What We Can Know

What We Can Know is the 18th novel by author Ian McEwan, published in 2025 by Jonathan Cape. The novel is set almost a century in the future, in 2119, in a UK partially submerged by rising seas, and is centred on Tom Metcalfe, an academic at the fictional University of the South Downs, who is investigating a lost poem, read aloud at a party in 2014.

McEwan has described the book as a work of science fiction "without the science." In the book, people in 2119 call the first half of the 21st century "the Derangement" because everyone knew about climate change but failed to act.

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