Even by the standards of London’s fast-moving contemporary art scene, the last week has been an extraordinary one. First, there was the completion of Antony Gormley’s “One & Other” project on the Fourth Plinth of Trafalgar Square. This allowed members of the public to take over the space for an hour each over the course of 100 days, and do whatever they pleased with their 60 minutes of prominence.

Then it was down to more serious business. No sooner had the last temporary hero stepped off the plinth than the Frieze art fair pitched into town, with the improbable assortment of curious millionaires and cutting-edge conceptualists that has helped make contemporary art one of the most lucrative growth areas of the world economy over the last decade.