Tim Dowling: I'm on my friend's 60th birthday march, but he'll have to remain anonymous

I'm at a 60th birthday celebration in the country, on a walk that will turn out to be 8½ miles long. The thirty or so guests meander in single file along a hedge, a glimpse of the sea visible in a hollow between rolling hills. The day is clear and warm.

There is some sort of guide, a man I don't know. He has a stick, a tweed jacket full of moth holes, and looks like someone who knows local affairs well. He stops to point things out, but I'm still near the bottom, and by the time I get there the conference is usually over.

In an effort to catch up my delay, I pass my friend Stefi, who carries his dog in a sling, like a baby.

"She has just had surgery", he says.

"I'm not judging", I say.

The group regroups while everyone waits to clear an amount , and scatters again as the road descends a steep incline.

"They say you burn more calories going down than going up," I say to Steve. He looks at me.

"How could that be true? Stefi said.

"That's right," I said. "I heard it on a show."

"OK", said Stefi, "explain to me how it works." It's hard: I listened closely enough to the show to believe the claim, but not enough to be able to defend it.

"You know, the muscles", I said.

“That must be bullshit,” he said.

When the path goes uphill again , I leave Stefi behind me . I feel bad because he's crippled by the dog strapped to his chest, but I need to find someone more gullible to talk to.

Au top of the hill, near the intersection of two hedges, our guide talks about the castle. I miss the beginning, only hearing information about its ancient provenance, historical significance, and strategic importance. People start mumbling among themselves. Finally, someone in the back raises a hesitant hand.

"Where is it?" she asks.

"Where's what?" says our guide.

"The castle", she says.

"It's here", says he, using his stick to point at the hedge, and the grass, and the other hedge.

Everyone looks around, thinking the same thing: there is nothing.

"It's not like a castle on television", explains the guide. "With walls, drawbridges and turrets."

"Is it a castle of the mind?" says our host, the man whose birthday it is.

"You must understand", says the guide. "They built this thing without machines, without shovels."

"Just with their imagination," I said quietly. The group advances, bewildered.

After lunch, I catch up with my wife on a downward slope. She's talking to our friend Miranda, and they're walking really fast.

"They say you burn more calories going down," Miranda says.

"Yeah, I heard that," my wife says.

"That sounds like bullshit," I say.

< p class="dcr-kpil6a">"No, it was on Radio 4", says my wife.

"I listened to the same thing!" Miranda said.

"Me too," I said, "but, I mean, how could that even...?" My words get lost in the breeze as they walk past me.

Gathering for dinner later, the thirty or so friends stand with glasses of champagne at hand as host - the man whose 60th birthday it is - gives a short speech. The first part is largely devoted to thanks, and the last part to the introduction of the next speaker: me. I have a few A4 sheets clasped in my left hand, covered in erasures. Most of my recent reviews have taken the form of reflections.

The man whose birthday it is suddenly declares that in all the years I've been writing my column , he was never named there. He draws up a long list of people present who have been named, some of them more than once. While he, he says, only appeared twice, once as an anonymous, hard-of-hearing extra with no funny lines, and once as a minor character known only as Friend C.

I'm a bit stunned by this. I often worry about how people will feel about being named in the press, but I never give much thought to how they might feel about being left behind.

When the speeches are over and glasses have been raised to honor the man who turns 60, I'll find him to assure him it's nothing personal.

"It's just because you're...