He lifts the saw and skids to a stop. He carefully cuts two circular holes in the ice about fourteen feet part and three feet in diameter. He sets the saw down and lowers himself into one hole, takes a breath, and swims under the ice to the other hole. Climbing out, he picks up the saw, restarts it, and, squatting again, zooms back to the shore. He waves cheerfully at the camera and disappears into the brush.

That video clip popped up recently on my Facebook page. I can’t find out where it was shot, but I’m pretty sure it wasn’t Vermont; we have snow on our ice here. I’m guessing Eastern Europe. The skate-shod swimmer looks as though he was weaned on pilsener and kishka. Whatever his provenance, he’s got a lot of what Finns and some other northern Europeans call sisu.

If you look it up, you’ll find that sisu is Finnish in origin, though it’s used in other countries. The Russians who celebrate New Years Day by chopping holes in the frozen Volga and dipping for the newsreel cameras use the term for their tough-cookiness. But its original meaning refers to the ability of some folks to suck up whatever nature or their fellow men throw at them, and to persevere in its face. It was used a lot during the dramatic so-called Winter War of 1939-40, when the Soviet army invaded tiny Finland, and in weather that sometimes reached -45º Fahrenheit, found their adversaries far tougher – they fought on skis and even used reindeer to haul supplies – than the Germans they faced farther south. The defenders’ motto, in that bitter-cold darkness, was “Dying isn’t the worst thing that can happen.”

We have sayings similar to that right here in New England. Accustomed as we are to the apparent perversity of nature and her weather, we revive the old football slogan, “When the going gets tough, the tough get going!” Facing the perilous trek to the barn with the trash bin, or to get the car, I don microspikes for the ice, a Life Alert button for exigencies, and an over-the-ears tuque for the wind, muttering, “Suck it up, old-timer. Suck it up.” Even the dog, who never fails to join me, often walks comically on three legs.

We hear much talk in the various media about that poor, suffering rodent, Punxsutawney Phil; about still having half our wood and half our hay on Candlemas Day; and the fact that we’ve passed the middle of meteorological winter. We note that the sun brightens our afternoons much later than it did only a month ago, and that the worst of the cold is over (assuming it’s a normal winter). But we don’t often reckon with the fact that this second half of winter is for many people the worse. It seems to stretch out ahead of us almost to infinity, and what’s at the end of it? Mud season. It’s like the second half of a football game: You can tell by now who’s probably going to win, and you want it over. You’re tired and sore, and there’s just no way to make that clock go any faster. That’s when you have to remember: Suck it up. You got this.

Sucking it up is impractical for people who get depressed by the darkness and the cold. There are lots of things they could do to help, but the problem is the inability to get at them in the first place. For many of us in our sunset years it’s tempting to slide into inactivity and wait for the inevitable. Not a great idea.

The happiest old people I meet are in the park each afternoon with their dogs, tramping around in the snow and ice. I’ve had the incredible good fortune to be one of them. And I keep a calendar always on my desk, reminding me of the dates of things to look forward to: lunches with friends; storytelling gigs; the first dry roads of spring (a little silvery roadster lies waiting in the back of the barn); a reunion visit to my old school; fishing for big browns and rainbows in Montana in late summer; leading a tour of Scotland in September. Life is like a crowded elevator: It’s impossible to fall down.

In the quiet moments – and there are many – there’s the daily brain training of the Times crossword puzzle that gets tougher each day till Sunday. On the coldest days I feed my wood boiler every three hours to take the load off the oil furnace. I can tell it’s going to be a good day if in the early morning I open the firebox door and find a still-glowing bed of coals waiting to be fed. The aroma of coffee drifts through the house, inspiring dreams of ham and eggs; and on the coldest days the sun climbs over the ridge to the east ever earlier and ever farther north. After breakfast, as the sun finds its way around to the big south window, the dog will lie in my lap as I nurse a second cup, read a little, and schedule my day. It’s a long way from fighting the Russkis in Karelia and jumping through holes in the river ice, but it’ll do. It’ll do.