In the paperback's afterword, Victor Stenger addresses criticisms of his New York Times bestselling first edition.

Throughout history, arguments for and against the existence of God have been largely confined to philosophy and theology. In the meantime, science has sat on the sidelines and quietly watched this game of words march up and down the field. Despite the fact that science has revolutionized every aspect of human life and greatly clarified our understanding of the world, somehow the notion has arisen that it has nothing to say about the possibility of a supreme being, which much of humanity worships as the source of all reality.

Physicist Victor J. Stenger contends that, if God exists, some evidence for this existence should be detectable by scientific means, especially considering the central role that God is alleged to play in the operation of the universe and the lives of humans. Treating the traditional God concept, as conventionally presented in the Judeo-Christian and Islamic traditions, like any other scientific hypothesis, Stenger examines all of the claims made for God's existence.

He considers the latest Intelligent Design arguments as evidence of God's influence in biology. He looks at human behavior for evidence of immaterial souls and the possible effects of prayer. He discusses the findings of physics and astronomy in weighing the suggestions that the universe is the work of a creator and that humans are God's special creation.