Virtual reality technology is making great advances, but it has also helped popularise a theory long debated by philosophers and now gaining supporters in Silicon Valley – that the outside world is itself a simulation

Have you ever wondered if life is not exactly what it’s cracked up to be? OK, let’s take that thought a little further. Have you ever suffered from an identity crisis? Yes? One in which you suspected that you’re not a real person, but instead an extremely sophisticated computer simulation of a real person produced by an immensely more developed civilisation than that which we take to be our own?

It’s just possible that I lost you on that last point, but stay with me, because the reality we take for granted is coming under increasing technological and theoretical threat.

Earlier this month in an office block in Euston, I put on a virtual reality (VR) headset and began playing a prototype of a game developed by a company called Dream Reality Interactive. The company was set up by David Ranyard, the former head of Sony’s VR division.

Ranyard has a PhD in artificial intelligence which he says has been “useless for 19 years”. But he believes there’s going to be a convergence in VR and artificial intelligence (AI) soon, and his company aims to be there when that happens.

There’s a religious element to the notion of a giant simulation, a sense that there is a higher, purer reality

What’s changing is accessibility. Ten years ago VR was the preserve of wealthy “early adopters”. Now you can pick up a reasonable VR set for £600. Ranyard thinks the price will continue to fall, as will the size of the headset, until it becomes more like wearing a pair of glasses.

But right now I’m wearing a large case over my eyes, and headphones. I feel instantly removed from my environment. In front of me I can see a ball, which I can move by looking at a cursor. The ball travels along a high narrow pathway in a vertiginous 3D computer simulation, and I must guide it into various targets to get to the next stages, where a series of ever more fantastic backdrops unfold.

In terms of skill, it is quite simple, but the striking aspect of the game is the physical sensation of playing it. I feel and therefore believe that I am physically moving back and forth, as though I am on a chair on wheels. External reality has fallen away and I am in a strange and compelling world, anxious not to fall off the terrifying precipices. My brain sends signals to my body that create the illusion that it’s shooting around like a pinball, when in fact I am stationary.

So from one perspective it’s just another video game with added thrills. But there’s also something else going on here, a radical change of narrative perspective. Computer games are a form of story, and human beings are devoted storytellers.

As Yuval Noah Harari argues in his book Sapiens, the ability to create binding fictions is what enabled us to become the most dominant species on the planet. And what are stories if not representations, or simulations, of reality?

“I do talks and I have this image of Harold Lloyd [the silent movie star] who’s about to fall off this clock,” says Ranyard. “And the point I make is that in order to care about it, you have to care about him. So part of the film is setting you up to like him. In VR you don’t need to do that set-up because it’s you. There are a whole range of emotions we haven’t used because we’ve always had to do it through empathy.”

Facebook Twitter Pinterest Elon Musk, the man behind the electric car company Tesla, and SpaceX, has said it’s a ‘billions to one chance that we’re not living in a simulation’. Photograph: AP

VR is different because it’s not like a film, in which you watch other people in an invented reality. You are instead the star of what feels like an alternative reality.

Leaving aside the moral implications of this change – and whether it heralds greater self-absorption and social detachment – what is notable, for me, is the aftereffect. It is something of a relief, but also disorienting, to remove the headset and return to the real world. I experience a kind of ontological dissonance, as it takes a few minutes before the familiar returns to its reliable concrete self.

And in that discomfort, that bodily sense of uncertainty, there lies a far more profound and unsettling question. What if the reality I’ve returned to isn’t real but just another, more finely realised simulation? What if the thing our senses – so easily fooled by the headset – tell us is real life are in fact an elaborate creation, every bit as illusory as that I’d experienced on the precarious pathway built out of pixels?

It’s a hoary metaphysical debate that has concerned thinkers as diverse as Descartes, Zhuang Zhou and even, arguably, the godfather of philosophy, Plato. It has also been the subject of countless science-fiction stories, including, most influentially, The Matrix film series. But how can we be sure that reality is real?

In The Matrix, made in 1999 by the Wachowski sisters, humans have been enslaved, paralysed and used as an energy source by advanced machines. But instead of realising their plight, humans are locked in a false reality, a giant simulation created by their machine masters to subdue them.

In essence The Matrix was a reworking of the philosopher Hilary Putnam’s “brain in a vat” scenario, in which a disembodied brain is subject to computer stimulation and operates in a false reality. And in turn Putnam’s vision was an update of the 17th-century French philosopher René Descartes’s first meditation, in which he posited the idea that an evil demon had fabricated the external world.

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For all its philosophical heritage, The Matrix was most of all perfect cinematic fodder for alienated teenagers. But four years after it was released, the Oxford philosopher Nick Bostrom wrote a paper provocatively titled Are You Living in a Computer Simulation?. The paper argued that one of three propositions is true:

a) The human race is likely to become extinct before reaching a “post-human” stage.

b) Any post-human civilisation is unlikely to run a significant number of simulations of its evolutionary history (or variations thereof).

c) We are almost certainly living in a computer simulation.

Known as the simulation argument, it is a wonderful piece of logical projection. There have, naturally, been several critiques of Bostrom’s hypothesis, some on complex logical grounds, and some arguing that creating convincing ancestor simulations will remain impossible.

The hypothesis has attracted the interest and attention of many futurologists and Silicon Valley types. The New Yorker reported last year that two unnamed tech billionaires have gone so far as to employ scientists to work out how to break us out of the simulation.

