It's day five of our planned month-long stay à Paris, late April through most of May. My wife is here for workfor me, it's strictly for pleasureand we're enjoying Paris's rich, sensual goodness: food, museums, architecture, coffee, people, food. And yet, earlier today, when we were out for a walkwe've been walking close to 10 miles each day, exploring the cityI realized that my life here has been missing something important.