Alzheimer’s crept up on Iris Murdoch slowly. Friends started noticing that she was not understanding questions they asked or remembering things that they had done together.

John Bayley, her husband, was surprised one day by something she said about the novel she was writing, Jackson’s Dilemma, which proved to be her last. In the past she had often remarked that she was stuck, but this time she said: “It’s this man Jackson. I can’t make out who he is or what he’s doing.” “Perhaps he’ll turn out to be a woman,” Bayley said, trying to make a joke of it. She usually laughed, even at his feebler jokes, but now she looked solemn and puzzled. “I don’t think that he’s been born yet,” she said.

Nevertheless she finished the book and it was published. It got good reviews, but when Bayley read these out to her she did not seem to understand them.

Bayley recorded in his book Iris that after a while readers started writing in, pointing out small errors and inconsistencies they had found in the book. They were friendly letters, obviously from fans who had begun to worry. Indeed, when a year or two ago I happened to make a close comparison between Jackson’s Dilemma and the sparkling novels that she had written before. It was clear that her mind had actually lost its brightness. The story flowed on, but it lacked all edge and sharpness. When Bayley asked her about her ideas for a new novel, all she could say was that she had ideas but that they would not come together.

As things became worse Bayley looked after her very tenderly, without hesitating to get cross with her sometimes — partly because he thought that it was good for her and partly because he really was cross.

But when I was at their house with them not long before she died she just drifted about while we talked, smiling sweetly and saying nothing. So this remarkable writer fell into silence. It was one of the most tragic things I have seen — to watch the marvellous mind of a woman I was deeply fond of go blank.

Derwent May writes The Times’ Nature Notes and Feather Report

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