A male member of the landed gentry is a gentleman; which, in England, is an interesting thing to be. An old schoolmaster of mine used to maintain that there were only two English words for which no other language had any exact equivalent, and that both were significant indicators of the national character. One was "cant", the other was "gentleman". Whether it was cant or dislike of it which he considered peculiarly English, I cannot now remember: but there may well be some truth in the suggestion that the English use of the word "gentleman" is unique.

Its implications are subtle and complex. The criteria are not wholly those of birth nor do they refer wholly to standards of behaviour, but are a blend of the two. A gentleman may behave in an "ungentlemanly" fashion, but remains a gentleman. Conversely, someone who is not a gentleman may behave "like a perfect gentleman" - without becoming one. "Nature's gentleman" is, by definition, not a gentleman. Yet to say "The fellow's ancestors may have arrived with William the Conqueror, but, dammit, he's no gentleman" is a perfectly comprehensible indictment. The Devil, on the other hand, is well known to be a gentleman. Announcements on college notice boards in Oxford and Cambridge say "Gentlemen are requested.", whereas in provincial universities they say "Students will." Nobody really believes that all the undergraduates at Oxford and Cambridge are gentlemen, or that all the undergraduates in provincial universities are students: but the difference in phraseology indicates a very substantial and practical difference in attitude.

"It is," wrote Cardinal Newman, "almost a definition of a gentleman to say that he is one who never inflicts pain. This description is both refined and, as far as it goes, accurate . . . His benefits may be considered as parallel to what are called comforts or conveniences in arrangements of a personal nature: like an easy chair or a good fire, which do their part in dispelling cold and fatigue, though nature provides both means of rest and animal heat without them. The true gentleman in like manner carefully avoids whatever may cause a jar or a jolt in the minds of those with whom he is cast. He makes light of favours when he does them, and seems to be receiving when he is conferring. He has too much good sense to be affronted at insults, he is too well employed to remember injuries, and too indolent to bear malice. If he engages in controversy of any kind, his disciplined intellect preserves him from the blundering discourtesy of better, though less educated, minds; who, like blunt weapons, tear and hack instead of cutting clean, who mistake the point in argument, waste their strength on trifles, misconceive their adversary, and leave the question more involved than they find it."

And so on. The entire passage is a marvellous piece of prose, a beautifully idealised portrait; but, as Newman said, it is a description rather than a definition, and accurate only "as far as it goes".

A more cynical writer said that gentility is nothing else but old money. Again, this is true "as far as it goes". The effect of old money is indeed powerful and should not be under-rated. (The operative word is "old", not "money". Gentlemen nowadays are more apt to boast of their poverty than of their riches.) "Good breeding", so-called, is not the same thing as old money, but they tend to go together. Backed by old money, advantageous marriages can more readily be made. Talent, as well as wealth, may he inherited. To deny the importance of heredity in human breeding, while recognising and utilising it in the breeding of every other species, seems one of the more perverse hypocrisies.

Nor is this simply a matter of biology. An inherited social position transmits obvious environmental, as well as the more controversial genetic, attributes. Habits, assumptions, disciplines, knowledge, principles, are absorbed osmotically during the process of growing up: and a nexus of valuable relationships-through family, school, university, regiment, club - is automatically acquired. This easy acquisition may be, as egalitarians would claim, unfair, but it is an effective way of equipping otherwise ordinary people to fill a special role in society.

They are secure in their own identity and confident of their social position. They know what is expected of them and are psychologically free to get on with the job. When the system is working properly, the result should be a degree of stability and continuity hardly to be obtained in any other way. An old landed family, belonging to its land as much as the land belongs to it, will build and plant trees for the future. People need roots, a sense of inheriting from the past and bequeathing to the future. To destroy this continuity, to prevent families from handing on what they have inherited or built, is to remove a linchpin, not just from those families, but from the whole community.

There is something else, even more unfashionable, which gentlemen may inherit - a sense of duty. In its basic and most traditional form this duty is military. As the protagonist of Christopher Hollis's novel, Death of a Gentleman, put it, "Gentlemen are there to be shot at, when the shooting's on. That is what they are for, and, whatever the other duties in which the gentlemen of England have failed throughout their history, at least they have never failed in this." If proof were needed, the records of the Public Schools Club would provide it. By November 1914 no fewer than 80 per cent of the club's members were on active service (though there was, of course, no conscription at that time), and by the end of the war 800 had been killed in action.

English gentlemen have traditionally accepted peacetime duties as well. They have supplied generation after generation of magistrates and government servants whose quality, by general consent, is unequalled in the world. On their unstinting voluntary labour, and on that of their wives and daughters, almost every committee and community service in the country largely depends.

