Michael Erard's Babel No More is about these hyperpolyglots. It is not about concierges or mâitre d's who can charm guests in Japanese, English, and French, or about diplomats who get along without a translator in Moscow, Cairo, and Shanghai. Such people are strictly amateur compared to, say, Harold Williams, a New Zealander who attended the League of Nations and is said to have spoken comfortably to each delegate in the delegate's native tongue, or the American Kenneth Hale, who learned passable Finnish (one of about fifty languages he was reputed to speak convincingly) on a flight to Helsinki and allegedly learned Japanese after a single viewing of the Shogun miniseries.

The most famous hyperpolyglot is Giuseppe Mezzofanti, the nineteenth-century Bolognese cardinal who was reputed to speak between thirty and seventy languages, ranging from Chaldaean to Algonquin. He spoke them so well, and with such a feather-light foreign accent, according to his Irish biographer, that English visitors mistook him for their countryman Cardinal Charles Acton. (They also said he spoke as if reading from The Spectator.) His ability to learn a language in a matter of days or hours was so devilishly impressive that one suspects Mezzofanti pursued the cardinalate in part to shelter himself from accusations that he had bought the talent from Satan himself.

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This all suggests that there's no magic formula for language learning, or at least nothing that one can use purely through an act of will. You can't become Mezzofanti, in part because the traits are not generally voluntary and in part because even Mezzofanti wasn't Mezzofanti. There are learning techniques that sometimes work and sometimes don't; some say adding physical movement helps learning (Arguelles likes to run around and shout vocabulary words), and some suggest that zapping one's brain with electricity can boost memory. But for most of us, it's back to the flash cards, and to humiliating ourselves when we try to order in French restaurants.