The darkest fears of the leading lights and rising stars of science, brought together by the Edge's John Brockman, could keep us all awake at night

WARNING: read the subtitle of this book first. Its editor, cultural impresario John Brockman, may well have you struggling to get your shut-eye as he sets out to keep us on our toes.

The trick this time lies in the tone of a book of answers to questions that Brockman poses annually to science's great and good on his Edge website. It's really not all good news.

In 2007, Edge asked what we were optimistic about. Six years later, the tone sounds like a pessimistic rejoinder: what shouldwe be worried about? But with Brockman it's rarely simple. He invited people to share a scientific worry that might not be on the popular radar, or one they think should drop off the radar. ...

At the end of the exercise, Brockman's crew has left us with a net balance of new fears. But they also introduce us to some big ideas. As psychologist Daniel Goleman puts it: "Effective worrying focuses our attention on a genuine threat and leads to anticipating solutions." Or perhaps biologist Craig Venter is onto something when he writes, hopefully tongue in cheek: "As a scientist, an optimist, an atheist, and an alpha male, I don't worry."