Many people theorize poverty, but so many elements of poverty, individually, for most people who theorize about poverty would be really difficult to even comprehend the individual things. Just take homelessness. If you are homeless, what does it mean not to have a post box where people can contact you; what does it mean not knowing where you're going to sleep at the end of the day; what does it mean not having a place where you can store what little you might possess. So dealing with homelessness in itself is a huge thing for most people who are commentators [on] or benefactors to poverty.

Currently, we allow our political and business leaders to get away with murder. Now is the time to change that. We need direct liability for those who are destroying our future and this planet. We need fast, profound and systemic change. History only moves forward when courageous people get up and act. That's why I support this citizens' initiative to recognise ecocide as the crime it is.

This week we saw progressive business and faith leaders making strong commitments that are moving ahead of what world leaders promised today. The leaders of major economies must be bolder than they were today in providing a vision for 100% renewable energy for all.

You know how they say, 'What happens in Vegas, stays in Vegas?' What happens in the Arctic doesn't stay in the Arctic.

My final advice for young people is to not wait for leadership from adult politicians. Step forward today, because our current leaders are denying the dire reality we are facing. Leadership can come form anywhere.

I think even though he [Nelson Mandela] was feted and praised as he was, he always was at pains to say, I'm a human being.

Sandy was a climate change warning. Obama must now take the stage and fulfil the promise of hope the world needs.