Like most places the Selbys decide to visit, Greece is suffering some disruption at the moment, but we can cope as long as we have a bottle of retsina, a chunk of cheese and the sun cream. Oh, and thou beside me in the wilderness, obviously, I add to my husband, who is off to mow the lawn.

He leaves and I muse thoughtfully on what different people find essential for comfort. For me this means certain people, certain food, the piano, mascara (obviously). But why am I essential to Mrs Regular? I feel I make no difference, week on week, year on year. Weekly I suggest that if she waited, say, a fortnight before returning, it is almost certain that, still, nothing would change, so perhaps there is some benefit in giving it a try. But it seems I am as necessary to her as cheese is to me (I wouldn't die without it, but I'd spend a lot of time hanging around the fridge looking mournful.)

A moment later my husband reappears. It seems that rats have eaten through the ignition cable on the mower so the lawn cannot be mowed.

So, I say, meditating on Why Things Are Essential, you'll have to leave it.

I know, he frets mannishly, the grass will get really long.

A moment's silence hangs between us. I hesitate then, delicately, like one casting a morsel of rare steak into a pondful of sharks I say, 'And?'

It's obvious, he says patiently. Grass grows, deer move in, predators follow and soon there are lions under the trampoline and bears on the swing. Give nature a second and you're in Jurassic Park. You can't just leave grass.

Well, I say, we could give it a go.

We'll have to, he says, but don't blame me if something eats you the next time you get out of the car.

I'm unsurprised to find that Mrs Regular has booked the first appointment after my return. I can kind of see her point.

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