The real requirement, if we are to avoid runaway global warming, is probably 80% by 2030, and almost no burning whatever of fossil fuels (coal, gas and oil) by 2050.

War is part of our history, but it is not in at all the same sense part of our prehistory. It is one of the innovations that occurred between nine and eleven thousand years ago when the first civilized societies were coming into being. What has been invented can be changed war is not in our genes.

As the most religious country of the 18 surveyed, the U.S. also comes in with the highest rates for teen pregnancy and for gonorrhea and syphilis.

Never did anyone ever stay longer than ten years because the resistance grows fiercer as your presence grows longer [in Afghanistan]. I don't think we are going to be any exception. What made us exempt from history?

While the high-level climate talks pursue their stately progress towards some ill-defined destination, down in the trenches there is an undercurrent of suppressed panic in the conversations. The tipping points seem to be racing towards us a lot faster than people thought.

But we are almost certainly going to miss our [global warming] deadline. We cannot get the 10 lost years back, and by the time a new global agreement to replace the Kyoto accord is negotiated and put into effect, there will probably not be enough time left to stop the warming short of the point where we must not go.

The first and most important impact of climate change on human civilisation will be an acute and permanent crisis of food supply. Eating regularly is a non-negotiable activity and countries that cannot feed their people are unlikely to be reasonable about it.

Fiat justitia, ruat coelum. (Do the right thing even if the heavens fall.) It's not nearly as naïve a maxim as it seems, because in the real world it often turns out that doing what is morally the right thing is also, in practical terms, the right thing to do.