Last night I attended a friend’s birthday dinner in Central Park, at Sheep Meadow Cafe. I think I drank too much. At one point, head spinning, I went off in search of fireflies. I found a few in an unlit field. Watching them I realized for the first time that they don’t flicker on and off but dive, again and again, into something dark. We see them as they surface and turn and dive back down into the darkness.