Exceptions are the possessives of ancient proper names ending in -es and -is, the possessive Jesus', and such forms as for conscience' sake, for righteousness' sake. But such forms as Moses' Laws, Isis' temple are commonly replaced by: - the laws of Moses; - the temple of Isis.
Some years ago, when the heir to the throne of England was a child, I noticed a headline in the Times about Bonnie Prince Charlie: "CHARLES' TONSILS OUT." Immediately Rule 1 leapt to mind.
1. Form the possessive singular of nouns by adding 's. Follow this rule whatever the final consonant. Thus write,
the witch's malice
Clearly, Will Strunk had foreseen, as far back as 1918, the dangerous tonsillectomy of a prince, in which the surgeon removes the tonsils and the Times copy desk removes the final s. He started his book with it. I commend Rule 1 to the Times, and I trust that Charles's throat, not Charles' throat, is in fine shape today.
Style rules of this sort are, of course, somewhat a matter of individual preference, and even the established rules of grammar are open to challenge. Professor Strunk, although one of the most inflexible and choosy of men, was quick to acknowledge the fallacy of inflexibility and the danger of doctrine. "It is an old observation," he wrote, "that the best writers sometimes disregard the rules of rhetoric. When they do so, however, the reader will usually find in the sentence some compensating merit, attained at the cost of the violation. Unless he is certain of doing as well, he will probably do best to follow the rules."
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