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.

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

We're good at noticing sudden movements of middle size objects in our immediate visual field, but what is out of sight is for us is largely out of mind.

Critics of Consequentialism have often assumed that hedonism (or preference-satisfaction) must be the theory of the good, that the deontic principle must be maximizing, and that the principle should be applied to individual acts. Indeed, this version is often called "classical utilitarianism" and attributed to Bentham and sometimes even to Mill. Rather than a "classical" view it is a recent construction foisted on to the tradition.

Since for me moral demands necessarily flow from human psychology, I don't think we can be obliged to do something that we are not motivated in any way to do. In other words, I'm an "internalist" about morality.

If you have a flat, fixed view of state interest then it is difficult to understand why some states adopt aggressive climate change policies, even when that risks economically disadvantaging them, and other states do not even when it would be in their economic interests to do so.

Philosophers tend to radically underestimate the distance between abstract principles (such as "reduce suffering") and what it might actually mean for people to act on them.