After some twenty-five years of running and writing about restaurants a few things have struck me as eternally true, no matter in what restaurant or in what country you find yourself. These truths, which I hope will make the backbone of a new science that I've christened 'gastronomics', may just help you to get more from your next restaurant visit. So with my tongue lightly in my cheek, here they are:

1. Distrust a menu which praises its own food. For example 'Tiny baby potatoes lovingly basted with melted butter and softly sprinkled with hand-chopped parsley' or 'succulent feuillettes of passionfruit smothered in a rich, creamy chocolate sauce' are danger signs. Treat this sort of thing with deep suspicion.

2. In amazingly trendy and fashionable restaurants the waiters and waitresses will have a higher opinion of their own celebrity than they will have of yours, and the chances are you'll be treated with all the disdain that they can muster.

3. Whenever a new food becomes fashionable it will appear with increasing frequency and will eventually find itself in inappropriate dishes as chefs attempt to be even more inventive. Thus goats cheese will soon be found in soups, sauces and desserts.

4. Perfectly agreeable dishes go out of fashion and become unavailable. Prawn cocktail and crepes suzettes, once the alpha and omega of any menu, have now gone the way of Neanderthal Man. The occasional attempts by innovative restaurateurs to re-introduce old favourites are rarely successful.

5. A good waiter has a mental to-do list of nine items. If your request for a jug of water is number ten, it will be forgotten.

6. The best-selling wines on a list will always be the second most expensive in any section of that list. Good sommeliers know this, and place the slow movers here.

7. When a table is booked for a number of more than ten people, the final number will never be the one booked for. It may be more or less, but never the number planned.

8. Extremes are unavoidable and inevitable. For instance once it has been established that vegetables should not be over-cooked, they will be invariably under-cooked.

9. Food fashion is ephemeral. When a cooking style such as 'nouvelle' finally found its way to small country hotel dining-rooms, it was time for a new 'nouvelle'. When tall food can be found all over the country you'll know it's days are numbered.

10. A new restaurant will always be full. This is because the search for the perfect meal is continual. Every newly opened restaurant is a ray of hope and it will be patronised until it proves itself to be otherwise.

11. A place-setting with a napkin arranged origami-like into a clam-shell or a rose, promises a formality unlikely to be mirrored in the food. It's an image indelibly linked in my mind to half a grapefruit with a cherry in the middle, brown Windsor soup and the smell of boiled cabbage.

12. Dishes that arrive covered, and are unveiled with all the pomp of a conjuror removing a rabbit from a hat, will often disappoint.