Both Alien and its sequel Aliens, which Prometheus is said to be a prequel to (although Ridley Scott has disputed this, only conceding that the films all inhabit the same universe), included androids in their crew.
But in Prometheus, the android's story is shifted more to centre, focusing on what defines humanity, and whether a robot can ever hope to achieve it.
As the film critic Mark Kermode said, "Michael Fassbender [on scene-stealing form as David] is really the centre of the movie. And in fact it is clearly that Scott is less interested in making an Alien prequel than he is in building up to the ideas of Blade Runner, Blade Runner being about what does it mean to be human if you are an android."
|One android (possibly two) in Ridley Scott's Blade Runner.|
But as Prometheus co-writer Damon Lindelof says, David "is not interested in being a real boy. In fact, he just comes out and says that he mimics emotions effectively, but he does not have emotion".
Turning to the science of artificial intelligence (AI) and robotics, given that the year the Prometheus mission sets off is around 2090, that gives us less than 78 years to create an android with the advanced intelligence and physical capabilities of David. Perhaps a little ambitious, but then again, 78 years ago we didn't have the internet, mobile phones or space flight, so maybe it's not so unrealistic.
At the moment, though, AI is struggling to make the leap to reach human levels of intelligence. As Sally Adee writes in New Scientist,
"AI started with the glimmering sci-fi promise of machines that looked, spoke, felt and acted like humans. It seemed at one brief point as if computers networked in the right way would produce realistic simulations of the human mind. But machines weren’t up to the task, and AI crumbled into pragmatism. We can see the results all around us: machine intelligences that play chess, navigate autonomously and sort our email, but fail to evoke any human emotion except perhaps frustration."What we do have, however, are humanoid robots that can dance, recognise faces, mimic facial expressions and pick up a ball, all of which could be seen at the Robotville exhibition at the Science Museum in London last year.
And in the Economist's Technology Quarterly supplement last week, robotics are clearly making great strides forward - military robots ranging from the Sand Flea, which can leap through a window nine metres up, to the LS3, a dog-like robot that can trot behind humans while carrying 180kg of gear, show the impressive variety of shapes and capabilities that exist right now.
The Economist piece also tackles an important question of "robot ethics":
"As they become smarter and more widespread, autonomous machines are bound to end up making life-or-death decisions in unpredictable situations, thus assuming - or at least appearing to assume - moral agency. Weapons systems currently have human operators 'in the loop', but as they grow more sophisticated, it will be possible to shift to 'on the loop' operation, with machines carrying out order autonomously.
"As that happens, they will be presented with ethical dilemmas. Should a drone fire on a house where a target is known to be hiding, which may also be sheltering civilians? Should a driverless car swerve to avoid pedestrians if that means hitting other vehicles or endangering its occupants?"These questions would need to be resolved before androids could ever become commonplace.
We also have androids acting in plays - performances of Android-Human Theatre: Sayonara feature a robotic woman co-starring with a human in a play about a dying girl's relationship with her android companion.
But until computers can achieve much greater levels of AI, androids like David will be a long way off. Or perhaps they may never happen at all. As Hiroshi Ishiguro, director of Osaka University's Intelligent Robotics Laboratory, told Scientific American, androids will never be able to pass for humans, saying: "It's impossible to have the perfect android."
There are plenty of other issues to explore regarding the plausibility of the science in Prometheus (of course remembering that this is science fiction, with the emphasis on fiction) - Charles Day's blog over on Physics Today does a good job of exploring them, and is definitely worth a look.