The recent downgrading of the UK's credit rating brings into sharp focus the dilemma faced by Western economies ("UK's AAA credit rating is downgraded", The Herald, February 23).

They are all without exception pursuing the holy grail of economic growth. Yet common sense tells us the world economy cannot grow exponentially forever. We cannot consume renewable resources faster than they are replenished or they will disappear. We cannot pollute the air and the water faster than the pollutants can be absorbed or we poison ourselves.

We all know this, of course, and the evidence of over-consumption is all around us: deforestation, habitat destruction, over-fishing, species extinction, acidification of the sea, atmospheric pollution, the list is long and getting longer.

We are assured by our leaders that technology will enable sustainable economic growth into the future: wind power, wave power, shale gas and green nuclear power. Yet a moment's thought tells us the latter two will create even more problems of pollution and the former have yet to be proved.

The truth is that even if we could discover some inexhaustible non-polluting energy source the problem would not go away. As WS Jevons demonstrated in 1865, we would simply consume the resources even faster and produce even more waste. Anyway we already have such a source of energy. It's called the Sun.

The term sustainable economic growth is contradictory. The economy is only sustainable in the long term if it does not grow beyond the capacity of the earth to renew what is consumed and absorb the waste created.

What we should be aiming for is sustainable economic activity which produces wealth but does not grow. Such a system can produce prosperity for all over the long term and preserve the planet for future generations.

The world economy has grown almost continuously for the last 200 years and we already consume resources faster than they are renewed. Despite this two-thirds of the world's population have less food, worse water and poorer health care than the average British dog.

If we and our children are to prosper we must learn to consume less and waste less. Striving for economic growth will not achieve that.

Bob Drysdale,

Millfield, Star,

Glenrothes.

When are they going to wake up? The Bank of England is considering lowering interest rates below zero. But the problem is not a supply-side problem. There is nothing wrong with the supply side of the economy that wasn't there before the economy collapsed. The problem is on the demand side.

The economy is moribund because of the lack of demand. The Government's austerity programme, which only affects the lower paid, is the reason why cutting spending does not lead to reduction of debt, as the lower paid are the ones who spend most of their income, so generating demand. Instead we look to foreigners to generate demand by buying our goods. They, however, are doing exactly what we are doing – cutting demand by squeezing spending.

The economy will recover eventually, it always does, but at what cost?

Joe Melone,

85 Drumover Drive,

Glasgow.

The idea being promoted of naming and shaming those who avoid paying tax is absurd ("Naming and shaming of tax avoiders is long overdue", The Herald, February 19).

Tax avoidance (not to be confused with tax evasion) is perfectly legal and every self-respecting accountant has a duty to his clients to ensure they pay the minimum amount of tax possible, within the framework of the law.

Those who should be "in the dock" for tax avoidance, and thoroughly ashamed to be there, are those who failed to close all the known tax loopholes, namely Messrs Brown, Darling, Osborne and their predecessors, all of whom avoided radical tax change and fiddled with tax regulations, allowing perfectly legal tax fiddling to continue unchecked.

Joseph G Miller,

44 Gardeners Street,

Dunfermline.