I woke up in the middle of the night and could not sleep.
Got up to work, figured I’d do some writing. Late at night is a good time for writing.
I went through our blog, reread some old posts, and thought, I am tired of writing tech posts about shallow effervescences of new technology! What I really want to do is draw from my other life as a philosopher and talk about some of the deep and interesting questions virtual reality confronts us with.
Yes, late at night, when there are no distractions, is the perfect time to consider the fundamental truths of the universe, and questions of what is real.
And so, I started a post titled:
Are We Living in a Virtual Reality?
And I began to think:
There’s different interpretations as to what this question might be asking.
1. Are We Plugged Into “The Matrix”?
Are we in The Matrix? A virtual world, embedded in a real world that is very much like this one? Could it be that our “real” brains and bodies, which are very much like our virtual bodies, have had their sensory input subverted or bypassed by humans or humanoid aliens or a human-created artificial intelligence?
Given that we are human-like creatures who are starting to create virtual worlds very much like our own world, meant to subvert our real brain and body’s senses, this possibility suddenly seems much less far fetched than it used to.
One of the more unrealistic things about “The Matrix” is that the simulated reality is so close to actual reality. Human brains are malleable enough that there is no reason this should be true, unless you need backstory for a power fantasy movie plot.
We are still far from being able to hook up a grown human, raised in our culture and with the usual array of senses, into a VR device and have them not know the difference. But even now it is within our technological reach (though not our ethical one) to be able to hook up a human baby to a virtual world in such a way that that they would never, ever, think to question their reality as they grow up.
It would be a reality significantly different from ours; we might have to mostly paralyze them, for example, and sustain their bodies through feeding tube and intravenous fluids, as in The Matrix. But unlike The Matrix, with our current VR technology there can be no sensation of eating, no taste or smell or touch. We’d have to drug them into unconsciousness often, to do VR headset maintenance. A human growing up this way would not question any of this, and they would grow up to be a very different human than anyone our culture has produced.
We’d have to be a cruel society to do it, but it is possible, and if it’s possible, how can we discount that it might be happening to us? The human brain is so malleable. Who says reality isn’t fundamentally different from this, our simulated reality? What difficult-to-simulate senses might we be missing? What but a cruel society would, out of everything the human brain can be, choose this virtual reality for us?
In the Matrix interpretation our perceived world is virtual, but we have an existence outside of this virtual world, real bodies in the “real” world where we actually are. These real bodies need to be physically sustained in order for our virtual selves to survive.
In the related Brain In A Vat thought experiment, there is still a real world with your real brain, but your brain is no longer part of your body. It is your a human brain that once was part of your real human body, and that is the body being simulated, by hooking up your brain to false input (run by a computer, in this case).
In either case, it seems unnecessarily complex that we should need to eat, or breathe, or any other number of virtual actions that in theory should not affect our physical bodies. In the movie The Matrix, if you die in the matrix you die in real life, but the only reason for that “rule” is to up the stakes for the sake of drama.
This question, and idea, existed well before computers, though. In Descartes’s version, the virtual world you live in comes not from an evil scientist outside your virtual world, but an evil demon outside your virtual world. Even earlier, Plato’s allegory of the cave does not require any outer forces of science fiction or fantasy, but is a virtual reality created by humans, different and limited compared to reality (much like our technology today). An important distinction for Plato’s purposes is that the shadows on the wall are of real objects.
Lastly, the Holodeck variation, where our outer non-body senses are being subverted by a simulated reality, but not bypassed. The body we sense is our actual body which is really there, the photons we see are actually hitting our eyes, the forces we feel are actual forces. There’s a few different ways Holodecks “can” work (matter replication, organizing molecules with force beams, magnetic bubbles created by holo-emitters), but in all of them, the virtual part is less about whether things are physical, and more about that their physical existence relies on things outside themselves.
The Matrix variations avoid matters of consciousness. We know our “real” human brains have qualia, conscious experiences of the qualities of things, so as long as our hypotheticals involve a real human brain, we don’t have to ask ourselves hard questions of consciousness.
