Some people regard scientific and religious claims as inherently contradictory because they are unwitting captives to a second type of atheism, which we can call philosophical atheism. This is the dogma that material and natural reality is all that exists. Everything else must be illusory. Biologist Francis Crick admits that his commitment to materialism and his hostility to religion motivated him to enter his field. “I went into science because of these religious reasons, there’s no doubt about that. I asked myself what were the things that appear inexplicable and are used to support religious beliefs.” Then Crick sought toshow that those things have a purely material foundation. In the same vein, physicist Steven Weinberg confesses that the hope science will liberate people from religion “is one of the things that in fact has driven me in my life.”

The adversaries of religion, like Crick, Weinberg, Dawkins, and Dennett, frequently conflate procedural atheism with philosophical atheism. They pretend that because God cannot be discovered through science, God cannot be discovered at all. Here is a classic statement from biologist Will Provine: “Modern science directly implies that the world is organized strictly in accordance with deterministic principles or chance. There are no purposive principles whatsoever in nature. There are no gods and no designing forces rationally detectable.” Provine makes it sound like this is one of modern science’s great discoveries, whereas it is modern science’s operating premise. Provine assumes without evidence that scientific knowledge is the only kind of knowledge, and that it gives us true and full access to reality.

Are these assumptions valid? I will examine the second one in a subsequent chapter. But consider the first premise, that scientific knowledge is the only kind of knowledge. Physicist John Polkinghorne provides the following example. If you were to ask a scientist, “Why is that water boiling?” he or she would answer in terms of molecules and temperatures. But there is a second explanation: the water is boiling because I want to have a cup of tea. This second explanation is a perfectly valid description of reality, yet it is ignored or avoided by the scientific account. The reason for this, mathematician Roger Penrose writes, is that science is incapable of answering questions about the nature or purpose of reality. Science merely tries to answer the question, “How does it behave?” So science does not even claim to be a full description of reality, only of one aspect of reality.