The appeal of the hypothesis, and its shocking third option (which I explain in more detail below), is partly that it’s a challenge to the basic foundations of our perceptions, but also, paradoxically, that it plugs into some longstanding human preoccupations. Perhaps the oldest human story is that the world and all we see and know is the product of a creator. So there’s a kind of religious element to the notion of a giant simulation, a sense that there is a higher, purer reality, if we could only but grasp it.

(Nicolas Hénin, one of the western hostages held by Islamic State in Syria, reported on his release that one of the jihadis was obsessed with The Matrix, and believed that he had escaped the matrix by going to Syria.)

Back in the real world, or rather back in the possible simulation I take to be the real world, technology advances apace. We are seeing rapid progress in computer science, including the development of quantum computers, whose vastly increased potential capacity would be vital for a large-scale simulation.

At the same time there is continued progress in artificial intelligence, virtual reality, biotechnology and other areas that would help create more convincing simulations. And we can see that with each new breakthrough in technology, we tend to make better, more convincing representations of the world, both now and in the past.

If we assume that these developments continue, and with them our interest in creating simulations of the world, then at some point in the future – 1,000 years, 100,000 years – it’s reasonable to assume that the difference between reality and simulation will become indistinguishable. At which point it will mean we will have created simulated beings with their own consciousness.

But if that is the inevitable outcome of continued technological advancement, unless nuclear war or some other catastrophe intervenes, then it’s quite possible – some would say an overwhelming certainty – that it’s already happened, and we are the ancestor simulations created by an advanced post-human civilisation.

That’s a mind-blowing thought, but it’s one that the tech entrepreneur Elon Musk, for example, has explored. His conclusion is that it’s a “billions to one chance that we’re not living in a simulation [my italics]”.

Musk, the man behind the electric car company Tesla, and SpaceX, which aims to send manned missions to Mars, is not stupid. He’s estimated to be worth about $14bn and that money has come from the commercial exploitation of technological innovations. He is funding a massive global study of AI. He’s a man with his eye firmly fixed on the future and all its rich potential.

So when he says that he believes we are already living in a simulation, it’s not quite the same as, say, David Icke claiming that we are being tyrannised by a secret brotherhood of shape-shifting reptiles. However, rather worryingly, it doesn’t sound all that different. And this is one of the problems with the simulation hypothesis. Although it is a perfectly logical argument, because it is unfalsifiable, it gives rise to all manner of possibilities, many of them as far-fetched as Icke’s villainous lizard people.

Throw in the complications of multiverse theories and you’re looking at a near infinite number of simulated realities, within which there may be countless other simulations, including the one in which I stand in a Euston office block with a headset on, chasing a ball and balancing on a high-rise walkway.

Yuval Noah Harari: ‘Homo sapiens as we know them will disappear in a century or so’ Read more

The simulation hypothesis has entered the culture as an explanatory meme. Writing in the New Yorker earlier this year, the critic Adam Gopnik suggested that the Oscar confusion, in which La La Land was wrongly given the best film award meant for Moonlight, the election of Donald Trump, and the improbable late comeback by the New England Patriots in the Super Bowl showed “that we are living in the matrix, and something has gone wrong with the controllers”.

It was, of course, a lighthearted piece, but it raised a serious point. If we are in a simulation, then is there a possibility that, like any other computer software, it’s prone to glitches? And also could events like the second world war be explained by a programmatic failure, or is whoever is in control of the simulation an evil demon in the Cartesian sense?

(In The Matrix, the machines initially make a utopian simulation, but the humans don’t believe in the reality, so it is adjusted to include all the pain and drama humans associate with being alive.)

Bostrom estimates that there is only a 20% chance that we are living in a simulation. But that isn’t necessarily good news. As Musk likes to point out: “Either we’re going to create simulations that are indistinguishable from reality or civilisation will cease to exist. Those are the only two options.”

Actually there’s a third option, which is that for some reason or other we’ll grow bored with running billions of ancestor simulations, and that virtual reality will become passé.

That’s something to consider while pondering whether or not to splash out on some VR entertainment. In 10,000 years’ time, it might be completely out of fashion.

Five other mind-bending theories

The universe is a hologram

In a nutshell: Everything we see and experience is an illusion. Our 3D reality is encoded on a two-dimensional surface that we cannot see.

Evidence? Earlier this year, scientists from the University of Southampton claimed to have found support for this theory by studying the cosmic background radiation left over from the big bang.

Multiverse theory

In a nutshell: There are infinite universes, including the one we live in. There are various classifications and theories about the types of multiverse that might exist.

Evidence? Although proponents include Neil deGrasse Tyson and Stephen Hawking (who two years ago suggested that there might be an alternate universe in which Zayn Malik had not left One Direction), the theory by its very nature is essentially considered impossible to prove.

Ekpyrotic universe theory

In a nutshell: The big bang was actually a transition from a previous period of contraction to the present period of expansion. The key events that shaped our universe happened before the big bang and the universe is in a constant cycle of expansion and contraction.

Evidence? In 2001, scientists from Princeton University put forward the concept based on unproved ideas from string theory. Though it is still widely rejected, the discovery that the Higgs boson is only 98% of the mass required to keep the universe stable apparently lends the theory some credence.

White holes

In a nutshell: If black holes exist then their opposite must exist too: white holes are thought to be constantly emitting matter and light, letting nothing enter them.

Evidence? There has yet to be any observational evidence of white holes, though a paper published in 2011 posited that the big bang was a white hole and that gamma-ray bursts might also be white holes.

Quantum entanglement

In a nutshell: Two particles can be linked to each other even if separated by billions of light years of space and a change induced in one will affect the other.

Evidence? During the 1930s, Einstein called it “spooky action at a distance” and considered it to be impossible. However, most physicists today accept it to be true. Tara Joshi