2. Are We Sims?
Perhaps not only is the world simulated, but we ourselves exist purely as simulations as well. In this case, there is an outside world, but we don’t exist there; we have no real selves to wake up to, or bodies to be reconnected with.
The argument goes something like: “We are capable of making computer simulations of virtual universes, and future humans will be even better. If future humans make simulations of the past, wouldn’t it be an incredible coincidence if we ourselves happened to exist in the real universe, not some higher universe’s simulation?”
In this case, not only are we pure computational objects with no outer existence, but our virtual existence depends on hardware in the real universe (and the simulated simulations between us and them). If the real simulation stops running, we’re gone. But we can also be saved, stored, reset, and run again.
This assumes that it is possible to simulate the human mind, that the brain is itself like a computer. Computationalists are not sure just how it would work, but are pretty sure that features like consciousness just come along with the computations as some sort of macro effect. All we need to do is simulate brain computations, the inputs and outputs, to create an artificial intelligence that will automatically be self-aware, conscious, have qualia, etc.
Computationalism is a fashionable belief these days, probably partly because computers and computational thinking is so new, powerful, and exciting, and partly due to the severe lack of decent scientific conjectures about consciousness.
There’s also plenty of counterarguments. Programming a perfect simulation of behavior does not necessarily imply that the simulation will experience and understand the world. If I were a simulation, it would not be necessary for me to “understand” anything, and yet I do. We currently have no idea how to create artificial consciousness, or what it means to understand something, and there’s no reason to think that our minds are capable of figuring out how to simulate minds anything like ours.
Generally this train of thought has an outside real world that decides to simulate us specifically, as human minds or historical figures from the past. We are created, non-accidental, and exist as individual artificial intelligences. But if forming minds like ours is really hard that lowers the chance of us being simulated, as well as the chance that we exist in the first place.
3. Is The Universe A Computer?
It is not a terribly uncommon view among scientists and mathematicians, especially those involved with quantum physics, to view the substance of the world as being information, or of the universe as being purely computational.
In the computational interpretation of the VR question, we still are “simulations,” in a sense, but there is no outer universe running ours. We’re as real as it gets. Or if there does happen to be an outer universe simulating ours, that universe is also just as computational, and turtles all the way down, so there’s not much point making a distinction.
Given what we know about physics, this starts to make sense. We can’t actually find any “stuff,” and the universe doesn’t behave the way we intuitively think “stuff” should.
Some believe the universe is itself a turing machine, perhaps a giant cellular automaton. Some believe the information is organized differently than in a traditional computer, perhaps contains random elements or continuous things or quantum things. But the common thread is believing there’s nothing else, no “real” reality, just information running itself.
In this view, we are not specifically programmed as artificial intelligences, we just happened to happen. We spiralled into being as an organized subroutine of the computational universe, but don’t have any fundamentally separate self. There is no “real” version of the body, or of the mind.
But if the universe is a giant computer program, what is it running on?
In the formalist view, a computer program has no inherent meaning. When the human mind is outside, writing and running a program, one might say that the human mind creates and attaches meaning, but if no one is outside it, meaning cannot exist (so says the formalist). The realist, on the other hand, might say that the computational universe, like all true mathematical objects, exists in the world independently of the human mind.
I like this question because of its connections to philosophy of math. If the universe is a computer and we experience meaning within it, then mathematical objects exist and have inherent meaning, hooray! But on the other hand, it is no longer fashionable in philosophy of math to view mathematics as pure thing that is fundamentally this or that (and I count theoretical computer science as a type of mathematics); mathematics is much more empirical (or quasi-empirical) than we like to imagine.
Then there’s consciousness. In the second scenario, we thought maybe it would be difficult for a mind to develop a strong AI of itself. But in this case, the Strong AI needs to not only be able to exist purely computationally, but it also must happen by accident as the universe tumbles along its course.
