50th Venice Biennale

'An image', wrote Jean Genet, 'is the only message from the past that has managed to get itself projected into the present.' In Venice the air was hot, the moon was full and moments collided in an atmosphere of uneasy delirium. The present, quite sensibly, refused to hang around - one sweaty blink and it was gone, overwhelmed by a history that refuses to give up the ghost, and a future - if what we witnessed in the Biennale could be so described - as demanding as a demented aunt. Wandering around the Arsenale, a cartoon came back to me - one exhausted person saying to another that the problem with life is that the big questions are always multiple choice.

It is breathtakingly appropriate that Venice was built on land that appears to float; this is a city that revels in deception. Placing art in such a twilight zone is to set up a near-impossible dynamic; what kind of image or idea could possibly compete with such weary magnificence? The temporal slipperiness of Venice is confusing at the best of times, and during the Biennale it's a confusion exacerbated by the sheer volume of things that demand to be looked at. But then if art is a reflection of life, perhaps such chaos is simply a reminder that life is the untidiest thing that ever happens to anyone. ('I need a mess of help to stand alone', sang the Beach Boys.)

Every time you look at art it creates its own conditions. During the opening of this Biennale these conditions could be boiled down (literally) to heat, and too much to absorb in a short amount of time. Yet still, many artworks, ideas and shows managed to make themselves felt - pictures by Mamma Andersson, Chris Ofili, Carol Rama and the painting show in the Museo Correr; Cady Noland, Richard Prince, Fischli & Weiss; Gabriel Orozco; the Scottish, Dutch and Danish Pavilions; Enrico David, Bojan Sarcevic, Magnus von Plessen and others in the 'Clandestine' section in the Arsenale - yet I'm sure I missed some gems. The nature of the exhibition makes it too easy to overlook quiet, very subtle or complex work. Most people who don't live in Venice will take only a few days to visit the Biennale - what we glimpsed this year would take weeks to do justice to.

And of course, now that a month or so has passed and the temperature has dropped, my memory has begun the game it loves so well: the elimination of detail. 'The termites of reduction', wrote Milan Kundera, 'have always gnawed away at life; even the greatest love ends up as a skeleton of feeble memories.' So I will concentrate on one piece that, given the conditions, struck me as the perfect fusion of form and content - a beam of light.

Given the viewing conditions, one piece struck me as the perfect fusion of form and content: a beam of light.

Like a cool hand on Venice's sweaty forehead, Cerith Wyn Evans projected a staccato seven-mile ray of light into the night sky. That his piece was part of the newly created Welsh Pavilion on the Giudecca, away from the chaos of the Giardini and Arsenale, helped; a breezy boat ride transported you to it, and even if you didn't manage to visit the site of origin you could see it every night, wherever you were. Despite its visual simplicity, Cleave 03 (Transmission, Vision of the Sleeping Poet) (2003), is, characterisitically, a complicated piece. In 1703 a cleric and author, Ellis Wynne, wrote his great classic of Welsh literature Gweledigaethau y Bardd Cwsc (Visions of the Sleeping Bard), which was an adaptation of a translation of a Spanish book, Sueños y Discursos (Dreams and Discourses), by Francisco de Quevedo, from 1627. A few hundred years later Wyn Evans had an excerpt of the piece translated into Morse code, which he then projected into the hot Venetian sky.

We first visited it during the day, when the beam was invisible and the sturdy World War II military searchlight vehicle responsible for it, complete with British number plate, sat stolidly in a dry garden, clicking away like an old man with loose dentures. We lay exhausted on the hot grass and looked up at the sky, oddly soothed by the sounds of Morse code being transformed into light. Above us, drifting swallows seemed to respond to the rhythms - in moments of silence they would disappear, only to return when the Morse began. That night Cleave 03 lit up the lagoon and Dan Fox commented that the full moon, which seemed to swing towards the beam as if suspended from stars, looked like the disco ball in Cerith's earlier work.

Cleave 03 is a work of art that synthesizes the idea of dislocation and travel - of language, of time, of place, of people moving, or wanting to move - with a logic built on solid foundations of poetry. Wyn Evans has observed that the piece 'speaks about the importance of positioning oneself in order to see beyond the boundaries of the geographical place you are in'. If there is a better rationale for the Venice Biennale, I have yet to hear it. The opening lines of Visions of the Sleeping Bard are apt here: 'On the fine evening of a warm and mellow summer I betook me up one of the mountains of Wales, spy-glass in hand, to enable my feeble sight to see the distant near, and to make the little to loom large. Through ... the calm, shimmering heat, I beheld far, far away over the Irish Sea many a fair scene.'