Ian McEwan has frequently expressed his views on subjects beyond literature. He was not in favour of Brexit. He was not in favour of boycotting Israel, but does not approve of the current Israeli government. He is worried about the climate and believes that a man is someone born with a penis. Over the past twenty years, he has aired these positions in his fiction. In Saturday (2005), he channelled his distaste for the protests against the invasion of Iraq. The Cockroach (2019) is a not at all veiled satire of Brexit. What We Can Know, his nineteenth novel, is an enjoyable work of speculative fiction that addresses topics such as climate change and AI.

The novel opens in 2119. After failing for decades to address the looming catastrophe of climate change (known as ‘the Derangement’), humanity suffered a nuclear war triggered by AI. This led to a series of disastrous floods (‘the Inundation’). The UK has become an ‘archipelago republic’. The first half of the novel is narrated by Tom Metcalfe, an academic at the University of the South Downs, who teaches a course on literature and history and specialises in the poet Francis Blundy, a respected member of the early 21st-century literary establishment. Blundy was not shy with his opinions on the great issues of the day. His position on Russia’s invasion of the Crimea proved shrewd: ‘Francis insisted that the Russians should be forced to withdraw, otherwise they would be tempted to greater aggression.’ His scepticism about man-made climate change – ‘fashionable nonsense!’ – has proved to be less prescient.

Tom sifts through the Blundy archive, searching for traces of the poet’s most famous work, ‘A Corona for Vivien’, in his emails, letters and other writings. No copy of it appears to have survived. The poem, written in an archaic style, comprised a sequence of sonnets (fifteen in this case),