Luckily, even if it’s impossible to simulate consciousness with computation, we can still save the simulation hypothesis. I have witnessed computer scientists follow this logical train of thought to the conclusion that they themselves must not be conscious after all.
4. It’s All A Dream
I’ve written extensively about dreaming’s connection to virtual reality before. We are all capable of running extremely realistic virtual worlds in our heads, and we have no idea how we do this.
Are our brains doing something like a computation, a virtual world program? Just what kind of computation are our brains doing in the first place, even when awake? If what they’re doing can be called “computation” at all?
This is almost the exact opposite of the last scenario. Instead of the world simulating us, we simulate the world. There’s no doubt that there’s a strong sense in which we do indeed experience only a simulated world, just, we often assume that this simulation is based on an outer reality that our senses interpret accurately.
Experiences in dreams can be as real as any real life experience, the perceptions can be just real (in fact, unconstrained by reality, things in dreams can seem even realer than reality). Many philosophers have attempted to make distinctions between real life and dreams: that pain is lessened, or that dreams are more absurd, or that dreams don’t actually exist, or that dreams are not actually experienced, and thus far, science has shut down every objection.
It is not enough, for reality-distinguishing purposes, to say dreams can be like this or tend to be like that. If there is a true distinction between dreams and reality, it needs to distinguish in all cases.
It makes sense that dreams can simulate reality so well, given just how simulated our brain’s version of reality is in the first place. It seems incredibly unlikely that we could tell which is which, and yet we often can, even when dreams are logical or reality is absurd, and we have no idea how.
We have some notion of “reality” and mysteriously believe that dreams do not fit the definition, for reasons which I suspect include causality and permanence and all the other fun things that make some quantum physicists suspicious of “reality”. If it’s impossible to tell whether the reality/dream dichotomy is true, at least we could hope that it’s consistent.
We understand very little about dreaming, but for now the idea of all the world being a dream is not incompatible with the idea that it’s also a computer program. Unlike the computational VR theory, if we are the ones running our own dream program, perhaps we have a real self to wake up to after all.
No matter what the case, this is an area where empirical science has had something to say in response to what was once pure philosophy, which is a good sign that perhaps this is a fruitful area of inquiry, rather than just a philosophical trap.
5. Dream Without Dreaming
If we should consider the world as a computation without an outside computer, perhaps we should consider the world as a dream without an outside dreamer. Or perhaps we’re in a dream, but we’re not the one dreaming it. Either way we’re trapped in a dream but have no self to wake up to.
The idea of a dream without a dreamer doesn’t make much sense to me, as part of my personal definition of “dream” includes that it’s a thing you can wake up from, but I’d like to consider it for the sake of symmetry.
If the universe is computational, then things within our universe such as our minds and dreams are computational. Just as a computational mind can be simulated by a sufficiently powerful computational universe, a computational universe can be simulated by a sufficiently powerful computational mind. Anyone who accepts the possibility of a purely computational universe must also accept the possibility that we are all living in some other sentient being’s dream.
This seems more likely to me than the idea that our minds are being simulated by a standard computer; our own dreams can simulate much more convincing beings than our computers can. Why should we think hypothetical “real” superbeings are any different?
Or perhaps dreams are not virtual worlds separately running in separate heads (whether our own or hypothetical others’), but something else altogether. Perhaps we switch between dreaming and awakening without dreams being contained within a “real world”. Perhaps the perceived difference between reality and dreams is a false hierarchy, and there is no more difference between reality and dreams than there is between a dream and a dream-within-a-dream.
Perhaps Zhuang Zhou was both a butterfly dreaming he was a man and a man dreaming he was a butterfly.
6. All The World’s A Stage
“Real” does not refer only to a technical state of matter or to the perception of physical objects, but also refers to an interpretation of objects or events.
Imagine you’re in a giant reality show where everyone else is an actor and all the objects are props. It’s not that the existence of the world is not real, but that the meaning of the world is not real.
