How did belief in God, once everyone’s obvious and immediate default position, become, for so many in the West, “intuitively impossible”? In Unbelievers: An Emotional History of Doubt (William Collins, £20; Tablet price £18), Alec Ryrie disputes the standard answer. Atheism, he argues, long predated the cerebrations of Enlightenment intellectuals – as an inarticulate rage against moral authority. The “atheist” (that term was an insult equivalent to “fascist” today) did indeed tend to be a libertine and wastrel, often exemplified in the stock villain of Renaissance plays. Ryrie illuminatingly portrays how, once it asserted its own ethical principles, atheism began to undermine religion, which was ultimately “swallowed” by morality.