As a new book on Latin has become a surprise Christmas bestseller. It's author shares with us 'Ut amator latinus sis', which means, if you'll forgive the pun, 'How to become a Latin lover':

Being savaged by Monty Don is not too bad, really - a bit like being smothered in the furry arms of a tousle-haired teddy bear. All the same, when the TV gardener attacked me a few days ago for perpetuating a class war by promoting Latin, I thought it was a bit much.

I was on Radio 4 discussing my book about Latin, in which I attempt to explain my love for the language - a book which, to my great surprise, has become a Christmas best-seller.

Monty Don's point was that Latin has been used for centuries as a sneaky way of making the middle classes feel more elite; and of putting down the working classes who couldn't get a decent education.

He's certainly right that some people use Latin to show off: barristers with their actus reus (guilty act); gardeners with their digitalis purpureas (fox gloves). And one should be suspicious of those who call more than one genius genii or refer to the auditoria in the local cinema.

But anyone can be annoying with their knowlby Harry Mount edge, using it for squashing people instead of informing them. That's not the same, though, as saying that Latin was intentionally used to exclude the poor from a proper education, as Monty Don suggested.

Until successive Conservative and Labour governments did their best over the past 40 years to dismantle grammar school education, Latin stood alongside other arts subjects - English, French, History, take your pick - as perfectly normal for bright pupils of any class to learn.

It's only since class war was declared on grammar schools, and since Latin has, as a result, retreated to public schools and a dwindling handful of grammar schools, that the language has become the elite subject attacked by Monty Don - who was himself lucky to benefit from a classical education at £24,000-a-year Malvern College and Cambridge.

In 1960, 60,000 children did Latin O-level. Now, just 10,000 do the more basic replacement, the GCSE. And, of these, in 2004, only 3,468 came from state schools.

That slump is the biggest for 500 years. Until the 1900s, classics had been the staple diet of basic British education for half a millennium.

But just because our philistine government has taken away the opportunity to learn challenging, improving subjects at state-run schools, it doesn't mean that people shouldn't go looking for that improvement themselves.

That's why my new book on Latin has been doing so well, selling over 1,000 copies a week. It fills a small hole in the yawning gap hollowed out in the British education system.

Fifty years ago, my book wouldn't have found a publisher. The basic Latin introduction it provides would have been taught as a matter of course in any grammar school in Britain.

No longer. As last week's Ofsted report showed, more than half of England's schools are failing to provide children with a good standard of education. A third of a million children leave school every year without a basic understanding of maths and English.

This is why there is a boom in self-help books such as mine, and Eats, Shoots And Leaves, Lynne Truss's surprise hit of Christmas 2004, which instructs you about grammar and punctuation and has now sold three million copies. The success of authors like us depends on education's failure.

My book is supposed to appeal to anybody who's interested in Latin - whether they have done a lot of it, a little or none at all.

I've lost count of the number of people who have told me they're buying it for their children because those children aren't getting the education their parents took for granted a generation ago.

I was lucky enough to start learning Latin at the age of nine. Yes, there were a lot of rules and words to learn, but the point about Latin is that they are simple rules and familiar words for a nine-year-old to understand.

The nine-year-old brain is particularly good at absorbing information. Once you know Latin, you remember it for good. It's always there, as a framework to underpin your understanding of English.

As a child, I remember particularly enjoying learning how English words derived from Latin ones.

I loved discovering that dominoes are derived from dominus, meaning 'master'. The hoods worn in 1710 by Italian priests were called dominoes. Black, with holes cut into them for the eyes, their name got passed on to the black rectangular playing blocks with their white dots.

How exciting it was to discover that the word 'candidate' came from candidus, meaning 'white'. The term emerged because Roman candidates for election wore togas covered in white chalk to make them stand out.

And what a pleasure it was when you discovered a word with two Latin ancestors, like ' regicide', from rex or regis, meaning 'king' or 'of the king', and caedo meaning 'I kill'.

The fact is that Latin is the most influential language in the history of civilisation - it's something which shouldn't be restricted to an elite. Know a little Latin and you open up 500 years of English literature (as well as a thousand years of Latin prose and poetry).

Latin not only helps you with simple things like the storylines of English literature, so heavily based on classical stories. It also helps you to understand the classically-schooled minds of those who wrote great English literature - for half a millennium up until the 19th century, Latin was the mark of the educated man.

Knowing Latin is like sticking on a pair of X-ray specs. Suddenly you expose the Roman layer that lies beneath the skin of modern Britain; and not just modern, elite Britain, as Monty Don would have it.

With Latin and its history behind you, you end up seeing more everywhere - not only in English literature, but in the way our buildings are built, the way we talk.

The most obvious legacy the Romans left us after their two invasions (Julius Caesar in 55BC, then Claudius in 43AD) was our language. If you understand Latin you'll never leave a sentence dangling in thin air, without the right verbs, nouns and adjectives in their proper place.

You'll also know how those words have changed since the Romans used them. And, if you know exactly how they've changed, you'll know how to use them better.

The father and son writers Kingsley and Martin Amis once had a good row about the word 'dilapidated'. Kingsley said you should use the word however you wanted. His son insisted on sticking to its exact sense: from lapis, meaning 'stone', dilapidatus means 'having stones removed'.

According to Martin, you should really only use it strictly - in the sense that a part has been taken away from the whole.

So Martin Amis acknowledged that you could say that the Parthenon was dilapidated, because the ancient Greek temple had lost lots of its stones in the last 2,500 years. But he wouldn't call, say, the Royle family's sitting room dilapidated because, although run down, it remains structurally sound.

It's a silly row that demonstrates a serious truth. You drive better if you know how a car works; you handle language better if you know how it's built.

And no one would say that knowing how to handle the English language is a thing that should be restricted to an elite, would they?