We have an idea of what it means for people to be “genuine” or “just acting”, though it’s not clear to what extent this is a hard distinction and that all human behavior is not, in some way, a performance.
It is fun to imagine that a couch, as part of a set of a living room on stage, is merely acting like a couch. In a systems view, one might view the definition of objects as relying on their context in the greater “living room” and “household” system, rather than the structure of their physical (or informational) matter.
This argument might require meaning and reality to come from the human mind, and if there’s more in the world than the human mind (as would be the case if we’re living in a computational world rather than the dreamer of the world) it is extra difficult to account for where that meaning comes from.
But truth is fuzzier than we like to pretend, even when meant in a mathematical sense. Somehow it seems progress in human knowledge increase our understanding, without ever once increasing what we know for certain.
Also relevant to this post are things like solipsism, the Buddhist concept of Maya, and the common religious idea that there is a realer world waiting for us once we leave this one, but it’s about time we got to the answer.
So, back up to the outer story, in which I cannot sleep and begin writing this post (It’s the same story, of course, just as all stories-within-stories are plot devices more than true structural differences. You can exit Hamlet without separately first exiting the Mousetrap, just as you can wake up directly from a dream-within-a-dream-within-a-dream without having to wake up separately through each member of the stack).
It’s one thing to understand a theoretical possibility, but it’s another to immerse your brain in a worldview where this theoretical possibility becomes an actual possibility.
And so I tried to do just that. I leaned back and tried to really grok it, the way that if we were in a virtual world then the real world might be nothing like this one, that our bodies and perceptions might be nothing like they are here, that in fact the harder reality is to simulate the more likely it is we’re trapped within whatever’s easy. I tried to believe in the technology we’re creating, and will continue to create, that suddenly makes all this seem possible, in the same way that Mars rovers and SpaceX launches make the old science fiction of humans on Mars suddenly seem not just potentially plausible, but a definite part of the future of humanity.
And after a few minutes, I started to get it. Really get it. I could feel it.
I asked myself: Are we living in a virtual reality?
And to my vast surprise, a great conglomerate of robotic voices speaking directly into my head answered:
In the first split second when my brain disconnected from my body, all I could think was that somehow, I must have grokked unreality hard enough that the universe had answered by pulling me back to reality, and that was exciting!
Sight went first, then every other sense. I could not move my body or feel my body because I no longer had a body.
I was being pulled.
My formless self switched to wordless thoughts; strange how much my ability to think in english words seems to happen in my mouth (which I no longer had) rather than my mind (which, at this point, I could feel separating from the fabric of the universe with a growing vibration).
In the second split second, excitement turned to apprehension. Whatever was happening, it felt potentially irrevocable, and perhaps I should not tear my mind out of the fabric of the universe just because some robotic conglomerate voice was still echoing in my head?
Which, I realized, could not possibly be real. In fact, this sensation, of being entirely disconnected from all senses and physical form, was not entirely unfamiliar to me; I had felt it in dreams before. Which, quite obviously now, is what this was. I must have fallen asleep when I’d laid back to grok. It made sense, that I’d been thinking so hard about all this stuff, and then fell asleep and dreamed about it.
And so I woke up, still in the void, and did what I did in all those dreams long ago– wait in the void to get my body back. And then, once I did, wait some more in sleep paralysis before being able to move it.
The eyes open first.
I realized, in those moments of waiting, that I hadn’t just fallen asleep while trying to grok the potential virtuality of the world, I’d been dreaming the whole time. I dreamed I couldn’t sleep. I dreamed I got up and read old blog posts. And I was dreaming when I typed out the title:
Are we living in a virtual reality?
The truth, the actual real answer to my question, was that the world is indeed not real, and that the manner in which it isn’t real is option 4, “it’s all a dream.”
You may not be satisfied with this as being the true answer to the original question. I am not satisfied with how, even though my understanding of the question and all it refers to has not changed, even though I am capable of self-awareness and logical thought while dreaming, even though my dream was perfectly coherent and realistic (up unto a point), that the answer to the question should change independent of my understanding of it.
