The potential for alternative energy sources, mainly solar and wind power, to completely replace coal and gas for utility generation globally is, I think, certain. The question is only whether it takes 30 years or 70 years.

Market timing, by the way, is a tag some buy-and-hold investors use to put down anything that involves using your brain. These are the same people who like to watch the locomotive coming and get run down in the name of discipline.

Think how weird profit margins are: We've got high unemployment and financial crises - and world record profit margins. People think the American market is very cheap. We don't. The market quite incorrectly gives full credit to today's earnings.

At least us old men remember what a real bear market is like, and the young men haven't got a clue.

You don't get rewarded for taking risk; you get rewarded for buying cheap assets. And if the assets you bought got pushed up in price simply because they were risky, then you are not going to be rewarded for taking a risk; you are going to be punished for it.

The language "it's too late" is very unsuitable for most environmental issues. It's too late for the dodo and for people who've starved to death already, but it's not too late to prevent an even bigger crisis. The sooner we act on the environment, the better.

I like to be right. I try not to miss the big ideas, forget the little ones, and try to get them right. End of job description.