Here's the plan to save our small shops, Ken

He was talking about the seven ages of man, but his words could soon apply to London retailing as well. In modern Britain, all the world's a shop, and all the men and women merely shoppers.

And last week's interim report by the Competition Commission was, it turned out, an interim stage in the demise of the small shop. An inquiry into the supermarkets' dominance used a questionable mix of indicators to argue there wasn't really a problem. An inquiry that some saw as the last chance to limit the supermarkets' growth recommended allowing even more of them.

London will not be fun in the seventh age of retail, when the number of small grocery shops becomes too few to sustain an independent distribution system and when every food retailer, save a handful of bourgeois gastro outlets, belongs to one of four bland companies. Sans teeth, sans taste.

London will not be fun when every suburban restaurant is a chain, when the only difference is what order the Prets a Manger, the Zizzi Pizzas and the Chez Gerards come in on your particular high street. Their food is fine, I hear you say. But it isn't, and it's a sign of our low standards that so many of us think it is. Any multiple replaces the rule of the chef and the high-quality supplier with the rule of the head-office accountant and the industrial caterer.

Yet if the Competition Commission has failed us, we simply have to look for other ways to protect that much-talked-about, but seldom enforced, London thing: diversity. Sub-post offices are often the key to the viability of a shopping parade, not to mention essential services in their own right - but they're closing at frightening rates for lack of government subsidy.

Maybe Ken could subsidise post offices instead of subsidising yobbish teenagers to vandalise the buses. Maybe, rather than lunatic schemes to socially engineer the London cab trade, City Hall could support our mainly ethnic-minority small grocers, training them in how to stock a better range of goods and present their wares more attractively.

But the idea I like best is from the Green assembly member, Jenny Jones, who suggests that just as all new residential developments are obliged to include a proportion of "affordable housing," so should the developers of new offices, apartment blocks and shopping centres be forced to provide "affordable retail" - shop and restaurant space with rents non-chains can afford.

I love the thought that instead of the usual shiny marketing men's concept outlets - the kind of places that all sell the same five main courses - we might get a new butcher, or a greasy spoon, or somewhere that will sell you a single nail in a twist of paper. And it's something the Mayor could do, pretty much overnight. Any takers?