It would be nice to have a question and answer that doesn’t change based on tautology (“I was in a dream therefore the answer was I was in a dream, but now I am in reality so the answer changed to being it’s real”). If the answer has changed, the question is an empirical one, and pure reasoning alone is not enough to answer it. If the answer has not actually changed, either I was originally right and am still in a dream, or I was wrong about that part and perhaps actually was being pulled back into reality by my computational overlords, and in my moment of fear I missed my chance.
No matter the case, it’s experiences like that that remind us not to take reality for granted.
Personally, I suspect that, as with many things, our understanding of the question is wrong to begin with. Perhaps, just as we perceive there to be dreams-within-dreams and plays-within-plays where there are only plays and dreams, perhaps we perceive a virtual reality where there is only the same old meat brain struggling wildly to turn a vastly complicated universe into this organized story that we call “reality”.
1. “The Matrix”, as in the 1999 movie. Relevant to this discussion is that people’s real bodies are just like their virtual ones, and the virtual reality is just like the real world of 1999.
2. See Hilary Putnam’s “Brains in a Vat” chapter in Reason, Truth, and History for more Brain in a Vat fun! Putnam argues we cannot be “brains in a vat” because we are only capable of referring to things in our perceived universe, therefore “brain in a vat”, in the only sense that could refer to an outer universe, fails to refer.
3. René Descartes, Meditations on First Philosophy. Translated as “Evil Genius” in the linked version. Descartes’ famous “I think therefore I am” comes from the Evil Demon thought experiment. The more metaphorically inspirational version:
“He can never cause me to be nothing so long as I think that I am something.” -Descartes
4. Plato’s allegory of the cave, in Book VII of The Republic. This is what “Cave Automatic Virtual Environment” (VR using a room full of projectors) references.
5. The distinction between “real” matter and matter that is made out of, like, particles and forces, kind of implies that in the Star Trek universe matter is really real and not itself a simulation or computational object. Also you can apparently have a holodeck within a holodeck. See Joshua Bell’s Holodeck FAQ for everything you ever wanted to know about holodecks.
6. Nick Bostrom has a more rigorous treatment of this question in “Are You Living in a Computer Simulation?”
7. Based on the above, Phil Torres argues that with so many simulations going on, there’s a quite a high likelihood we’re about to wink out out of existence. This assumes that there’s not just a higher society simulating us, but stacks of simulated societies simulating societies.
8. John Searle calls AI with full consciousness and qualia “Strong AI”, and AI that behaves convincingly human but without self-awareness “Weak AI”.
9. Hilary Putnam is one of the originators of the Computational Theory of Mind, which states that the mind works essentially like a big fancy computer. See “Mind, Language, and Reality”. Putnam is also one of its major disputers, but the idea has caught on.
10. See John Searle’s “Chinese Room” thought experiment, originally published in “Minds, Brains, and Programs”.
11. Steven Wolfram’s “A New Kind of Science” is a beautiful book on cellular automata, which also contains a thorough covering of the view that the universe is purely computational in a discrete, turing-machine-like fashion.
12. Brian Whitworth uses this argument to say that if the universe is simulated, there is an outside simulator. In “The Emergence of the Physical World from Information Processing” he argues that if the universe were simulated, it would explain many strange quantum effects (like, the speed of light is simply due to the refresh rate). By turtle-avoidance, this would imply that the outside universe has nice simple intuitive physics, which does have its appeal.
13. “New Directions in the Philosophy of Mathematics”, ed. Thomas Tymoczko, is a great diverse collection of papers that quickly get past the old paradigms of foundationalism to fun new stuff. (Make sure you get the expanded edition!)
14. “Lucid Dreams: The Original Virtual Reality” by Vi Hart. <— that’s me! 😀
15. Locke argued that pain cannot be as sharp in dreams as in real life. Turns out he was wrong, but his legacy lives on as every day people pinch themselves in real life for no scientific reason.
