimates are calculated on the basis of a need to live off renewable biological resources - in economic terms, to live off the interest on biological capital rather than to deplete biological capital. OPT is aware that the simplest way to reduce the size of an industrial country's ecological footprint is to reduce its imports of natural resources until they match its exports of natural resources. On the other hand, we realise that it will be difficult for developing countries to prosper unless they have a fair market abroad for their processed goods. We recognise too that apparent concern about the environment can be protectionism in disguise. In any case, it would help to clarify the issues if environmental costs were gradually 'internalised' - i.e. incorporated into the price of products. If all countries were to achieve low sustainable population targets, there would be more room for international trade without resource depletion.

2.3 Is OPT a development organisation or an environmental organisation?

That is a question to which we cannot give a simple answer. As our main objective is to help bring about a situation where the option of a good quality of life is available worldwide, we are clearly in favour of 'development'. However, we are very much aware of ecological limits. Until a balance is achieved between human numbers and natural resources, we do not believe that the major human - and environmental - problems can be solved. Millions of people will continue to starve and/or live in squalor and/or die in resource wars and/or die from preventable illness and/or suffer from appalling poverty and/or suffer from abuse of human rights. More than 70 million people already die of starvation each year, and 42 million are suffering from AIDs. More people will die. More species will be lost. More carbon will build up in the atmosphere. More rainforests will be destroyed. More air, water and land will be polluted.

2.4 Does population growth increase poverty? Or is development the best contraceptive?

Population growth maintains poverty in many parts of the world. It is difficult for a resource-poor country with rapid population growth to increase its economic 'cake', even if that cake is increasing, because each slice is rapidly having to be divided between ever more individuals. An increase in population (still doubling in less than 30 years in several countries) will wipe out gains faster than they can be made, whether in agriculture, education, literacy or healthcare. (For example, a recent Minister of Health in Morocco maintained that every year his country needed to build nine hospitals, 8,500 classrooms and 150,000 houses - and create 280,000 jobs - just to keep up with population growth.)

Poverty, if maintained, increases population in many parts of the world. In rural poverty, reduction of family size appears disadvantageous - every mouth has two hands for work. The labour of each new child in the family is welcomed, as a form of social security for sickness and old age. High child mortality also tends, unsurprisingly, to reduce interest in birth planning until a relatively high average family size is achieved. This tends to be emphasised by development agencies who ignore the fact that population increase maintains poverty (as above). Often these NGOs, consider increasing numbers passively, as a demographic fact that has to be coped with, by development. OPT believes that any plan for sustainable development needs to include a plan for widespread access to voluntary birth planning. The evidence is that if birth planning services are supplied, they are taken up - for example in Thailand and Costa Rica, and in the State of Kerala in India. So development is not a contraceptive on its own - contraceptives are the best contraceptive. Whether overpopulation causes poverty or poverty causes overpopulation is a chicken-and-egg argument: development and contraception are joint solutions. By offering contraception, the vicious circle of population growth and poverty can be broken, without coercion. International aid, therefore, needs to be combined with comprehensive, affordable and holistic birth planning services, so that no woman (or man) who wishes to control her (or his) fertility is denied the means to do so.

2.5 The dictionary definition of development is 'realisation of fuller and greater potential'. This implies qualitative change, not quantitative change. So why should development require economic growth?

We accept that a good case has been made for believing that, in industrial countries at least, there can be an improvement in quality of life without a corresponding improvement in material standard of living. For example, growth in environmentally destructive sectors of the economy, such as air transport, could be replaced by growth in the renewable energy sector of the economy. One way of highlighting this is the use of alternative economic indicators such as the Index of Sustainable Economic Welfare, which we welcome. In poor countries, however, we are convinced that economic growth is an essential element in development - i.e. improvement in quality of life, although greater efficiency will help. The various reports of the UN Human Development programme all stress this.

2.6 How can low-population countries survive in a global economy dominated by high-population countries like the USA?

By specialisation in some industries and areas of activity, and by collaboration in others. (As well as by better productivity and innovation.) The UK, as one of 15 members of the European Union, shares its collective power in agreed areas.

2.7 Why is a growing population always thought to be necessary for a growing economy?

We don't know, but it isn't, except on the simplistic assumption that 100 million people can produce more than 50 million. What matters is per capita economic growth (a higher standard of living for a population of 50 million, not a lower standard of living for a population unnecessarily increased to 100 million). A growing population is also cited as one that has a growing workforce to support increasing older people. Unfortunately the extra people coming into the workforce (unless they are strictly temporary guest workers) will grow old too, and to keep such a 'pyramid scheme' going, perpetual population growth is necessary. Russia's population has been declining since the end of Communism, but in 2002 its GDP growth rate, at about 4.4%, was one of the highest in the world. China, whose population is growing only slowly due to a one-child population policy, achieved an near-10% growth in GDP in 2003. Would China be consuming more of the world's resources faster if its population were growing at higher speed? (One demographic estimate is that without its one-child population policy, China would now have an extra 300 million consumers - the equivalent of more than three countries the size of Germany.) Countries with rapidly growing populations are among the poorest economies in the world. What matters most of all is not simple per capita economic growth, but an improvement in the quality of life.

