Science fiction, to me, has not only things that wouldn't happen, but other planets.

Religions in general have to rediscover their roots. In Hinduism and the Koran, animals are described as equals. If you walk into a cathedral and look at the decorations of early Christianity, there are vines, animals, creatures and birds thriving all over the stonework.

Eating is our earliest metaphor, preceding our consciousness of gender difference, race, nationality, and language. We eat before we talk.

It was exciting to work with director Jennifer Baichwal, who made Manufactured Landscapes and others, on the film of Payback: Debt and the Shadow Side of Wealth. It's called, simply, PAYBACK. Jennifer didn't want to do a transliteration of the book, a kind of illustrated version, but to go into the core of the book: owing and being owed, paying and paying back, on all sorts of levels. So she found real-life, visceral stories that embodied the themes of the book.

Why is it we want so badly to memorialize ourselves? Even while we're still alive. We wish to assert our existence, like dogs peeing on fire hydrants. We put on display our framed photographs, our parchment diplomas, our silver-plated cups; we monogram our linen, we carve our names on trees, we scrawl them on washroom walls. It's all the same impulse. What do we hope from it? Applause, envy, respect? Or simply attention, of any kind we can get? At the very least we want a witness. We can't stand the idea of our own voices falling silent finally, like a radio running down.

I grew up in the golden age of Flash Gordon and sci-fi.

I particularly like Twitter, because it's short and can be very funny and informative. It's a little bit like having your own radio program.