The two boys crossing the bridge in front of me are obviously brothers, one of them perhaps ten years old, the other twenty. The small one, very agitated, is talking on and on to the other, and the older one is answering in a deliberate, fatherly way, explaining things. They are speaking Spanish; I don’t understand a word, but their intonation makes them brothers, and their intonation lets you recognize questions and answers. And suddenly they are speaking Swiss German, completely without accents. They switch languages without noticing it themselves at all, and now that they’re speaking Swiss German, they suddenly no longer look like Spaniards. It’s a lovely conversation between the knowledgeable older brother and the questioning younger one. I would have liked to continue listening, but then they speak Spanish again. . .