In artful boasting, one states all the information necessary to impress people, but keeps the facts decently clothed in the language of humility. Useful approaches include Disbelief, Fear and Manic Elation. For some reason, these are considered to be more attractive human emotions than justifiable pride or self-satisfaction. Probably because they are not as much fun.

Judith Martin (b. 1938) American author, journalist, etiquette expert [a.k.a. Miss Manners]

“Miss Manners,” syndicated column (1979-11-24)
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Collected in Miss Manners’ Guide to Excruciatingly Correct Behavior, Part 3 "Basic Civilization," "Social Intercourse" (1983).