The story starts at the end.

We are sitting on a bench, holding hands. We've been sitting on benches holding hands for years and years. It doesn't matter what city we are sitting in today, there have been plenty of cities. Our children might be in this city, our grandchildren might be in this city.

Or they aren't. Chances are we know someone in the city we are in today, someone said, "Oh, take an afternoon walk and we'll see you for dinner." Really, is there anywhere in the world that you can imagine where we don't know people?

I can't remember the first bench we sat on together, if it was in Chicago or New York or Tel Aviv or Buenos Aires or Dublin or Rome or Moscow. It seems as if you are the only person I ever sat on benches with holding hands. It isn't true, of course, but it seems that way by now.