Artificial intelligence: how clever do we want our machines to be?

From 2001: A Space Odyssey to Blade Runner and RoboCop to The Matrix, how humans deal with the artifical intelligence they have created has proved a fertile dystopian territory for film-makers. More recently Spike Jonze's Her and Alex Garland's forthcoming Ex Machina explore what it might be like to have AI creations living among us and, as Alan Turing's famous test foregrounded, how tricky it might be to tell the flesh and blood from the chips and code. These concerns are even troubling some of Silicon Valley's biggest names: last month Telsa's Elon Musk described AI as mankind's "biggest existential threat… we need to be very careful". What many of us don't realise is that AI isn't some far-off technology that only exists in film-maker's imaginations and computer scientist's labs. Many of our smartphones employ rudimentary AI techniques to translate languages or answer our queries, while video games employ AI to generate complex, ever-changing gaming scenarios.