Ai Weiwei review – momentous and moving

If there were any who doubted Ai Weiwei’s work matched his reputation, this rollercoaster of a show – racing between his time in jail, the Sichuan earthquake and 3,000 crabs – should silence them Three-thousand porcelain river crabs clamber over one another in a great red, green and white sprawl of twitching legs and claws. Porcelain sunflower seeds are one thing, crabs another. Good thing they’re not quite real.This is but one small moment in the largest show Ai Weiwei h