What is reality?

In the 2010 remake of the movie Tron, a computer programmer is trapped in his own digital creation for 20 years where he battles an evil genius and rides sleek jets and super-cars that defy physics. It is, of course, only a movie.

But the mundane and the marvellous may soon be indistinguishable, said the award-winning director James Cameron at the Abu Dhabi Media Summit. He predicted a revolution in 3D digital technology that will immerse users to the point that it becomes their reality.

But what is reality? With reality TV, the ability of viewers to discern what is real from what is fantasy has diminished. Such cultural icons as Shilpa Shetty and Ozzie Osborne loom large in too many minds. Probably the first reality TV was pro-wrestling in the 1950s but that was something for children to believe in. A sign of growing up is realising that those howling behemoths on the wrestling mat are play acting - and so are most "reality" TV stars.

Such adult scepticism is also needed in the whizz-bang world of 3D reality that is migrating from the cinema to TV and video games. Observed the techno-wizard Cameron: "I think that when you start layering stereoscopic 3D in with gaming, people's minds will literally just go through that screen."

Which is exactly what happened to the hero in Tron.