Artes Mundi is an unusual creature. It is a biennial exhibit for Cardiff, but with an emphasis on education projects and gaining as wide an audience as possible in place of the more usual, her­met­ic­ally sealed, art-world shindig. It is, too, a con­tem­por­ary art prize, offering a weighty £40,000 to the winner, that takes an unusual approach to selection. Two curators - this year Portugal’s Isabel Carlos and Bisi Silva, based in Lagos, Nig-eria - go on a global search for artists with solid re­pu­ta­tions on home turf who are beginning to emerge on the in­ter­n­a­tion­al scene, and who make work that, in one way or another, addresses the human condition.

On paper, that last criterion looks awfully vague. But it might be the secret of Artes Mundi’s success, providing enough of a framework to guide the curators while granting them the freedom to make their mark, bringing issues and themes into focus and grouping together artists working towards allied goals.

For this, the third in­carn­a­tion of Artes Mundi, Carlos and Silva have done a good job of sharpen­ing up their broad brief, col­lect­ing artists who take a poetic, often ambiguous, approach to the political.

The show opens with Lida Abdul, an Afghan-born artist who left the country of her birth after the Soviet invasion in 1978 and returned some two decades later intent on examining the place and culture she had left behind. In the film What We Saw upon Awakening, a gang of black-clad young men heave and strain at white ropes attached to a ruined building, per­form­ing an invented ritual that is at once futile and hopeful.

Brick Sellers of Kabul takes another sideways look at re­con­struc­tion, filming a long queue of little boys, lining up to exchange bricks they have salvaged for cash. Filmed in a fugue-like, languid style, with largely silent soun­dtracks, these pieces are at once im­pen­et­r­able - the purpose of these ce­r­e­mon­ies is never clear - and incisive, con­dem­n­ing the de­struc­tion of a nation while codifying the re­si­li­ence of its people.

Abdul’s work seems, in this context, akin to Source, a video piece by the Dundee-based duo Dalziel + Scullion, in which a child moves through a landscape, directly ex­per­i­en­cing his sur­roun­d­ings with all five senses. It is un­den­i­ably political, even polemical, asking us to re­con­sider­ the position of the human in the world - but one that never hectors, simply offering the sensuous and sensual in­spec­tion of an en­vir­on­ment as an al­ter­n­at­ive mode of being.

Susan Norrie takes a more direct look at man and his en­vir­on­ment, doc­u­ment­ing and re­s­pond­ing to the impact of a torrent of molten mud unleashed by an oil drilling outfit in East Java. A bank of monitors screen doc­u­ment­ary footage - of the mud, protest marches and tan­gen­ti­al reactions, including a punk gig - while a more med­it­at­ive piece shows a man climbing a mountain, holding a baby goat that is never sac­ri­ficed.

N S Harsha - who took the Artes Mundi Prize last month - leavens his work with a healthy does of humour. A new series of paintings, Come Give Us a Speech, shows hundreds of figures seated on plastic chairs, listening intently, perhaps for the viewer’s reaction to the work.

All human life is here, with artists, his­t­or­ic­al figures and deities seated alongside anonymous re­p­res­ent­at­ives of every race and creed. It’s a thor­oughly charming piece, and one that cheekily subverts a slightly sugary call for global harmony.

On the floor, Harsha has painted a site-specific work in which headless school­chil­dren are bombarded with re­p­res­ent­a­tions of famous monuments and questions culled from textbooks. It’s a surface to be played on and enjoyed that offers a barbed comment on the way we drag children around museums, whether they like it or not.

Abdoulaye Konate stands out thanks to a more agit-prop approach to his political concerns. His large-scale works in fabric - a material chosen as re­p­res­ent­at­ive of Konate’s native Mali, as well as for practical reasons when he found himself unable to buy paint - are not always subtle. Le Dos a l’Aame sees three shrouded figures em­blazoned with symbols - the Star of David, a cross, the Statue of Liberty - one of whom is carrying a bundle of firewood tied up in the Chinese flag. More effective, and affecting, are such pieces as Homage aux Chaus­seurs du Mande, its surface covered in a dense patchwork of cultural artefacts and talismans, and Gris-gris Blancs, in which Konate has re­in­ven­ted those talismans using a re­stric­ted palette and repeated forms to render them universal.

Rosangela Renno, the first of two Por­tuguese artists on the shortlist, uses found materials of a very different kind, re-present­ing pho­to­graphs or reworking newspaper reports. In Esphelho Diario, the artist takes on the role of 133 other Ros­an­gelas, narrating tales culled from the tabloids ar­bit­rar­ily connected by a name. Elsewhere, Renno takes slide pho­to­graphs of crime scenes and arranges them on light­boxes, robbing them of any sen­sa­tion­al thrill.

While Renno offers cool meta-analysis, Vasco Araujo’s work at times verges on the lurid, matching statuet­tes bought at junk shops with texts on incest by the Marquis de Sade - a dis­tur­b­ing jux­ta­pos­i­tion of suburban tedium with sexual violence. He also works in a quietly lyrical mode, filming a girl playing with bones in an old san­at­or­i­um, or asking vicars to discuss community and in­di­vi­du­al­ity with reference to Benjamin Britten’s opera Peter Grimes.

Last but de­f­in­itely not least comes Mircea Cantor. Born in Romania and now based in France, Cantor uses different media to create arguably the best examples of the subtly political thread that binds the Artes Mundi artists together.

Diamond Corn is a sublime crystal sculpture of a staple crop, mounted on a plain cardboard box. In the film Deer­par­ture, a wolf and a deer pace the floor of an empty gallery in a permanent state of uneasy truce. Add to this silent footage a flag slowly burning on its pole and a triptych of pho­to­graphs of desire lines, the human routes forged in defiance of planners’ straight paths, and Cantor’s work begins to offer a de­lib­er­ately non-specific look at national identity, the in­di­vi­du­al’s re­la­tion­ship to the state and the uneasy ebb and flow of glob­al­ised politics.

Though he did not win the prize, it is hard not to see Cantor’s in­stal­l­a­tion as Artes Mundi’s cen­trepie­ce this year. His unforced, carefully con­sider­ed, reductive approach is as open as the ex­hib­i­tion’s theme and, more than any of his peers here, he makes an oblique approach work, letting the audience explore his al­leg­or­ies without ever stooping to lecture.

This review was first published in The Herald on May 30th, 2008.