I find the parallels between how some investors refuse to recognise the trends and our reaction to some of our environmental challenges very powerful. There is an unwillingness to process unpleasant data.

Some societies are also more optimistic than others: the U.S. and Australia are my two picks Tell a European you think there’s a housing bubble and you’ll have a reasonable discussion. Tell an Australian and you’ll have World War III. Been there, done that!

Battering down solar cells on the roofs of Wal-Marts in California. I think that will be some of the highest-return investments that anyone ever makes.

Remember that history always repeats itself. Every great bubble in history has broken. There are no exceptions.

Investment bubbles and high animal spirits do not materialize out of thin air. They need extremely favorable economic fundamentals together with free and easy, cheap credit, and they need it for at least two or three years. Importantly, they also need serial pleasant surprises in such critical variables as global GNP growth.

By background I'm both a Quaker and a Yorkshireman, which I like to call double jeopardy.

We live on a finite planet. We have finite resources, and we're running out of good, arable land.