The stage we're going through

What exactly is theatre? What's it for? A major festival has set up an inquiry to find out, with the barrister Baroness Kennedy on hand to ensure fair consideration of the question. Paul Taylor reports

When Rose Fenton and Lucy Neal, the artistic directors of Lift (London International Festival of Theatre) first mooted the idea of conducting their Enquiry into the nature of the art form, the response of Dame Helena Kennedy QC, then their chairman, was an emphatic: "No! Nobody believes in inquiries any more; they are so discredited."

When Rose Fenton and Lucy Neal, the artistic directors of Lift (London International Festival of Theatre) first mooted the idea of conducting their Enquiry into the nature of the art form, the response of Dame Helena Kennedy QC, then their chairman, was an emphatic: "No! Nobody believes in inquiries any more; they are so discredited."

It's a fair point. Far too many inquiries have tendentious terms of reference, or head straight to foregone conclusions because of built-in Establishment bias. (Hutton, anyone?) Or they seem, in their manner and procedures, prejudicially remote from the world they purport to analyse.

But Kennedy, that multitasking barrister, was won over on being told what kind of inquiry the artistic directors had in mind. And she captured the spirit of the enterprise precisely when, in her testimony, she described it, as "different: playful, open, exploring possibilities - theatrical".

The Enquiry, part of a lengthy self-questioning process by Lift about its role as a producer of international theatre in London, began in May, took a short break and reopens today. So this is a good moment to examine what it has been up to so far and to look at what it has in store.

"What is theatre to you?" - Lift has invited 100 people to address that direct, non-leading question. Connected in diverse ways to the performing arts, the Enquirers are an intriguingly mixed bunch, ranging from the artistic director of the Royal Shakespeare Company to a 14-year-old pupil at Holland Park School, and from a Buddhist monk who is the caretaker of the London Peace Pagoda to the chair of the British Council. Groups as well as individuals have been recruited.

The liberating twist is that testimony need not be given as a conventional talk. It can be presented as a performance piece, or an installation, or however the testifier sees fit. As Kennedy implies, one way the Enquirers are given to probe the fundamental principles of theatre is by testing them practically. And to ensure that they aren't inhibited by a venue that sets up specific or restrictive expectations, the project is unfolding in the Bargehouse, a welcoming shell of a building on the south bank of the Thames. This provides the tabula rasa necessary for free reflection.

The place has hummed with thoughts about what characteristics are crucial, and peculiar, to theatre. David Lan, the artistic director of the Young Vic, began by turning the question around: "What's theatre for? Let's start somewhere else.

"What is cinema for? We know darkness leads to depression and bright light lifts the spirit. I've begun to wonder if what is at the heart of cinema's power over us is the visceral delight of sitting in a darkened room watching the play of brightly coloured lights on a screen. Perhaps the film itself - its particular narrative, emotions and so on - is secondary."

Having characterised movies as the answer to some primitive psychosomatic craving that can be satisfied just as well individually as in a group, Lan then stressed the indefeasibly communal nature of theatre. "And the theatre? The theatre is a way for strangers to come together in peace."

The role of the audience has often been stressed during the Enquiry, from an aesthetic and a political angle. The fact that theatre's whole existence is in the present tense - that it consists in the exchange of energy between performers and audience at a particular spot and time - has surely never received such extreme expression as it did in the impassioned testimony of the RSC chief, Michael Boyd: "We sometimes call ourselves ice sculptors in the theatre because our work only lives on in people's memories, but even that overstates an independent substantiality to what we make. The reality is that our art form only exists in the space between the audience and the player, in a moment of trust, a collective encounter hanging in the air."

Julian Crouch, the designer of that grotesque masterpiece Shockheaded Peter, came at the same proposition from a different direction in an entertaining session where he created a mask over his own face before our very eyes and offered the striking perception that "the essential act of theatre can never be photographed because it's invisible" - at its best, the completion by the audience of what an imaginative production leaves to the imagination.

There's a strong political potential in this art form where practitioners and public breathe the same air. In the Enquiry, a moving performance of a piece developed in Bethlehem with Palestinian schoolgirls, whose lives keep being reduced to those of caged animals during capriciously intrusive curfews, was a piercing reminder of the precious, fragile freedom of assembly that theatre symbolises, depends on and has at times been denied. Helena Kennedy has published a powerfully argued book, Just Law, about the disturbing erosion of our civil liberties by this government, including "repeated efforts to reduce trial by jury for citizens on a whole range of issues".

Her testimony referred to this Enquiry and to theatre as "a sovereign space where our freedoms can be imagined, rehearsed, defended... Nothing could be more important today than celebrating theatre as an open public place where everyone can enjoy every side of each other's human stories." She also quoted Ron Vawter of the multimedia Wooster Group in New York to the effect that "fun is a very silly word, but a very productive state".

Kennedy's remarks help to highlight the way in which the "sovereign space" of theatre has an intrinsic desire to become either a courtroom (at one end of the spectrum) or an everything-up-for-grabs experimental laboratory. Western drama is, after all, the offspring of Greek democracy and it's no coincidence that the Oresteia, the primal tragic trilogy, culminates in a trial and a vote. Theatre, by its very form, offers a heightened image (often painfully lacking in the real world) of people being held to account in person and in public: hence the double power of the "tribunal theatre" at the Tricycle, with its eloquently edited reconstructions of the Stephen Lawrence inquiry and others.

Alternatively, theatre can present the audience with the blank slate of a bare stage and, on this metaphor for a weirdly recovered aboriginal state, conduct subversive social experiments and test dangerous hypotheses. It's the desert-island scenario that dramatists as different as Shakespeare, Marivaux and JM Barrie have developed. There was a funny and touching variant of this during the Enquiry in the session conducted by Project Phakama, an arts exchange initiated by Lift.

Theatre's salutary capacity to suspend outside differences for the duration and to create an alternative world from scratch was illustrated at the Bargehouse by a participatory session where the multinational audience in an empty room was set the task of constructing a huge map of the globe with sticky tape on the floor and then peopling the map, one by one, while telling a story from the life of another group member.

In a highly intriguing-sounding session that's still to come, the accent will be very much on theatre-as-experiment. On 14 June at the Purcell Room in the South Bank Centre, a piece called Perceptions and Realities: The Science of Theatre will reveal the fruits of a collaboration between the director Katie Mitchell, our most original dramatist, Caryl Churchill, and Mark Lythgoe, a neurophysiologist at the Institute of Child Health, UCL, and a leading light of the sci-art movement.

The overarching question here is: how does the mind relate to the world and how can theatre help to investigate it? Lythgoe explains that one of the sections is "an attempt to create a performance that is so abstract that it forces the audience to let go and take in all the information at face value without any of the 'top-down perceptual processing' that superimposes forms of prior knowledge on what we experience". The point of the experiment is that this is likely to be easier said than done.

Another section, Lythgoe says, will involve actors struggling to represent "ambiguity", combining (say) a "happy voice" and a "disgusted body" in equal proportions. The strength of the audience's likely desire to resolve such ambiguities by creating an illusory explanation (such as "mania") is what is being tested. Theatre enables Lythgoe to embody, dramatise and ponder these profound perceptual puzzles in an interactive exchange with the public.

Patently, this Lift season is in the process of proving on our pulses the truth of Peter Brook's remark that "theatre reopens what definition closes".

The Lift Enquiry continues to 21 June ( www.liftfest.org)