'And I believe Aristotle is correct. After all, what are the scenes in poetry graven on our memories, the ones that we love the most? Precisely these. The murder of Agamemnon and the wrath of Achilles. Dido on the funeral pyre. The daggers of the traitors and Caesar's blood – remember how Suetonius describes his body being borne away on the litter, with one arm hanging down?'

'Death is the mother of beauty,' said Henry.

'And what is beauty?'

'Terror,' 'Well said,' said Julian. 'Beauty is rarely soft or consolatory.

Quite the contrary. Genuine beauty is always quite alarming.'

I looked at Camilla, her face bright in the sun, and thought of that line from the Iliad I love so much, about Pallas Athene and the terrible eyes shining.

'And if beauty is terror,' said Julian, 'then what is desire? We think we have many desires, but in fact we have only one. What is it?'

'To live,' said Camilla.

'To live forever,' said Bunny, chin cupped in palm.

The teakettle began to whistle.

Once the cups were set out, and Henry had poured the tea, somber as a mandarin, we began to talk about the madnesses induced by the gods: poetic, prophetic, and, finally, Dionysian.

'Which is by far the most mysterious,' said Julian. 'We have been accustomed to thinking of religious ecstasy as a thing found only in primitive societies, though it frequently occurs in the most cultivated peoples. The Greeks, you know, really weren't very different from us. They were a very formal people, extraordinarily civilized, rather repressed. And yet they were frequently swept away en masse by the wildest enthusiasms – dancing, frenzies, slaughter, visions – which for us, I suppose, would seem clinical madness, irreversible. Yet the Greeks – some of them, anyway – could go in and out of it as they pleased. We cannot dismiss these accounts entirely as myth. They are quite well documented, though ancient commentators were as mystified by them as we are. Some say they were the results of prayer and fasting, others that they were brought about by drink. Certainly the group nature of the hysteria had something to do with it as well. Even so, it is hard to account for the extremism of the phenomenon. The revelers were apparently hurled back into a non-rational, pre-intellectual state, where the personality was replaced by something completely different – and by "different" I mean something to all appearances not mortal.Inhuman,'

I thought of the Bacchae, a play whose violence and savagery made me uneasy, as did the sadism of its bloodthirsty god.

Compared to the other tragedies, which were dominated by I recognizable principles of justice no matter how harsh, it was a triumph of barbarism over reason: dark, chaotic, inexplicable.

'We don't like to admit it,' said Julian, 'but the idea of losing control is one that fascinates controlled people such as ourselves more than almost anything. All truly civilized people – the ancients no less than us – have civilized themselves through the willful repression of the old, animal self. Are we, in this room, really very different from the Greeks or the Romans? Obsessed with duty, piety, loyalty, sacrifice? All those things which are to modern tastes so chilling?'

I looked around the table at the six faces. To modern tastes they were somewhat chilling. I imagine any other teacher would've been on the phone to Psychological Counseling in about five minutes had he heard what Henry said about arming the Greek class and marching into Hampden town.

'And it's a temptation for any intelligent person, and especially for perfectionists such as the ancients and ourselves, to try to murder the primitive, emotive, appetitive self. But that is a mistake.'

'Why?' said Francis, leaning slightly forward.

Julian arched an eyebrow; his long, wise nose gave his profile a forward tilt, like an Etruscan in a bas-relief. 'Because it is dangerous to ignore the existence of the irrational. The more cultivated a person is, the more intelligent, the more repressed, then the more he needs some method of channeling the primitive impulses he's worked so hard to subdue. Otherwise those powerful old forces will mass and strengthen until they are violent enough to break free, more violent for the delay, often strong enough to sweep the will away entirely. For a warning of what happens in the absence of such a pressure valve, we have the example of the Romans. The emperors. Think, for example, of Tiberius, the ugly stepson, trying to live up to the command of his stepfather Augustus. Think of the tremendous, impossible strain he must have undergone, following in the footsteps of a savior, a god. The people hated him. No matter how hard he tried he was never good enough, could never be rid of the hateful self, and finally the floodgates broke. He was swept away on his perversions and he died, old and mad, lost in the pleasure gardens of Capri: not even happy there, as one might hope, but miserable.

Before he died he wrote a letter home to the Senate. "May all the Gods and Goddesses visit me with more utter destruction than I feel I am daily suffering." Think of those who came after him. Caligula. Nero.'

He paused. 'The Roman genius, and perhaps the Roman flaw,' he said, 'was an obsession with order. One sees it in their architecture, their literature, their laws – this fierce denial of darkness, unreason, chaos.' He laughed. 'Easy to see why the Romans, usually so tolerant of foreign religions, persecuted the Christians mercilessly – how absurd to think a common criminal had risen from the dead, how appalling that his followers celebrated him by drinking his blood. The illogic of it frightened them and they did everything they could to crush it. In fact, I think the reason they took such drastic steps was because they were not only frightened but also terribly attracted to it. Pragma tists are often strangely superstitious. For all their logic, who lived in more abject terror of the supernatural than the Romans?

'The Greeks were different. They had a passion for order and symmetry, much like the Romans, but they knew how foolish it was to deny the unseen world, the old gods. Emotion, darkness, barbarism.' He looked at the ceiling for a moment, his face almost troubled. 'Do you remember what we were speaking of earlier, of how bloody, terrible things are sometimes the most beautiful?' he said. 'It's a very Greek idea, and a very profound one. Beauty is terror. Whatever we call beautiful, we quiver before it. And what could be more terrifying and beautiful, to souls like the Greeks or our own, than to lose control completely? To throw off the chains of being for an instant, to shatter the accident of our mortal selves? Euripides speaks of the Maenads: head thrown I back, throat to the stars, "more like deer than human being." To be absolutely free! One is quite capable, of course, of working out these destructive passions in more vulgar and less efficient ways. But how glorious to release them in a single burst! To sing, to scream, to dance barefoot in the woods in the dead of night, with no more awareness of mortality than an animal! These are powerful mysteries. The bellowing of bulls. Springs of honey bubbling from the ground. If we are strong enough in our souls we can rip away the veil and look that naked, terrible beauty right in the face; let God consume us, devour us, unstring our bones. Then spit us out reborn.'

We were all leaning forward, motionless. My mouth had fallen open; I was aware of every breath I took.

'And that, to me, is the terrible seduction of Dionysiac ritual.

Hard for us to imagine. That fire of pure being.'

After class, I wandered downstairs in a dream, my head spinning, but acutely, achingly conscious that I was alive and young on a beautiful day; the sky a deep deep painful blue, wind scattering the red and yellow leaves in a whirlwind of confetti.