The Darwin industry produces biographies regularly, but this one has a rare combination of emotional power and historical authority. Annie's death seems to have reinforced Darwin's doubts about religious consolation. As the author of a theory that relieved God of any responsibility for creating new species, Darwin found it hard to believe that he intervened in human life. And as a grieving parent, he found it impossible to see this death as part of any divine plan. It might have an explanation, even a cause, but no reason. Keynes's Darwin, in other words, is a thinker facing up to the realities of the secular world most of us now live in.