Just call me the Absent-Minded Professor.

I’ve always been a bit scatterbrained when it comes to walking on the street. I’ll cross against the light as cars whiz by me, bump into strangers while my head is buried in a book or wander for blocks in the wrong direction because I’m not paying attention.

I outdid myself today by walking straight into the raised rear door of a parked Honda hatchback as I was daydreaming on my way to class. I went down with a thud, like a boxer decked by a vicious hook, and remained dazed for about 30 seconds. When I looked down at the ground, I saw a pool of blood that had formed from the deep gash in my forehead.

I stopped at my office and got a paper towel to press against the wound. Our administrative assistant Amber played Florence Nightingale, finding a cotton swap and an antiseptic solution to clean the cut. We couldn’t find a Band-Aid, so I rushed off to class with a piece of bloody paper stuck to my head.

When my students saw me, they oohed and aahed and acted like rubberneckers at a car crash. I tried to explain what happened, but they seem baffled. No wonder. In any language, walking blindly into a car door is inexplicable.