When my architect friend Westley visits Paris, he doesn't dawdle in the Louvre or climb the Eiffel Tower. Instead, he goes for a stroll. "I want to experience the city like the locals do," he once told me. "The idea of crowding around the Mona Lisa with a scrum of tourists just doesn't interest me." In other words, Westley is a boulevardier, a "flaneur," that great French word derived from the Old Norse verb "flana" or "to wander with no purpose."