Bryn Terfel may have cancelled his date with Wagner’s Ring Cycle, but you’re still keeping the faith. Those tickets are booked, and the preparatory CDs have been bought. 14 hours of Teutonic myth are looming menacingly on the October horizon.

But even if you’ve already seen Keith Warner’s Royal Opera production in its instalments, you might be forgiven for asking: just what does the whole thing mean?

The good news is that thousands of musicologists, philosophers and general Wagner pundits have had a go at answering that question. The bad news is that, as a result, there are more theories flying about on the ultimate meaning of Wagner’s Ring than there are about who shot JFK.

Never mind. That’s part of the fun. If Warner’s staging hasn’t followed one route, at least it has opened up a tantalising set of references to navigate by. What follows are just a few paths through the labyrinth.

JUST A FAIRYTALE

That argument may have worked for Tolkien when he plundered Wagner to come up with Gandalf, the hobbits and “one ring to rule them all”, but the great man himself had other ideas. And it’s just as well, as 25 years spent simply recycling a set of medieval poems really would have been a waste of time. That’s the reason directors insist on reshaping and reimagining the Ring with every new production, and why every time they do so you find the inevitable chorus of naysayers asking for their beloved operas to be given the proper, naturalistic treatment.

But Wagner used myth and legend for a reason – he thought it was the best way to make us agree with his radical agenda. Just as the Greek tragedians depicted gods and monsters, so Wagner turned to Norse mythology in the service of his radical vision of the world.

Classic example Otto Schenk, Metropolitan Opera, New York, 1986. Quaint, pretty, and entirely vacuous.

Does it fit with the Royal Opera’s staging? Thankfully, no. Keith Warner’s Ring plays out in grim laboratories, bourgeois salons and office towers – not picture perfect mountaintops.

IT’S POLITICAL

It certainly started that way. The composer who began the Ring in 1848, was, after all, a fully paid-up socialist revolutionary. A year later he was exiled from Dresden for subversive activity and had published a poem entitled The Revolution, in which he wrote: “I will destroy every wrong. I will destroy the domination of one man over another. I will shatter the power of the mighty, of the law and of property.”

Broadly speaking, the central plot of the Ring tallies. Its main thrust is, after all, the transfer of power (via the ring itself) from one authority (the Gods, led by Wotan) to another – mankind, of whom the hero Siegfried is the shining example. Wagner believed that too much power was concentrated in the hands of a privileged elite. And, inspired by a new generation of agnostic thinkers, he felt blind religious faith could only hinder the establishment of a more just world order (led, naturally, by artists such as him).

Classic example Patrice Chéreau, Bayreuth Festival, 1976. The Ringmet the Industrial Revolution, with stunning results.

Does it fit with the Royal Opera’s staging? Undoubtedly. Here the gods sit around in smoking jackets as their sweaty engineers (the giants, Fafner and Fasolt) build Valhalla for them.

IT’S PHILOSOPHICAL

Well, yes – but whose philosophy? By the time Wagner completed the Ring in the 1870s he had forgotten his wild-child socialism and turned to a much more abstruse master: Schopenhauer, a grim German who cheerily wrote about how all of life’s pursuits were ultimately pointless, because they couldn’t connect us to the ineffable mysteries of the unconscious. So much for getting the ring out of the hands of despots and into the hands of the idealists: direct action of that sort is ultimately futile.

That’s why the cycle seems to turn inwards as it reaches its conclusion, and why you’re quite likely to be mystified the first time you hear Siegfried’s love duet with Brünnhilde – a conversation dominated by talk of “laughing death” and “enlightening love” rather than, say, one of them suggesting they go for a romantic supper. In Schopenhauer-speak, only a metaphysical love can bring any lasting satisfaction.

Arguably it’s this bleak sort of hope that drives the Ring on to its (literally) incendiary climax. In Götterdämmerung, having snatched the ring from Siegfried’s corpse, Brünnhilde hails the destructive power of fire – and her imminent suicide – as the only release from all the scheming that Wotan and the gods should never have embarked on in the first place.

Classic example David Alden, Munich, 2003. Giant rats invade the stage at the climax. Doesn’t get much more pessimistic than that.

