In my seven decades on this planet, I have learned a lot about dogs. I’ve written books about dogs. So when a little dog showed up on my porch a couple of weeks ago, starving and thirsty and shivering in the cold, I immediately made some pretty astute deductions.

The dog was a gray schnauzer that I judged to be about two years old. He looked sloppy-shaggy, like schnauzers all look: canine Albert Einsteins who just rolled out of bed. He answered to no typical dog names, or variations of typical dog names, so I figured he probably had a very weird name, possibly a foreign-language-type name, like Horst or Pasquale.

I called him Crenshaw. I liked the irony; the name conferred a supercilious dignity he did not have. Crenshaw was a nice dog, affectionate to people, welcoming of other animals, except for Buster, the stray cat who lives with me part time now. It was odd: almost as if the two knew and disliked each other. I attributed it to interspecies rivalry; no animal wants a new, larger arrival to reduce him from gamma to delta status. I am very intuitive about this sort of thing.

When Crenshaw barked it was a high-pitched shriek, which as an expert I recognized as a classic sign of stress. I decided not to discommode him further on walks by abruptly bringing him out into the same car-whizzing streets that had so shivered and terrified him, so when we went outside it was through the back door into a warren of unthreatening urban alleyways.

I am not a dognapper, and I knew someone owned him, but it did occur to me, briefly — very briefly and innocently — as someone who has an elderly dog with some concerning health problems, that it would not be the worst thing in the world if Crenshaw wound up with me. He liked sitting on laps. He appreciated affection. He was housebroken. And he had pathos, which led me to conclude, possibly self-servingly, that he was probably mistreated and needed to be saved from the hellhole he’d come from.

When I left him alone in the house, he would begin to keen and shriek disconsolately. When I returned he was still shrieking, but staring down into the basement so intently that he barely knew I’d come up behind him. He was upset, and blaming the basement. Something bad had happened to him in a basement, I concluded. A dog-torture dungeon? Perhaps it was my solemn duty to keep him, and love him as he had evidently never been loved, for many, many years to come.

Still, I had advertised in lost-dog sites. And after three days, there was a hit. It was definitive.

It turns out I had made a few minor miscalculations. Crenshaw’s name was not Horst or Pasquale, but Cooper, and he was very American. He didn’t respond to his name because he was way older than I thought, and almost totally deaf. He shrieked because high-pitched sounds were the only things he could hear, and if you are a dog you want to hear your own bark. Deafness can be disorienting to a dog: You might, for example, decide that something threatening is in a basement, something you fear but cannot hear, so you yell at it to keep it at bay.

I had made a tactical error in not taking Cooper into the streets because if I had, he likely would have turned left, walked exactly one block, and gone home. Cooper had wandered from his house when a neighbor had been deputized to look after him, and he roamed aimlessly for a while. He and Buster disliked each other because, during their days on the streets, they had likely been in competition for food scraps. Cooper lived with a lovely lady who did not have a dog dungeon and whom Cooper joyfully ran to when we delivered him, deafly shrieking, as was his custom, and wagging and filled with euphoria, instantly and understandably forgetting the clueless idiot in whose home he’d been trapped for three days.

It all worked out perfectly. I am really happy, sort of.

Email Gene Weingarten at weingarten@washpost.com. Find chats and updates at washingtonpost.com/magazine.

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