A thick blanket of aggregate stretches across the turbine hall, but what appear initially to be sunflowers seeds in their plump striped shells are, in fact, porcelain replicas. We are, alas, no longer welcome to walk on them, after Tate decided that ceramic dust created by trudging across the shingle would be harmful to inhale. Just contemplating the expanse from the lofty bridge, however, we may still be uncomfortable to hear that the people of Jingdezhen, a city renowned for its Imperial porcelain, have so conspicuously laboured just so that we might have flopped on the surrogate beach or scuffed across it thinking about lunch.
This discomfort is partly Ai Weiwei's remit. He invites us to ponder issues of exploitative labour flagged by 'Made in China' stickers; although 'Sunflower Seeds' is the antipathy of mass production, as each one of the 100 million or more seeds have been moulded, painted and kiln-fired twice by hand. Video booths ask us to respond to questions posed by the artist, such as: What does this work say about society? The answer mutates according to which society we apply it to. But, while sunflower seeds are here the stuff of pet food and slimmers' snacks, in China they evoke mass coping under Mao. And so Ai's campaign for the freedom of information and expression in China becomes implicit in this blurred rectangle of apparent sameness. Once the circumstances involved are grasped, a grey visual encounter gives way to the awe and politics of very large numbers.