"Humanity is at a tipping point. We stand at a crossroads of accelerating change unlike anything ever seen in the history of life. It feels as if the future could tip either way, between utopia and apocalypse.   The risks we face are daunting. But beneath the rampant pessimism for our future is evidence that humanity can not only survive the coming centuries but thrive deep into the future. No one knows what comes next."    THE HUMAN FUTURE: A Case for Optimism