American philosopher Dennett explains why he called one of his books Darwin's Dangerous Idea, and why many of Darwin's contemporaries, in particular, considered Darwin's theory of evolution to be dangerous. He goes on to deal with the question of consciousness (i.e., is the consciousness/soul distinct from the body), talking about Darwin's rejection of the soul and the possible origins and psychological purposes of a belief in an immaterial soul.

Next, he talks about his Christian upbringing and how he became an atheist. He goes on to ask why it is thought rude to criticise religious belief, and suggests that it is due to the influential status of the religions in question. He finishes by wondering whether we could live effectively in a post-theistic world.