In the madness of late spring at San Marco Square in Venice, amid the hordes pouring in from land and sea, hard by the hissing espresso machines and sizzling panini presses of overpriced cafes, I found the still point of the turning world. I found it in the library.

It was 10 in the morning and I was standing, alone and enthralled, on the second floor balcony of the Biblioteca Nazionale Marciana. Across the Piazzetta rose the Doge’s Palace. At my feet, tourist insanity. At my back, an immense, hushed, empty reading room designed by Jacopo Sansovino and decorated by Titian and Veronese.