Imagine an evening at the theatre listening to words like this. "Thine arms were gyved! Nay, no gyve, no touch, was laid on me. 'Twas there I mocked him, in his gyves..." It's hardly a thrilling prospect. But if the study of Greek and Latin in this country had been quietly stopped after the first world war (as nearly happened), this is how we would now all be experiencing Greek tragedy, for that was a quote from Gilbert Murray's translation of Euripides's Bacchae, published in 1904. It's the leader of the chorus talking to the god Dionysus, who's just escaped from prison - a "gyve" is apparently an old-fashioned word for a chain. In a Greek-less world, that would be about as close to Euripides as we could get.

There are many good reasons for fostering the study of classical languages. Will Hutton recently wrote powerfully in the Observer about how important Roman history is to our own political culture. And what would be lost if we lost our direct links to ancient literature in the original tongue?

Over the past few decades, classical drama has been one of the jewels in the crown of British theatre, from Diana Rigg's wonderful Medea to Tony Harrison's Oresteia. This has been possible precisely because we still have that link to the original words. Tony Harrison knows Greek. Even Diana Rigg would have failed to move an audience with Gilbert Murray's translation.

Murray was not a dud. In the early 20th century his translations seemed up to the minute, and they were politically influential. His translation of Euripides's Trojan Women (a devastating exposure of the after-effects of armed conflict) was performed in Chicago in 1915 as part of the campaign to keep the United States out of the war. If it now seems hopelessly archaic, that's because every generation rediscovers and retranslates the classics for themselves, re-engaging with the original texts.

If we do decide to keep the classics, there's still the issue of who should learn the languages, and how. For centuries Greek has been an exotic minority option. This debate centres on Latin and on the question of whether it is too difficult. In particular, should its GCSE be made easier so that more children, across the ability range can enjoy it?

This is to miss the point. Learning Latin properly is very hard. That is part of the pleasure and the challenge, and it does no one a good turn to pretend otherwise. It's not that the Romans were cleverer than us, but the writing they left behind (which is why, after all, most of us want to study them) is difficult, complex and highly literary. Reading the Roman historian Tacitus is probably best compared to getting to grips with Joyce's Finnegans Wake.

We should not be confusing social exclusivity with an intellectually elitist subject. All bright children, no matter how wealthy or privileged they are, should have the opportunity to learn classical languages. One of the biggest crimes of the national curriculum is having eased Latin out of the maintained sector (though not entirely, I'm pleased to report). But it is no more sensible to put Latin on the curriculum of the less academically able than it is to put Mandarin Chinese or quantum physics there.

In fact, paradoxically, it is the sheer difficulty of Latin that makes it something of a social leveller, and a route to intellectual upward mobility. Questioning my colleagues who teach classics at Cambridge (a university in which roughly 40% of undergraduates across the board still come from the private sector), I found that only about 20% had attended independent schools.

The good news is that, whatever its posh image, Latin is a hard subject in which the academically able thrive. It's rather like maths: money alone can't make you good at it.