The probability of our leaving our planet for any other inhabitable one is very low. Therefore we must preserve the one we have in a condition suitable for human life and its continuation. So far, so obvious.
The oil and coal we now use so prolifically was, I understand, laid down some 150 million years ago, when the climate was warm and humid and the major living forms were gigantic tree ferns growing in vast swaps.
We were, at that time, simply a small twinkle is the eye of creation. Now, as we release the energy laid down in that distant past, we risk a return to something like that distant climate, quite unsuitable for mammalian life.
This is, I think, what we mean by global warming, when the vast sub-continents of ice melt, and the expansion of the water in our seas and oceans raises the level of the oceans until much of our coastal land is drowned. (Shetland is likely to become a scattering of uninhabitable islands as the lower land is inundated.)
We call this global warming, and it is what we face unless we reduce our use of fossil fuels, in our use of transport, the heating of our homes for example, or, to retain our standard of living we replace the use of fossil fuels with renewable energy offered by the wind, the tide, the waves, the sun, perhaps others.
That great thinker, Stephen Hawking, suggests nuclear fusion as our future source of energy and, of course, we have very successful plants across the world today using nuclear fusion.
More realistically, we have wind, lots of wind, ready to feed its momentum into our windmills, clean, renewable, a huge contribution to preserving our planet for our children, our grandchildren, and their children down the line. Not to think of them seems to me unutterably selfish.
Many other places have had the foresight to regard windmills as graceful contributors to their energy supplies. (We have seen them in California, in Scandinavia, in Austria, in Scotland, and one beauty overlooking Wellington in New Zealand.) There must be many more.
They love them. So should we.