Recent breakthroughs in science show we have just the capacities we need to face our planet's challenges. We're "soft-wired" for cooperation, empathy, fairness, along with a deep need to "make a dent," as social philosopher Erich Fromm put it. My hunch is that one reason depression is a global pandemic is that the dominant mental map denies so many of us expression of these deep needs and capacities.

For me hope isn't wishful thinking or blind faith about the future. It's a stance toward life - one of curiosity and humility.

The good life may mean doing some things that do not feel comfortable. It may mean sitting long hours just with yourself as you begin to listen to your own questions. That was the reality for me when I was 27, and it was really terrifying.

My children threw me a life line: "Return to your roots - food - and rewrite your first book, Diet for a Small Planet." I learned that if I could just show up, in this case, if I could just get myself out of bed, get to the computer in my tiny office at MIT, and start writing, help would start arriving.

How we frame the world - how we talk about it and define it - affects how we see things and how we live.

Because we are living in a culture increasingly dominated by fear where many feel blocked.

I never like to use those terms [like pessimistic].