On the last weekend of our children’s summer vacation, we adopted an 8-year-old rat terrier named Foster from another household. I’m trying, from force of habit, to fix my story in time and place, although chronology, as far as I can tell, doesn’t mean very much to a rat terrier.

It seems that regardless of what the calendar might say — even if the page reads September or even March — a terrier lives his life as a summer life, a continual season of leisure, expectancy and tropical adventure.

Foster’s known biography began at the doorstep of a local cleric, who sheltered the stray until he could be adopted by our friend Sonny, who kept him for a number of years before deciding that upcoming travels made dog ownership impractical.

Foster, so named because he’s passed his years as a canine foster child, now lives under our roof, costing a few vet bills and the price of dog food, but saving us the expense of alarm clocks, which are no longer necessary.

Our pet rises at dawn and begins angling for his walk, bouncing like a pogo stick on his hind legs as he jumps upward to connect with his leash. He is 12 pounds and, when excited, looks like an Easter ham touched by divine levitation.

Foster is curious about everything but the morning paper, which he blissfully ignores on his way down the driveway. This is supremely insulting to the journalist at the other end of the leash, but I’ve resigned myself to our dog’s complete ambivalence about the ebb and flow of the stock market, the hot or cold of international diplomacy, or the football rankings within the SEC.

Foster reads his news through his nose instead, sniffing every shrub and garbage can to gauge the health of the world. With a lawyer’s love of precedent, he’s anxious to know what sort of fellow traveler has crossed the path before him, bending his snout to the ground to grasp the aroma of long-gone canines, cats or rodents.

He thoughtfully ponders the evidence, his face adopting the sage expression of a judge pronouncing sentence, before lifting his leg to leave his own message for posterity. In this way, Foster writes himself into our neighborhood every day, owning the landscape as confidently as those of us who have had to claim a place on the block by paying a mortgage.

He is madly in love with Harper Lee, a golden retriever down the street who, unlike the author who inspired her name, is friendly and open and obliging of his advances. Harper is three times bigger than Foster, but he sees this as no impediment to courtship, being an inveterate romantic who embraces lost causes. Among his quixotic passions is a running campaign against squirrels, who are much too fast for him and always will be.

Optimism, sometimes rewarded and sometimes not, is what gets Foster up in the morning. I’m told that over time, dogs become more like their owners. But I am wondering, and also wishing, if over time I might become more like Foster.