As an artist whose work is so much about the body, it seems natural that Antony Gormley should be interested in dance. For years, he has cast his own body, placing it on top of buildings, in trees and on gallery ceilings, willing us to look at our own bodies, and our selves, in a new light.
An invitation last year to design the set for a dance performance, working with the choreographer Sidi Larbi Cherkaoui and warrior monks from the Shaolin temple in China, seemed singularly apt.
"I've always been interested in dance because it is one of the bravest and most direct art forms there is," Gormley says. "Dancers' bodies have become the instrument through which they communicate their vulnerability, allowing the body to become a direct evocation of thought and feeling, without anything coming in between. It's an extraordinary thing."
Underpinning all this is a long-standing interest in Buddhism and spirituality. During his twenties, Gormley spent two years in India living in monasteries and practising meditation. The central strand of ideas in his work stems from this time: ideas about the conscious body, of stillness in the present moment, and of perception.
The Shaolin monks are a Buddhist order legendary for their training in kung fu. They lead a disciplined life in a mountain monastery in central China, where they train for at least five hours a day until they can move with great agility and speed, within which there is a spiritual dimension.
"I'm very aware that the premise of, I think, all spiritual traditions is that somehow through the disciplining of the body, you free the mind. When you visit the meditation cell of St Francis of Assisi, you will see that it is a stone-cut chamber about 4ft square. Gandhi and Nelson Mandela both spent time in prison, and through that achieved extraordinary powers of communicating a message," Gormley says.
To come up with a set design that would work within the discipline of kung fu, Gormley went to watch the monks train at their monastery in Henan province. "The monks have a wonderful freedom of spirit. They're as interested in hip-hop and contemporary culture as they are in the Buddhist sutras. One of the warrior monks told me that he was there solely to learn kung fu. 'I'm not interested in Buddhist philosophy,' he said. But through the physical discipline he is getting it anyway – no theory, all practice.
"The warrior monks are very hardy and the arrangement at their monastery is very basic, although they don't follow the strict meditation rituals of other monks. You're denied a lot of the basic comforts we would think of as essential," Gormley says.
"The thing that struck me the first time I went to China, in 1995, was how many people there are. In a factory we went to look at, I was astonished at the domestic arrangements for these very young girls. Bunk beds were stacked up five or six high. And when I saw the monastery next door to the Shaolin temple, the dormitory arrangements for the monks were very similar, very tight. These were human lives in storage, filing shelves for bodies."
The set idea Gormley came up with is very simple, relating in a quite obvious way to the living arrangements he saw in China. He designed 21 wooden boxes, like open coffins. Made of spruce, they are three times as high as they are wide and conform roughly to human dimensions. They could be a tomb, a bed, a table, a shelf, a boat or just a box. In Gormley's mind, this simple object becomes something existential.
"They are rather lovely because they are so ordinary, but the colour and texture of them works very well. The box, on one level, is about accepting or recognising our limitations and how we can escape or transcend them. For me, that's the basic premise. Whether people will see that, I don't know. They are very simple things but can be very rich in their potential for being extended and occupied in different ways.
"You can be on them, in them, by them. But you occupy them mentally by how you think of them. Is this a pillar? A sentry box? Is this a table? A bath? And the way the mind runs through 10 or 12 different ways of inhabiting the box and what it is," he says.
There is one extra box, an anomaly. Made of aluminium, it is a dull, dark grey. It was designed for Cherkaoui, the lead performer. It is the star's box, a bit special, though Gormley is not entirely convinced that it works. "Larbi wanted his aluminium box, and it was sweet how much he wanted it. So we made one. Maybe it's not a bad thing to have an exception that proves the rule but I wasn't sure whether it deserved to be there; it rather undermines the others.
"It reads like the box a magician might have, or a cryogenics experiment. If you were going to be deep frozen for the next 5,000 years, you might have a box like this. It's a bit futuristic, a bit space age, a bit techno. He was dead keen for it – and why not?" Gormley says.
Originally, the sculptor thought the boxes would be static structures. He now accepts that he underestimated Cherkaoui's creativity, for his boxes are used in almost every scene, as a kind of extension of the body of the dancer. In one scene the boxes will become a lotus flower, wooden petals blossoming in a way that defies their rigid architecture. They become dominoes, as the boxes, each containing a monk, clatter down across the stage. They will become an instrument of sound as they are dragged around the stage on one corner, like a gramophone needle. And in one dormitory scene, the monks test the context of their lives by hitting the inside of their box, hammering against their limitations.
"One of my favourite scenes is in the dormitory where the monks are all lying horizontal and the boxes are all open towards us. It is like a mass grave. We recognise that the bodies are alive and asleep and they have their own patterns of tossing and turning in their sleep, but then that tossing and turning becomes a curiously co-ordinated and collective act. Where they all turn and begin to walk in their sleep, still lying horizontal, their legs lifting, moving in unison, all 16 of them in their boxes – I think it works extremely well."
In 2005, Gormley worked with the choreographer Akram Khan and Cherkaoui on Zero Degrees, a performance that was well received. It has recently been on stage in New York. Gormley's contribution was a pair of life-size silicone dummies.
Modelled from the bodies of the dancers, one was rigid and standing, the other floppy. They were mostly silent observers on stage, although they were brought into the performance at times. In one scene, Cherkaoui pleads with the dummy, on his knees, begging it to love him; of course, the dummy does not respond, appearing to reject him.
"It has everything to do with how we project volition and motivation on to each other," Gormley says. "When you see that process going on with a dummy, it reveals something about that very process and the whole thing about worship or subjugation."
Gormley thinks deeply about his work and the meaning he hopes to achieve. There is a kind of earnestness in the hope that his work can induce a level of psychological reflexivity that could change lives. But, who knows, he may be right – and if he is not, his intentions are genuine and well meant.
That his work is so accessible and popular with the general public has prompted a sneer from some art critics who think it is not difficult or challenging enough. Or maybe they are merely irritated by his success: his work is everywhere, from the Angel of the North on the A1 to his latest proposal for Trafalgar Square's fourth plinth, where he would like members of the public to stand on the plinth for one hour at a time; another meditative endeavour.
What cannot be denied is that Gormley is intelligent and articulate; not qualities every successful artist is blessed with. He is not cynical, neither is he naive. What I think he wants is for us to see in a different way, to see the world and our place in it in a way that is perhaps less Western and rational. Last year, as part of the Hayward Gallery exhibition Blind Light, he placed human figures on top of buildings near to the gallery and on Waterloo Bridge. Isolated and exposed, they were haunting, fragile and vulnerable. They caused a few problems; the police received phone calls from members of the public concerned about the suicidal man on top of a building.
"It's the alien invasion thing, a disturbance of the normal order," Gormley says. "It invites you to look again, although if that is all it does, then it's not really succeeding as it doesn't achieve a level of reflexivity. The question you then ask is, 'What is this thing doing here?' If that doesn't end up with you asking the same question of yourself, it hasn't really done anything more than be an irritating bit of decoration."
And this is what Gormley wants from his work on stage. His boxes are more than just props; they work within the performance, adding a layer of meaning. And even if they don't work for everyone, they are a testament to the fertility of his mind.
'Sutra' is at Sadler's Wells, London EC1 (0844 412 4300), 27 to 31 May