In a televised debate about religion and science held at La Ciudad de las Ideas, the international conference of ideas in Puebla, Mexico, in November 2010, the prominent British evolutionary biologist and atheist Richard Dawkins took a novel tack: he argued that our understanding of physics is the new major source of proof that any assumption of a “creator” is unnecessary. By then, Dawkins had been using biology and evolution to argue against the existence of God for many years. I was there on the stage with Dawkins in Mexico, and the experience led me to the thesis of this book: that science has not provided any proof that the existence of a divine creator of some kind must necessarily be false. And in the chapters that follow I will show that we have by no means reached the point at which people can claim, in the name of science, that God does not exist.