Does it fit with the Royal Opera’s staging? The final note of Warner’s Götterdämmerung is optimistic – a child, borne aloft from the crowd – but both this final opera and Siegfried are saturated in appropriately abstract gloom.

FREUDIAN SLIPS

You don’t have to be a psychiatrist to know that most of the characters of the Ring have serious issues. But what’s astonishing is how perceptively Wagner reacts to them. Siegfried, the hero who supposedly knows no fear, is gripped by a primeval panic when he meets his first woman (Brünnhilde) and nervously wonders if she might be his mother. Wotan’s existential plight – he can only get the ring by breaking the very rules he set the world to live by – is a fascinating portrait of a split personality.

Others have gone even further down the psychoanalytical route. What is Siegfried’s quest to forge his broken “sword” all about if not the angst of puberty? From a Jungian analysis – yes, this has been done – Wotan’s plight is classic ego versus anima, and his daughters (the warrior Valkyries) are just a manifestation of his unconscious. Seen like this, the entire story could even be seen as taking place inside Wotan’s head.

Classic example Wieland Wagner, Bayreuth, 1951. Abstract settings, deeply symbolic scenery. Some say it’s never been bettered.

Does it fit with the Royal Opera’s staging? At times, very much so: Wotan gives Brünnhilde a full-on snog before sending her to mortal sleep – a disturbingly plausible look into his particular psyche.

IT’S ECO-FRIENDLY

Could the Ringbe the first environmentally friendly opera? It starts, after all, with an act of pollution – the theft of the magic Rhinegold from the watery Rhinemaidens. Wagner idolised nature, and the Ring can be seen as a grim parable of environmental catastrophe.

All the goodies in the operas – Brünnhilde, Siegfried, Siegmund – tend to revel in the beauty of the natural world. All the baddies – Wotan, Alberich, Hagen – do things to disrupt it. Wotan’s very authority derives from an act of desecration, when he broke his spear out of the world-ash tree that holds the earth together. And what happens at the end – Brünnhilde releasing the ring into the waters of the Rhine – could be seen as atonement.

Classic example Stephen Wadsworth, Seattle, 2001. A vision in green – and there was even a real horse.

Does it fit with the Royal Opera’s staging? Warner’s Rheingold begins with naked blue Rhinemaidens, but by the time we get to Götterdämmerung, the Rhine has wind turbines and factories lining its shores.

ALL HAIL THE ARYANS

Not a popular theory for die-hard Wagnerites, but you don’t have to be a raging conspiracy theorist to notice that it’s the blondes in the Ring who get the best tunes. Hell, there’s even a “master race”: the Volsungs, spawned by Wotan himself to further his plans for world domination by proxy. Their resulting progeny is the musclebound, blue-eyed Siegfried, whom Wagner once called “the man of the future”.

Still, it’s a long stretch from there to argue that Wagner would have applauded the Nazis’ acts of genocide. Plenty of scholars have tried it: they say Wagner gives the dwarfs “Jewish-sounding” music, and stereotypes them as money-grabbing fools. Then again, that’s pretty much the universal cliché for dwarfs.

Classic example It would be a brave director who tackled antiSemitism head-on without being misunderstood. We are still waiting.

Does it fit with the Royal Opera’s staging? Warner’s conniving dwarfs are more like diligent scientists than dwarfs; the “Jewish” question is thankfully irrelevant.

A FEMINIST MANIFESTO

Trust the Germaine Greer generation to have a go redeeming all the swaggering machismo of Siegfried and his giant sword. But the truth is they have a point: for every bumbling man in the Ring, there’s a woman with a much better argument. Wotan is permanently in thrall to the mysterious Earth Mother, Erda. His wife Fricka does a magnficent job of exposing what a shortsighted buffoon he is. And, most importantly, at the close of the entire thing, it’s a woman who survives long enough to realise that by sacrificing herself she can save the world. What better endorsement of feminine intuition is there?

Classic example Phyllida Lloyd, English National Opera, 2005. Brünnhilde learns her lesson after turning from bullied wife to suicide-bombing superhero.

Does it fit with the Royal Opera’s staging? There’s a lot in the pot, but girl power doesn’t seem to be one of the ingredients. Yet.

The Ring Cycle, Royal Opera House, London WC2 (www.roh.org.uk/ring 020-7304 4000), from Oct 2

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