MADAM - It will probably surprise Nick James to know that I agree with quite a lot in his letter.

The growth of economies in a finite world is in the end impossible.

As someone said, if anyone thinks you can have infinite growth in a finite environment, he is either an idiot or an economist. However, much of the world lives in poverty, which is a state of the world that no one wishes to see (I believe the number of people in absolute poverty is over a billion) and their economy at least must be allowed to grow, for humanity’s sake.

To support the present population at the level that it is at the present we need about one and a half Earths.

We are living on our capital, and nature cannot replace renewable resources as fast as we are using them.

Overshoot Day, the day in each year when a year’s supply of resources is used up, occurs earlier each year, and was on August 20 in 2013.

In order to reach an equitable state, therefore, we will have to reduce per capita consumption.

However, if the whole world consumed at the average rate of the present developed world, we would want not one and a half Earths, but three and a half.

We would have to reduce per capita consumption to one over three and a half, or two sevenths, of the present.

Now, consider the distress produced by the austerity measures introduced by the present government.

These cuts are nothing like the 5/7 cuts that would be required.

Nick, could you stand a reduction of that order?

None of us, however much we tried, could do that.

We would have to cut not only our personal expenditure, but a similar proportion of consumption carried out by others on our behalf.

Imagine a 5/7 cut in education, hospitals, roads, security, food supply, water, sewage, waste disposal, etc.

I doubt if even the very greenest of Greens would welcome that, but how would you persuade the rest of the population to agree to it?

Only the most oppressive of governments would attempt it.

And supposing we did succeed in that reduction over a given period, what if the world’s population had increased by a corresponding amount in the same period: we would be not one whit further forward.

Population advocates have always known that the reduction of consumption is necessary because they, more than most, recognise that the world is finite.

According to the United Nations, over 40 per cent of all pregnancies are unintentional, and this number, by coincidence, is almost the same as that by which human numbers are increasing.

Over 200 million women have no access to a modern method of contraception (UN).

A result of this is that there are 42 million abortions, of which 20 million are unsafe (WHO).

Annually, 200,000 women die as the result of pregnancies they did not want. All that is lacking is political will.

There are well-established ways of reducing fertility, entirely non-coercive, and several countries have applied these with dramatic results.

Roger Plenty

Stroud