While I think in principle people should not have irrational beliefs, I should say that as a matter of fact, it is people who hold what I regard as completely irrational beliefs who are among the most effective moral actors in the world, in many respects. They're among the worst, but also among the best, even though the moral beliefs are ostensibly the same.

There have been repeated cases when nuclear war came ominously close, often a result of malfunctioning of early-warning systems and other accidents, sometimes [as a result of] highly adventurist acts of political leaders.

After World War II there were many Jews who remained in refugee camps...President Harry F. Truman called for the Harrison Commission to investigate the situation in the camps and it was a pretty gloomy report. There were very few Jews admitted into the United States.

Sea level rise and destruction of water resources as glaciers melt alone may have horrendous human consequences.

Of course all such conclusions about appropriate actions against the rich and powerful are based on a fundamental flaw: This is us, and that is them. This crucial principle, deeply embedded in Western culture, suffices to undermine even the most precise analogy and the most impeccable reasoning.

Anarchism, in my view, is an expression of the idea that the burden of proof is always on those who argue that authority and domination are necessary. They have to demonstrate, with powerful argument, that that conclusion is correct. If they cannot, then the institutions they defend should be considered illegitimate. How one should react to illegitimate authority depends on circumstances and conditions: there are no formulas.

As for geoengineering, there have been serious general critiques that I think cannot be ignored, like Clive Hamilton's, along with many positive assessments. It is not a matter for subjective judgment based on guesswork and intuition. Rather, these are matters that have to be considered seriously, relying on the best scientific understanding available, without abandoning sensible precautionary principles.