We need to use economic instruments such as carbon taxes, cap and trade, tax and dividend and whatever else to help incentivize behavior that will move us to a post-carbon, post-animal agriculture world, and make our societies more resilient to the shocks that are already baked into the system. But that doesn't make climate change an "economic issue."

I think when it comes to climate change, the single most important thing in the world is for the United States' Congress to pass an effective bill that will put a price in carbon because if it starts costing something to emit carbon, this will provide an incentive, people do act on the basis to some extent of economic incentives to emit fewer greenhouse gases.

Sometimes I say philosophers should be at the table because they're the only people who know that they're not going to walk away with big money to support their research or to fund their crackpot solutions.

In trying to develop an impartial, expansive ethic we are trying to get ethical systems to do something which they did not evolve in order to do. This doesn't mean that it can't be done or that we shouldn't try to expand the reach of our ethical frameworks, only that there are reasons to be skeptical about its success.

The only way major change in environmental policy is going to happen, the only way, is if there is a very strong, very active popular movement that demands it and such a movement would be unparalleled because it would be a popular movement that says, "Raise our taxes so that we change our behavior."

If you're interested in doing something about climate change as we all should be, all of us who care about future people and creatures that will inhabit this world. Then buying a Prius is a good thing but an even better thing would be to be on the streets demanding urgent action from the United States' Congress.

When it comes to climate change it's all the usual barriers: greed, mendacity, ignorance, short-sightedness and so on, manifest in the extreme power of corporations, the weakness of government, and the indifference of citizens.