Roman Ondák – review

Some artists court fame. Others shrink from it even as their reputations grow. The Slovakian Roman Ondák is one such figure, an artist whose beguiling and intelligent ideas have reached an international public that may not remember (if it ever even noticed) his name. His is an art that puts other people first on principle.

In Germany, in 2007, Ondák asked museum attendants to mark the height and names of visitors on the gallery walls. Gradually this humble childhood custom gathered into a full-scale public phenomenon as more and more people joined in. The black marks on the white walls accumulated into something like the scattered sparks of a comet blazing through one gallery and into the next. Between them the visitors had made a beautiful sight; the work was called Measuring the Universe.

In 2004 Ondák gave chocolate bars to 500 steel workers in a Japanese factory to use the silver foil as they pleased. The miniature sculptures they made were displayed en masse: a collective portrait of the workers' extraordinarily various forms of creativity as well as their knowledge of metal. In 2007 the children of San Francisco imagined their city a thousand years hence, drawing themselves into the picture, so that one saw multitudinous visions of the future populated by the here-and-now.

There have been shows specially created for people who shun art galleries, and shows by people whose work might ordinarily be shunned by those galleries. There have been shows, like the one where the ticket desk kept appearing in different places, or crowds kept reappearing, that turn the gallery-going experience inside out.

And in Venice, during the last Biennale, Ondák sent up the whole idea of national pavilions and the competition between them, simply by encouraging the Biennale gardens to grow right through his (Czech and Slovak) pavilion. The institution became meaningless, not much more than an open-ended box through which visitors hesitantly progressed, uncertain of beginning or middle or indeed of art itself, of what was inside and what was out. A political idea translated into pure horticulture, it was one of the most beautiful – and popular – pavilions that year.

For Modern Art Oxford, 45-year-old Ondák has created something equally simple but more affecting. The light is low and artificial in the upstairs gallery; the windows are blacked out. The space is fuggy and yellow and contains nothing at all except what appears, at a distance, to be some sort of space rocket. Across the gallery it looks small and slender, a child-sized edition in red, white and blue with a little flag painted near the top and the words "Chile" and "Fénix 2". It is an exact replica – tarnished, battered, scraped, stained and viewed around the world last year – of the capsule used to rescue the 33 Chilean miners.

The claustrophobia one imagined is made real and immediate. The metal tube is so narrow in diameter that it would only take a few extra pounds, you feel, and the body of a grown man might not fit. The metal cage, the single airhole, the emergency bottles of oxygen: all speak of life and death weighed in the balance.

Look up and you see the black shaft above into which this capsule fits as tightly as the chamber into the bicycle pump. A faint spot of luminescent blue suggests the possibility of a sky above. But the idea that one cylinder could possibly fit into the other, transporting a man to freedom, seems dangerously implausible. A couple of millimetres and the whole operation would be stymied.

At which point, the experience in the gallery suddenly seems implausible too. How is it possible that staring at a replica in this safe and neutral place could cause a surge of dread? The simple introduction of reality into unreality is part of it, real-life experience brought into the white-cube gallery. But the people around you are also a part of it.

Ideally, one would see it in a crowd, but even one or two visitors will do. You are all here in the gloom, as the 33 were, closely confined with no means of escape except this tube. Numbers, body counts, the eye of the needle: the imagination is powerfully prompted by the presence of others. Time Capsule puts everyone who sees it on the spot.

There is a crowd – a teeming, roving crowd – in another work here. Three hundred people responded to Ondák's invitation to pile into one of Modern Art Oxford's galleries in almost total darkness. The trace of this event is Stampede, a film with the appearance of night vision, projected continuously on the end wall of the same gallery.

Again, you are as they once were, milling and watching. But you have also become an audience to those previous visitors. At first they appear through the entrance behind you one by one, then in pairs and finally pressing and forging in groups. Even when the gallery is crammed, the citizens united in one body politic, there is a constant movement rippling and building; the proverbial tide of humanity.

All are equally disorientated by the darkness, but everyone behaves differently, hugging the walls, waving, cowering, striding, talking. Some try to dispel the darkness with the screens of their mobile phones. Perhaps the viewer searches for a counterpart in the crowd, or for a hero to follow. And then all of a sudden it's over.

People exit the claustrophobic crush at speed, or at least some of them do. Others linger, watching the spectacle, or even becoming the spectacle in a self-conscious bout of kissing. The sight is absorbing, comical, surprising, rich, and strangely poignant as the gallery drains. In the long tradition of art that involves the public as both viewer and performer, Ondák has proved himself capable of directing (and affecting) multitudes of people with the simplest of ideas. The Turbine Hall surely beckons.