For two decades I have queried the meaning of the word sustainable. The concept emerged in the 1972 Stockholm Conference on the Human Environment. The notion became associated with climate change and the creation of IPCC in 1988. And at the 1992 Rio Earth Summit sustainable became a watchword associated with development and led to the notion of Consensus applied to Science. David Henderson says 'sustainable' has been endorsed by governments as a whole but the sense in which it appears in research and policy documents is generally not clear.

In both public and private investment, good projects are hard to find. Investments should be subject to economic Darwinism which weeds out the inefficient. And times change, so that once efficient entities like Marks and Spenser or General Motors pass their sell-by date.

At a recent Cambridge Seminar on the inefficiency of technological lock-in [TLI] my confusion was dispelled. One example of TLI is owning a nearly new machine when a better one becomes available. Repeated questions revealed that in many UK and EU official documents, 'sustainable' means reducing carbon emissions! Imagine the cost of applying this constraint on all economic activity?

Suppose we are barking up the wrong tree? Review of current science [Fred Singer] says

The added forcing from increased solar radiation reaching the earth's surface has contributed nearly 10 times as much energy as greenhouse changes! When compared to the overall greenhouse forcing since pre-industrial times, it's four times larger. If increases in solar radiation reaching the earth's surface in the last 20 years are 10 times greater than that from carbon dioxide, and four times greater than the greenhouse gas changes in the last 150 years, which is more important? Don't forget that it is accepted in climate science that the warming of the early 20th century, about 0.4 degrees C, is due largely to solar changes...So the recent changes in received solar energy should have exerted a tremendous influence on temperature!

Imposing carbon reduction constraints on the world's economic activity is likely to be unfortunate TLI which will cost us all dearly.

Kyoto is unwise in light of current knowledge. Perhaps the celebrated David Bellamy, about to be replaced as president of Plantlife International, and the Royal Society of Wildlife Trusts because he refuses to believe that global warming is man-made, should be reinstated?