The Economist and the Contemporary Art Society have teamed up to bring sculpture to the heart of the city. For the next three months, London-based Chilean artist Fernando Casasempere's impressive, mechanised installation The Thought-Provoking Machine provides Londoners with something additional to chew on over their lunch hour. Casasempere takes his inspiration from the troublesome relationship between machinery and natural resources: using two industrial conveyor belts, he taps into the power of mass production and invokes its negative impact on the natural world.