One of the world's most beloved and bestselling writers takes his ultimate journey - into the most intriguing and intractable questions that science seeks to answer. In A Walk in the Woods, Bill Bryson trekked the Appalachian Trail - well, most of it. In In A Sunburned Country, he confronted some of the most lethal wildlife Australia has to offer. Now, in his biggest book, he confronts his greatest challenge: to understand - and, if possible, answer - the oldest, biggest questions we have pos