I have to stop walking down dark streets at night, because the sidewalks in this town are notoriously uneven, and just now I took a really nasty fall. I am never been more frightened, in a right-in-front-of-you sense, than when I trip or lose my balance. It introduces you to your mortality in no uncertain terms, especially if, like me, you weigh a lot; it shakes me something fierce. In some ways it's worse when someone's around: an older man was not too far behind me when it happened, and offered help, but I'm useless when I'm panicking; it takes a minute or so to regain my senses. In this case, it was triggered by a simple question: "Did you break anything?" I didn't, thankfully. But already I am getting twinges in joints that normally don't consciously register. I hope it doesn't stick around.