It is amusing to observe the “it wouldn't happen here” stance that the British have adopted towards the Austrians over the Fritzl case, as if we ourselves lived in some perfect, open, exemplary society.

Ah, this terrible cellar story has happened because Austria is a society full of suppressed secrets, we cry. You wouldn't get that happening here, we say, as if suddenly converted to some evangelical belief in modern communality, UK-style.

With a certain amount of justification. Most of us are not only aware of our neighbours' ages, occupations, interests, alcohol consumption, political leanings, choice of car, children's manners and holiday destinations, but we also probably know more than we'd like to about their sex life: either because they've betrayed it at a dinner party, or because one of them has confided over coffee. The same goes, largely, for workmates. I'm generalising here, but you get my point: in this emotionally liberated age, and on a very crowded little island, there are far fewer secrets than there used to be. Privacy is for a bygone age. We like to think there is very little that we do not know about our friends and family - about their pleasures, their sorrows and their comings and goings. And in an age that is also based on conspicuous consumption, we can daily inspect the manner in which they spend their money: the house extensions, the marque of car, the clothes, the children's schooling.

Sometimes it is as if the restrained, deeply private family life I remember as a child has been turned inside out: instead of living quietly within four walls, the whole emphasis of domestic life is on public display.

There is one screaming exception to all this openness, and it is salary. The one thing that the British do not share with friends, neighbours or family - and sometimes even spouses - is the size of their income. To ask what someone else earns, or indeed to declare one's own salary, is somehow indecent - certainly on a par to confessing to wife swapping. In matters fiscal, few secretive Austrians have anything on us.

We are encouraged to get an impression from the way people choose to live - hence the three foreign holidays a year etc - but we must never ask, and never volunteer, hard figures. Salaries are to 21st- century middle-class Brits what sex was to their Victorian equivalent: a subject that did not exist in polite society.

Class, naturally, is everything to do with it. Among the vulgar rich and the very poor, there is no taboo. The very rich, being these days footballers or entrepreneurs or corporate bosses, are forced into transparency by rich lists or public accounting. The poor ditto, because they are homogenised by identical welfare payments. Or because they drive buses that proclaim on the back: earn £18,000 a year driving this bus (and - in small print - struggle to bring up a family, what with the price of food it is now).

And so the middle class grimly hang on to their omertà, because it is a sign of their respectability. In Britain, income remains permeated with old-fashioned snobbery. Even aristocrats, asset-rich paupers, declare themselves the new poor in order to distinguish themselves from lottery winners. Meanwhile, in other, freer, societies in the world - like China - the middle classes reveal their salaries as freely as they tell you their children's names.

Clearly, such hang-ups as Britain has are anachronistic, especially right now. There is something ludicrous about being in the middle of a credit crunch, an economic downturn, a housing slump, a mortgage drought and a bid for world domination by Tesco, and yet not be able to explain precisely why one is so totally, utterly, heart-breakingly broke.

The debate about salary reticence was sparked by a survey from a recruiting company that claimed that two thirds of workers would be happy to tell colleagues what they earned, in the selfless belief that it would help to tackle the gender pay gap. A similar proportion felt that senior bosses should disclose their own salaries. (Londoners were least prepared to discuss pay, the survey said, while those in the West Midlands were most relaxed about it.)

Now if you believe any of this, you will also believe that hedge fund managers are shy, nervous types who keep their private savings under the mattress. For had this survey asked people whether they were faithful to their partners, or drank a safe number of units per week, they might have got a marginally less fabricated answer. People don't want their salary made public.

Imagine if the UK Treasury did what its Italian equivalent did last week, and published every single citizen's earnings and tax contributions on the internet, without warning. There would be a major scandal. Missing discs would pale into insignificance. The Government would be brought down by a wave of protest, muted only by the number of people online savouring the surreptitious pleasures of finding out exactly what their workmates and neighbours earned. Look no farther than the enthusiasm with which, a few years ago, Britain greeted house price websites, the curtain twitcher's paradise, that allowed them to find out what next door had sold for.

Needless to say there is great inconsistency in our attitudes. We demand transparency from politicians: we know to a penny how much they earn, and want to know what they choose to spend in John Lewis. But we insist, obsessively, illogically, on keeping our secrets.

I am convinced that, in times of economic downturn, a Bear Grylls policy of survival is more effective than gnawing envy when it comes to salaries, both in the workplace and the community. Knowing a colleague's salary is bigger than yours should make you secure, not jealous: he is more likely to be made redundant before you are. And those big cars on the Jones's driveway next door? Think of the £400-odd road tax sting awaiting them, and the weekly cost of a tank of petrol. But even as you pity them, don't expect them to share their grief. It's still a secret.

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