You stand in the crowded BART car, pressed in on all sides. You stare ahead, eyes unfocused, just waiting for the train to arrive at your station. Finally, you hear the train announcement: “Montgomery Street. Montgomery Street Station!” You lean down to pick up your backpack and see that someone has grabbed the other strap.

You look at the man. He’s seated next to the door, inappropriately in a “reserved for handicapped and elderly” seat, grubbily dressed in a long black coat. You think how strange it is to be dressed this way, today is predicted to be another very hot September day.

You say to him, “Sorry, this is MY backpack,” and pull it away from him, the other strap slipping out of his fist. His hand opens and you see how slimy and dirty and vile, how repugnant it is. You shudder, thinking how disgusting it is to have his filth on your backpack. You look at the gunk left on the strap. It’s shiny like the trail of a slug or snail but thicker and glutinous, a dirty color like his hand. You glare at him for a second as you move your backpack to the side away from him and join the crowd leaving the car onto the platform. You take the escalator to the street level, the south side of Market Street, and start to walk the five blocks to the UC Berkeley Art and Design Center for your first class of the day.

As you pass the Walgreens at Third and Market you decide to get something to clean the slimy strap on your backpack. You enter the store and see that there’s an information counter.

“Excuse me, I need something to clean off and sanitize the strap on my backpack. What can you recommend?”

The girl at the counter smiles and it seems genuine, whatever that means. “We have cleaning supplies on J-3. I’m sure you’ll find what you need there.”

You return her smile and say “Thanks” as you step away and see that aisle J is the second one over and J-3 is the third section back. This is the first time you’ve ever shopped in this Walgreens and you’re impressed by how huge it is. Section J-3 has an overwhelming number of different kinds of cleaning supplies on both sides of the aisle. Fortunately there’s a stock clerk refilling the shelves.

You walk over to him. “Excuse me, I got some grunge on the strap on my backpack, and I’m looking for something to clean and sanitize it. What might be a good choice?”

He smiles, very much like the girl at the information counter.

“There are some cleaning and sanitizing wipes that are popular over here. I’m always restocking this section. This brand seems to be the fastest moving.”

You reply, “Thanks!” as you check the plastic tube. You can just picture a TV pitchman shouting ‘Cleans! Removes Grunge! Freshens! Sanitizes!’ as you read the directions. Seems simple enough. Sort of expensive, $3.99 for 35 wipes, but you need them. You carry the package of wipes to the registers at the front of the store and make your purchase.

You get to class about 15 minutes before starting time and open the package of wipes. They aren’t very large, but they seem like they’ll work just fine.  It takes six of them to remove the grunge from the strap, plus two extra to make sure it’s sanitized and one extra to hold the wad of filthy wipes. You walk to the front of the room and toss them into the wastebasket. You return to your seat as your first class of the day begins.

Your last class is over at 3:45 and you’re on your way back to Walnut Creek. You don’t see that repugnant man on the street to the BART station, on the station platform, or in the train. Any thought about your morning experience on BART fades away.

You’re watching the ten o’clock news that night. The lead story is about a man who either fell or was pushed off the BART platform at the Montgomery Street station. He was hit by a train pulling into the station and died of his injuries. They describe him as wearing a long black coat. You wonder, could he be that repugnant man who grabbed your backpack? The story continues. They are looking for witnesses who might have seen this man on the platform or on one of the trains.

You have a dilemma. Should you go to the San Francisco police tomorrow and report what happened on the train? How much time would that take? Certainly too much time. You have classes all day. You saw him on the train, you didn’t see if he got out of his seat or left the car. You didn’t see him on the platform. You didn’t see or hear anything that could be of use to the police.

You wonder about the man. He looked homeless. Was he high on booze or drugs? How did he get into BART? He must have had a ticket. BART is expensive; where did he get the money to buy a ticket? Why would he waste money on a BART ticket? Why was he on the BART train from Walnut Creek? Where did he get on? Where was he going? Why did he grab the strap of your backpack? Was he trying to steal it? Did he think it was his backpack? His coat was grubby, but you didn’t smell any body odor. You’ve seen lots of other homeless men and women sitting or lying on the sidewalks in San Francisco and they all had a bad, sometimes overpowering, body odor. You think about the man. What happened that made him homeless? Where did he live? Did he have a family? Did he lose his job? Did he lose his home? Was he a veteran returned from the war? Could he have been someone like you?

You remember the long black coat he was wearing, and his grungy hand. But what did he look like? You stared at him for a second or two, but the only things you can remember are his long black coat, his grungy hand, and the slime he got on the strap of your backpack. You realize that you don’t know what his face, his eyes, his nose, his mouth, his hair, looked like. The only thing you know is that he invaded your space and privacy by grabbing your backpack strap. To you he was just another faceless homeless person, just like he was to everyone else who saw the man on the train, saw him on the platform, saw him when he fell or was pushed onto the tracks. You’re not even sure it was the same man they talked about on the TV news. What you remember is that the man on the BART train was repugnant.

You decide the man in the black coat isn’t your problem. It’s more comfortable to let repugnance overcome responsibility. That bothers you, but only for a moment. The weather news comes on. It’s going to be another hot September day in the city tomorrow.