I completely accept the science of climate warming, yet I don't always do the right thing by my heirs. Why is that?
The simple answer is, because I'm human. But scientists offer more nuanced insight into why it's hard to be beneficent to people of the future, even our own. The fancy name for this insight is*"intertemporal discounting," which simply means that we humans are selfish and shortsighted when it comes to using finite resources. We prefer to use our resources -- cash, oil, cool days -- for ourselves, now, in the present. And the further off in the future the beneficiaries are, the less likely we are to sacrifice for them. This is because of a failure of imagination: It's supremely difficult to project ourselves into the future, even harder to take the part of another.