Brady: It's almost impossible for me to imagine a situation that is useful. I think this is purely an intellectual exercise, which might be part of the reason why the fighting over it is just so enormous. And without a doubt, thereis a huge amount of uncertainty about the origin of many diseases. But even if that's wrong, even if it didn't come from domesticated animals, nobody disagrees that. You still can't have plagues if you don't have a big enough population. So it doesn't even matter if that part of the book is wrong. An, i just love the idea of someone just losing it at their computer screen.