I think Americans are always going to care more about Americans than about Mexicans.

When people want to inspire you to turn against some group of people, they'll often use empathy. When Obama wanted to bomb Syria, he drew our attention to the victims of chemical warfare. And in both of the Iraq wars, politicians said, "Look at the horrific things that are happening." I'm not a pacifist. I think the suffering of innocent people can be a catalyst for moral action. But empathy puts too much weight on the scale in favor of war. Empathy can really lead to violence.

I have huge admiration for people who think like the effective altruist, who try to rationally think about how they can change the world for the better, and who try not to be swayed by irrational considerations, such as skin color or whether or not someone lives in the same neighborhood.

My younger son told me nobody uses email anymore. I'm this old fogie with my email. I don't know what I'm supposed to communicate with now - SnapChat?

We don't just respond to things as we see them, or feel them, or hear them. Rather, our response is conditioned on our beliefs, about what they really are, what they came from, what they're made of, what their hidden nature is.

I have two teenage sons, and they're both surviving, thriving, and having a great time, and they're always on social media.

It's hard to pull apart empathy from compassion. What is really clear is that we innately care for other people at least to some extent.