It's always struck me as a little odd that journalists proclaim to know what the nation is thinking, or feeling.

I often fall into this trap myself. I willingly concede that I lead something of a cloistered life and, because I don't have first-hand experience of some of the commonplace aspects of modern life, I am probably unqualified to discuss the tastes and passions of what I call "real people". For example, I've never been to a McDonald's or a Starbucks, I've never seen EastEnders or Star Wars, and I've never followed The X Factor, or indeed any reality show. But occasionally I see or read something that exposes my ignorance of a feature of popular culture that shocks even me.

Yesterday, the YouGov polling organisation presented their bi-annual index of Britain's most well-respected brands. Amazon came out top, Google was in second and the BBC iPlayer was in the bronze medal position. I looked down the chart and saw all the names I'd expect to see - Marks & Spencer, John Lewis, Heinz, Sony, Sainsbury's etc. But there, sandwiched (pun intended) between Channel 4 and Samsung is a brand of which I was almost completely unaware: Cathedral City.

My colleagues were astonished that I hadn't sampled the delights of this mass-produced brand of Cheddar cheese, but it's worse than that - I can only vaguely remember seeing it on a supermarket shelf and then only to wonder in passing which cathedral city it came from; and I've never seen the television advert, which is responsible for turning a moribund brand bought by the dairy products giant Dairy Crest in 1995 into "Britain's Favourite Cheese" (or at least that's what their own website says).

I have now seen the advert, which certainly rivals the John Lewis oeuvre for homely charm and sentimentality and I have discovered that the cheese is made in the Cornwall town of Davidstow, which is neither a city nor has a cathedral. It is a triumph of marketing, for sure, and it amazes me that people would feel so passionate about a make (not type) of cheese that they would score it higher than, say, Dyson or Waterstones. I always thought that one's preference for cheese would be about geography, taste and tradition rather than brands: you may prefer the rich smoothness of Cheddar to the chalky crumbliness of Lancashire, for example. Cheeses are rooted in their environment and the historic methods of fabrication.

Cathedral City is cheese. Just that. It doesn't really matter where it comes from, as long as it has the same dependable, homogenous quality. And nothing wrong with that, either, as long as this cleverly constructed marketing campaign doesn't genetically modify the landscape of British cheese. I have a fear of future generations naming their favourite cheeses: Stilton, Wensleydale, Cathedral City...

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