In his famous essay "Charles Dickens" (1939), George Orwell maintained that, 70 years after Dickens's death, a comedian who went on to a music-hall stage and imitated one of his major characters would stand a fair chance of having his imitation recognized. Another 70 years later this rule probably still applies: As recently as the late 1980s one of the U.K.'s senior anti-Conservative politicians could be found gamely comparing Mrs. Thatcher to Miss Havisham, on the grounds that the former doggedly presided over an economy that, like the latter's wedding cake, had long since crumbled to dust.

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