The first fifty years of the next millennium will be critical for the world's population. By 2050 population growth should have leveled off, but by then we'll have 10 billion people--two-thirds as many again as we have today.The rate of population growth is something we can choose right now, though: it's not something that just happens, but a matter of human choice. The choice is a complicated one,with many variables, but it remains a choice.
If we want to prevent a population explosion, we should take action now -or assist the poorer countries to do so. They need better government, better institutions, better labor and capital markets, better schools.
Anything that increases the value of women's time and adds to the cost of caring for a child makes a woman less likely to have that child. Since big families are often seen as safety nets for illness and old age, improving poor people's access to insurance, pensions and welfare institutions also has a major impact. This can be as simple as rural credit, providing a means of saving. Finally, there is education--both for women and, perhaps even more important, for the next generation of children.
These steps are there to be taken, but there appear to be some countries that are not seriously trying at the moment. If we cannot achieve that we will certainly not control population.
That said, I don't feel pessimistic that we are going to run out of resources: we are becoming more efficient at producing food faster than the rate at which population is increasing. There is, however, a risk that we will wreck the environment so effectively that the world will no longer be an attractive place to live. That really would be a dismal outcome, to reach world population equilibrium only to find we'd destroyed the natural environment in the process.
世界人口
新千年的前50年对世界人口来说是至关重要的，到2050年，世界人口将趋于平稳，但到那时，世界人口将达到100亿，比现在多2／3。但人D增长率是我们现在能选择的事：它不是顺应天意而产生的，而是人类的选择。这一选择相当复杂，有许多因素，但它依然是一种选择。
要想避免人口爆炸，我们现在就应采取行动——或者说应帮助比较穷的国家来控制人口，因为他们需要更好的政府、机构、劳动力及资本市场和学校。任何使一个妇女增加抚养孩子的时间或抚养孩子费用的事都使得那个妇女不太想要这个孩子。由于大家庭经常被认为是年老生病时的安全网，让穷人进一步获得保险、退休金和福利机构的帮助也会在控制人口生育上起重大作用。这可以像农村信用制度那样简单，为人们提供一种储蓄的手段。最后还有教育问题——既有对妇女的教育，也有更重要的对下一代的教育。
以上这些都是应采取的措施，但看来有些国家目前并没有认真去做，如果我们不能做到这一点，我们就不能控制人口。
及此，我对我们资源殆尽并不悲观：我们生产粮食的速度超过了人口增长的速度。然而，我们也存在这样的危险：我们会彻底毁坏环境，以致于地球将不再是一个吸引人居住的地方。那确实是一个可悲的结果：实现了人口的平衡却换来了自然环境的破坏。
