An upstairs room in a north London public library. I was teaching ‘Introduction to Contemporary Poetry’ to a class of twelve adults, and we’d been going for about twenty minutes. They were all new to poetry, no one wanted to talk, and the atmosphere was sticky. I thumbed Staying Alive – real poems for unreal times, the anthology I use as a set text, and it fell open at Seamus Heaney’s ‘Postscript’. I asked if anyone would like to read it aloud. Doreen mustered her confidence, cleared her throat, and kindly volunteered.