More unfashionable still is the concept of "honour", which has always been closely associated with gentility. Gentlemen have the normal share of original sin: they are not by nature more honourable than anyone else. But, at least in times past, their position in society did impose on them a sense of honour and its obligations. "The word of a gentleman" was no empty phrase. Schools for the sons of gentlemen - or, as Chesterton put it, schools for making gentlemen of sons - strove not unsuccessfully to impart a code of honour which would last throughout life. A society which took Newbolt's Vitai Lampada and Clifton Chapel seriously was perhaps healthier and more admirable than our own, which finds them risible.

If vestiges of this tradition survive - and they do - the best place to look for them is in families where the tradition has been accepted unquestioningly for several generations.

Every community needs people of this kind; people who take responsibility, sit on committees, resist pressure, set a tone, and who, in return for these services, receive a certain amount of privilege and respect. Every community does, in fact, produce them. But there is much to be said for deriving the bulk of this class from those who were born and educated to the job rather than from those who come to it through the acquisition of money or political office, both of which conduce to a fund of arrogance ("insolence" in the strict Latin sense of the word) which was rarely found among the old squirearchy.

In its readiness and capacity to undertake these unpaid and largely unhonoured public functions, the English gentry is, again, perhaps unique. There is no precise foreign equivalent. The English gentry has never formed an exclusive caste, like minor European nobles. It merges imperceptibly with social classes above and below. It is hospitable to new recruits, provided those recruits adopt the appropriate pattern of life. At the same time, England's landed gentry includes many families which are much more genuinely aristocratic than the Peers of the Realm who take formal precedence over them. Politicians, industrialists and other dubious persons can be instantly ennobled at a stroke of the Prime Minister's pen: but nobody can make instant gentlemen. The phrase "a good family" in England usually does not mean a titled family.

The system of primogeniture, however, means that many families without title are closely connected to the older peerage. Gentlemen who would be Counts in Europe are Mr. in England. Such a continuous spectrum, with no hard edges, no precise definitions, makes for a closely knit society. The class structure in England is firm but permeable, a combination which renders it more kindly and more durable than its equivalent in most other countries.

Speaking in the House of Commons, at the end of 1971, about proposals to increase the income of the Royal Household, Mr. Richard Crossman, while professing to be a "rational monarchist", said that one of the things which worried him about the Monarchy was its connection with "a certain class and overwhelmingly with the landed gentry". The great danger, he argued, was that the Monarchy would be separated and encapsuled in the class which surrounded it.

But the real danger to the Monarchy, surely, is almost the exact opposite. Mr. Crossman is right in thinking that a Monarchy which becomes too separate from the rest of the community, too strange, too alien, will be dangerously vulnerable: but nothing would more effectively create this situation than the levelling policies which Mr. Crossman and his Party advocate. If they succeed in destroying the social system to which the Monarchy naturally belongs, the hereditary structure of which it is the proper apex, then the Monarch, entirely isolated, standing up like a single tower on a plain, must appear an increasingly bizarre and incomprehensible figure - and will, sooner or later, be discarded.

The English upper classes, as Evelyn Waugh observed in his prefatory note to a new edition of Brideshead Revisited, have survived rather better than seemed probable immediately after the war. But they have been, and are, under continuous attack, directly by a tax system designed to destroy them and their way of life, and indirectly by political and cultural tides which sap their identity and erode their function.

I believe this attack should be resisted, not just for their sake, not merely as an exercise in conservationism, but for the health of the nation as a whole. What is at stake goes far beyond politics. It has become steadily more apparent that a great deal of what used to be considered the English character was really characteristic of the English gentleman, from whom it spread throughout other sections of the community. These characteristics were not - are not - pure gold. They include large faults as well as large virtues. But the traditional English gentleman is not a stereotype of which England need be ashamed. On the contrary, be epitomises much which the rest of the world would be better for emulating.

He was engagingly represented, more than 100 years ago, by Squire Brown in Tom Brown's Schooldays. A Berkshire landowner and Justice of the Peace, his lineage old but untitled, Squire Brown "stopped at home, and dealt out justice and merry in a rough way, and begat sons and daughters, and hunted the fox, and grumbled at the badness of the roads and the times."

When Tom was going off to school, Squire Brown pondered what advice to give him.

"I won't tell him to read his Bible, and love and serve God; if he won't do that for his mother's sake and teaching, he won't for mine. Shall I go into the sort of temptations he'll meet with? No, I can't do that. Never do for an old fellow to go into such things with a boy. He won't understand me. Do him more harm than good, ten to one. Shall I tell him to mind his work, and say he's sent to school to make himself a good scholar? Well, but he isn't sent to school for that - at any rate, not for that mainly. I don't care a straw for Greek particles, or the digamma; no more does his mother. If he'll only turn out a brave, helpful, truth-telling Englishman, and a gentleman, and a Christian, that's all I want."

Risible? Naive? Out-of-date? Perhaps. But there wouldn't be much wrong with any individual, or any class, or any nation, which really lived up to the principles which Squire Brown, speaking for the old landed gentry of England, thought a boy should learn.