I think it's very important to invite and encourage people to talk about climate change who have a lay understanding. In general, there is a lot of confusion among climate activists about the role of science, that scientists should be social and political leaders of this movement.

With climate change, of course there are things to grieve. I certainly grieved that the vision that I had for my life, that I would be a clinical psychologist and write books and have a family, that that was not going to happen, because if the world is collapsing around you, it just doesn't seem that appealing anymore.

I argue that I don't think it's a moral position to say that civilization is going to collapse, and that's okay. Because that would cause the deaths of billions of people. It's certainly not something I'm willing to accept.

Psychologically speaking, the rational, healthy response to climate change is to say to oneself, "What can I do about this?" But that question is often answered through individual action.

Social movements throughout history take place in people's minds. If we got 5,000 Americans who were talking about climate change to their neighbors and to their coworkers, and talking about this pledge, that would change the political and social landscape so much more than if 5,000 people got arrested for protesting a pipeline.

I think 99% of climate scientists would agree that we need to reduce emissions as quickly as possible, and then begin removing greenhouse gasses and carbon from the air. And if we don't do that we are looking at some range of catastrophe.

By looking the other way on climate change we facilitate a collective denial, and we do it for each other.