Last week John Cleese brought me down from Edinburgh. I did the driving, he did the directions. “Enter the roundabout,” he'd say. “Take the third exit.” That sort of thing. And then, somewhere near Sheffield, he said this: “Beaver right.” “Beaver?” said my wife, who was also in the car, along with me and John Cleese. “What the hell is beaver?” I was puzzled, too. I'm not really the Top Gear type, but if Jeremy Clarkson and his friends were frequently using the word “beaver” I felt I'd have known about it. So probably, we decided, it was an Americanism, referring to some sort of shimmy. Cleese didn't correct us. “Take the motorway,” he droned. “In 200 metres, go left.” He's a dull chap.

It is my second sat-nav, the John Cleese one. I added the Cleese voice myself, in a shameless novelty purchase. The actual machine was a Christmas present, and it is made by a Leading Brand. It was intended to replace another sat-nav that I had bought myself, about a year ago. I had been about to head off to some remote bit of Wales, and I saw it on sale for virtually nothing. That one was not made by a Leading Brand.

“Don't buy it,” my friend Matt had advised. “It'll be rubbish and you'll get lost. Spend a bit more. Get the Leading Brand one.” “Pshaw!” I had retorted, or words to that effect. “You are a marketing stooge. Rubbish how? Either it works, or it doesn't.” Matt, who is a proper car person, and would have known what “beaver” meant in an instant, let me get away with this. He knew he would have the last laugh. True enough, I called him late that night, from within an actual, honest-to-God field, into which I had turned at some speed from the motorway.

“This thing is a heap of s***,” I told him. “It could have killed me.” “At the next junction,” intoned Matt, “chuck your inferior sat-nav into the gutter.”

For the sat-nav, ubiquity is just around the corner. I can imagine children, in a couple of decades, flatly refusing to believe that one used to be expected to get from place to place simply by knowing the way, like an animal. By then, surely, we'll probably have voices telling us to do all sorts of things we currently remember to do by ourselves. “After wiping, use the handle to flush.” “In three seconds' time, breathe.” Perhaps that lucky “mind the gap” woman could do them, too.

But back to this beaver. A few years ago I'd probably have dwelled upon it, or asked people about it, or woken up, suddenly realising, in the middle of the night. As it was, I Googled it. Then I called my wife.

“It's a joke,” I explained. “It's not an instruction at all. He's just said “bear left”, which sounds a bit like he's saying there's a bear on the left. So then he says “beaver, right” so as to suggest there is a beaver in the picture, too.” “That's the weirdest joke I've ever heard,” said my wife.

Both of us, I think, felt that Cleese had let us down. “After this joke,” he really should have said, “remember to laugh.”

Times Recommends

• In the real world, the public sector must pay
• Playing politics in a land of double Dutch
• Be like the plinth people: not set in stone