Within the frame of materialism, God does not exist, and if you remain within that frame (as our co-host did until the age of 26) then New Atheism is a compelling and comfortable philosophy. If there’s no evidence for it, no scientific backing for it, it’s meaningless because it can’t affect you.

But as you grow older you start to recognise that materialism is its own ism. It’s a model that is useful, so that gives it a powerful claim on our attention, but you start to notice its holes. Epistemology, for example - the question of how we know we know things - is something that materialists tend to ignore, but there is plenty of evidence that our senses are not reliable. Think of how a straight stick looks bent when you put it in a glass of water, and the implications of this. We have to accept that our knowledge of an object is separate from ...