One person looks around and sees a universe created by a god who watches over its long unfurling, marking the fall of sparrows and listening to the prayers of his finest creation. Another person believes that life, in all its baroque complexity, is a chemical aberration that will briefly decorate the surface of a ball of rock spinning somewhere among a billion galaxies. And the two of them could talk for hours and find no great difference between one another, for neither set of beliefs make us kinder or wiser.