Sir, Though often accused of changing his opinions, John Maynard Keynes almost certainly never said: “When the facts change, I change my mind. What do you do, sir?” (“An apt misquotation can reveal the greater truth”, John Kay, December 30.) However, his Cambridge contemporary, the noted economist Joan Robinson, records him as saying: “When someone persuades me that I am wrong, I change my mind. What do you do?”

Displaying a fine wit, Keynes wrote to The Economist in 1933 on the topic of the gold standard: “I apologise for occupying your space. But since there are people who deem it creditable if one does not change one’s mind, I should like to get what kudos I can from not having done so on this occasion!”

Dr John Doherty

Vienna, Austria

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