Every age has its apocalypse. Nuclear annihilation felt round the corner in my early teens. I assumed an early explosive death very probable. I knew people who built bunkers in their gardens and stocked them with tins of Campbell’s soups, sardines and baked beans.

Long before I was aware of that particular Armageddon, I expected more individual destruction in the manner described by Bunyan in The Pilgrim’s Progress, with which I began this book. But Bunyan, though never completely superseded – his visions of guilt and shame in the trek to the Celestial City were too vigorous – diminished during my teen years. His severe monotheism was giving place to a (pubescent?) pagan enthusiasm for green leaves and fields. I chose as my form prize at boarding school (which couldn’t have been all bad) The Collected Poems of Dylan Thomas.