16. Hobbes thought the difference is that real life is not absurd. There may be a strong correlation, but that’s not the thing that differentiates them. Dreams can be extremely coherent, and as for life not being absurd, I’d like Hobbes to get together with Camus on that…
17. Norman Malcolm’s “Dreaming” and “Dreaming and Skepticism” has some very interesting ideas about dreaming, including that you cannot verify that a person is ever dreaming because dreamers cannot communicate to the outside world, dreams do not actually exist, and all dream reports are false memories made upon waking. Now we have scientific data on all that and know he was wrong, but it was a fascinating way to try to circumvent Descartes’ Evil Demon. Fight skepticism with skepticism!
18. Daniel Dennet, following Malcolm, laid out his own version of skepticism against dreaming in “Are Dreams Experiences?” with the answer “No”. The argument has many interesting things to say about the nature of memory and experience. It is true that one can “remember” things that one did not actually experience, and that this happens more often in dreams than waking life, but contra Dennet, it is not true for all dreams. Those practiced in dream recall call these “false memories,” and are fairly good at distinguishing them from the experienced part of dreams. It’s quite an interesting phenomenon and well worth both philosophical and scientific attention.
19. Zadra et al, The Nature and Prevalence of Pain in Dreams. Basically, pain in dreams often mirrors what you’d expect in real life. Not always, but definitely not a hard separator between dreams and reality.
20. Stephen LaBerge has done a number of interesting experiments involving tracking eye movements (which can be controlled in dreams) to allow lucid dreamers to communicate out from dreams as they are having them. “Lucid Dreaming: Evidence that REM Sleep Can Support Unimpaired Cognitive Function and a Methodology for Studying the Psychophysiology of Dreaming” shows some examples of people carrying out experiments in their dreams, and communicating out through EEG signals. This doesn’t prove that cognitive function is entirely unimpaired, but it does provide evidence consistent with reported experiences, and a methodology for learning more.
21. I mean, we call it “Lucidity,” and we know that it happens, but not how it happens. I find my own sense of lucidity to be completely dependable at distinguishing between dreams and reality, when I bother to employ that sense. But I have no idea how that sense brings back the correct answer. I could guess, though, that something in my brain knows whether it’s creating a world with or without the help of sense data, and that someday we’ll know more.
22. Bertrand Russell, in “The Problems of Philosophy”, immediately capitulates to the dream argument in one sense, saying that sure, there’s no way to tell if life is not a dream, and then concludes that therefore there’s no particularly good reason to complicate the world by thinking it is, so, Occam’s Razor it and get on with your life.
23. Zhuang Zhou’s butterfly dream:
Once Zhuangzi dreamt he was a butterfly, a butterfly flitting and fluttering around, happy with himself and doing as he pleased. He didn’t know he was Zhuangzi. Suddenly he woke up and there he was, solid and unmistakable Zhuangzi. But he didn’t know if he was Zhuangzi who had dreamt he was a butterfly, or a butterfly dreaming he was Zhuangzi.
24. I’m thinking of the 1998 movie The Truman Show, where Truman finds out his life is “fake”, a reality show created for the benefit of its viewers. It’s not uncommon for children to imagine that perhaps there are hidden cameras, or aliens, or otherwise they are being watched all the time, and that everything that happens is planned for the benefit of the story. Sometimes this persists in adults, and in the case of reality shows, is informally called the Truman Show delusion.
25. Penelope Maddy has this great concept of “The Second Philosopher” (in opposition to Descartes’ “Meditations on First Philosophy”), a cross-discipline thinker who approaches knowledge from an outside empirical perspective, often to arrive at the same truths we imagine are gained rigorously. Quite fittingly, she explains this worldview by giving examples of the behavior of the Second Philosopher, rather than trying to define it. “Second Philosophy” (this links to a short paper, not to be confused with her later book of the same title) describes this viewpoint, but those with a background in mathematics and logic will enjoy her more technical papers.