2.8 What is your attitude to international trade?

Equivocal - a difficult issue. On one hand OPT is aware that the simplest way to reduce the size of an industrial country's ecological footprint is to reduce its imports of natural resources until they match its exports of natural resources. On the other hand, developing countries cannot prosper unless they have a fairer market abroad for their goods. We realise too that apparent concern about the environment can be protectionism in disguise. In any case, we believe it would help to clarify the issues if environmental costs were gradually 'internalised' - i.e. incorporated into the price of products. If all countries were to achieve low sustainable population targets, there would still be room for international trade.

2.9 What is your attitude to technology?

According to the formula I= PAT, environmental Impact is the product of Population, Affluence (consumption) per person and Technology. The challenge is to reduce A. Some people have greater faith than we do in the potential of improved T to achieve this. Not surprisingly, we think P is the key factor. Nevertheless, we do believe technology has a very major role to play. For example, it will not be easy to reduce P without improvements in contraceptive technology. And much will depend on the development of efficient biomass, solar, wave, wind, and other forms of renewable energy technology. You could say that as technology was largely responsible for getting us into the present mess, it had better help to get us out of it... reversing the damage will need a great deal of ecologically sound technological innovation.

2.10 What is your attitude towards enforced sterilisation?

We are totally against any such action or policy.

2.11 Do your ideas or recommended policies have anything to do with eugenics or 'designer babies'?

No.

2.12 Why not just allow AIDS to reduce world population?

It's unthinkable. Because a population policy should aim to save lives. Increasing death rates, whether by famine, disease or climate change, is Nature's way of reducing population, and is not a humane population policy.

2.13 You emphasise the need for an improvement in the quality of human life but have little to say about animal welfare. Why is this?

Humans are mammals and therefore part of animal life. The quality of human life is also intimately connected with the well-being of other animals: according the United National Global Environment Report of May 2002, about a quarter of the world's species of mammals are threatened with extinction within 30 years - as a result of human activities. While the disappearance of a few species may not make much difference (setting aside the moral case for sustaining other species), the elimination certain species can disrupt important ecological processes and a mass extinction of animal and plant species would destroy human life. All animal and plant life form part of the complex ecological life-support system that sustains humans.

2.14 In your list of aspects of life that would improve as a result of population reduction you mention 'greater national security'? Can you explain?

Look at current events in the Middle East, in which territorial claims and the 'need' for oil, or oil revenues, play a part. Allowing a country's population to decline reduces both its need for extra land and its dependency on imports of raw materials (excluding the extra demand caused by higher per capita material consumption). If the population of the USA had stabilised in 1945 at a total of 135 million, it would not now be dependent on imported oil. If Iraq's population had not expanded so rapidly, it might have been able to benefit more from oil revenues. The Israel/Palestine conflict involves fighting over scarce disputed territory and migrating, settling populations. Population growth multiplies existing pressures. Beyond a certain point, population increase makes a country weaker, not stronger, and increases the chance of warfare. Looked at from the other side of the coin, the nature of warfare has also changed. Large populations can be threatened by small, highly motivated groups with access to nuclear or biological weapons. The most destructive enemy of the USA in 2001 was the Al-Qaeda terrorist group, not the former USSR. In 2003, the USA (in population terms a quarter the size of China) showed itself to be the world's military superpower.

2.15 When I try to discuss population, I am accused of 'playing a numbers game'. What does this mean?

Nothing useful. Population cannot be discussed without mentioning numbers - and demographics is about numbers. Daily life cannot be carried out without using numbers. If you phone a restaurant and you ask to book a table, is the response 'Don't play the numbers game with me'? No. If you ask 'Is red wine good for me?' the answer cannot be a simple 'yes' or 'no'. One or two glasses a day might be good for you, but three glasses will probably be less so, and one or two bottles a day will do you harm. Individuals, businesses, governments, nations and international communities cannot plan without knowing the numbers of people those plans have to be made for, and whether those numbers can be provided for. Political issues can be discussed without mentioning numbers, for example, from a sociological point of view, and that discussion can be helpful. But without referring to number or quantity - essential to science, economics and daily life - the conclusions of any such debate would be simply part of a greater whole. Numbers are as essential as words. Without using them the human race cannot function.

2.16 Doesn't a nation need a large population to succeed in international sport?

Senegal's football team beat France in the 2002 World Cup. Greece and Portugal were the finalists in the Euro 2004 football contest - not England, France, Germany or Italy.

2.17 Would you describe yourselves as optimists or pessimists?

Both: we are realists. Pessimism: we accept that getting human society on to a sustainable path is going to be a painful process. (For example, achieving population stabilisation and reduction involves a transitional stage where a population ages.) But the longer action is delayed, the more difficult it will be. On the other hand, we believe it is still possible, and we are making our small contribution to helping to achieve this. OPTimism: we believe the best in human nature - that individuals want to do the best for their fellow humans, for future generations and for Earth. If population policies can be introduced in time and worldwide, a great deal of human suffering will be avoided.

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