A Swedish philosopher at Yale University believes there is a one-in-four chance that we are living inside a computer - like the one in movie smash The Matrix.

Dr Nick Bostrom, who will conduct research at Oxford University later this year, has outlined his ideas in a forthcoming paper submitted to the journal Philosophical Quarterly.

Bostrom said that civilisation will one day simulate consciousness - if it hasn't already - and then go on to simulate universes for artificial consciousness to inhabit.

"If the last possibility is true, then it could already have happened and we are almost certainly living in a simulation," Dr Bostrom said. He estimated the probability at "about 20-25 per cent".

Bostrom believes that, since we are ignorant of the purpose of our world, there is no point trying to impress our "creator".

He said: "The least misleading advice would be to get on with your business as you would have done before."