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.

The density of human population combined with the development of powerful and largely unconstrained technology has given us the problems of the anthropocene and the serious possibility of self-caused extinction.

Obama's clean power plan, methane regulations, and increased fuel economy standards are about as good as our political system can do at this point in our history. Let's embrace these things, make them work, and push for more, rather than denouncing them because they're 9th best (which they are).

I begin with human psychology and then see what we can say about ethics.

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.

We can use economic instruments to help realize our goals but economics does not tell us what our goals should be.

We live on a restless planet in a violent universe.