Friday, April 22, 2022

Let's Hope We Don't Live in a Simulation

reposting from the Los Angeles Times, where it appears under a different title[1]


There’s a new creation story going around. In the beginning, someone booted up a computer. Everything we see around us reflects states of that computer. We are artificial intelligences living in an artificial reality — a “simulation.”

It’s a fun idea, and one worth taking seriously, as people increasingly do. But we should very much hope that we’re not living in a simulation.

Although the standard argument for the simulation hypothesis traces back to a 2003 article from Oxford philosopher Nick Bostrom, 2022 is shaping up to be the year of the sim. In January, David Chalmers, one of the world’s most famous philosophers, published a defense of the simulation hypothesis in his widely discussed new book, Reality+. Essays in mainstream publications have declared that we could be living in virtual reality, and that tech efforts like Facebook’s quest to build out the metaverse will help prove that immersive simulated life is not just possible but likely — maybe even desirable.

Scientists and philosophers have long argued that consciousness should eventually be possible in computer systems. With the right programming, computers could be functionally capable of independent thought and experience. They just have to process enough information in the right way, or have the right kind of self-representational systems that make them experience the world as something happening to them as individuals.

In that case, the argument goes, advanced engineers should someday be able to create artificially intelligent, conscious entities: “sims” living entirely in simulated environments. These engineers might create vastly many sims, for entertainment or science. And the universe might have far more of these sims than it does biologically embodied, or “real,” people. If so, then we ourselves might well be among the sims.

The argument requires some caveats. It’s possible that no technological society ever can produce sims. Even if sims are manufactured, they may be rare — too expensive for mass manufacture, or forbidden by their makers’ law.

Still, the reasoning goes, the simulation hypothesis might be true. It’s possible enough that we have to take it seriously. Bostrom estimates a 1-in-3 chance that we are sims. Chalmers estimates about 25%. Even if you’re more doubtful than that, can you rule it out entirely? Any putative evidence that we aren’t in a sim — such as cosmic background radiation “proving” that the universe originated in a Big Bang — could, presumably, be simulated.

Suppose we accept this. How should we react?

Chalmers seems unconcerned: “Being in an artificial universe seems no worse than being in a universe created by a god” (p. 328). He compares the value of life in a simulation to the value of life on a planet newly made inhabitable. Bostrom acknowledges that humanity faces an “existential risk” that the simulation will shut down — but that risk, he thinks, is much lower than the risk of extinction by a more ordinary disaster. We might even relish the thought that the cosmos hosts societies advanced enough to create sims like us.

In simulated reality, we’d still have real conversations, real achievements, real suffering. We’d still fall in and out of love, hear beautiful music, climb majestic “mountains” and solve the daily Wordle. Indeed, even if definitive evidence proved that we are sims, what — if anything — would we do differently?

But before we adopt too relaxed an attitude, consider who has the God-like power to create and destroy worlds in a simulated universe. Not a benevolent deity. Not timeless, stable laws of physics. Instead, basically gamers.

Most of the simulations we run on our computers are games or scientific studies. They run only briefly before being shut down. Our low-tech sims live partial lives in tiny worlds, with no real history or future. The cities of Sim City are not embedded in fully detailed continents. The simulated soldiers dying in war games fight for causes that don’t exist. They are mere entertainments to be observed, played with, shot at, surprised with disasters. Delete the file, uninstall the program, or recycle your computer and you erase their reality.

But I’m different, you say: I remember history and have been to Wisconsin. Of course, it seems that way. The ordinary citizens of Sim City, if they were somehow made conscious, would probably be just as smug. Simulated people could be programmed to think they live on a huge planet with a rich past, remembering childhood travels to faraway places. Their having these beliefs in fact makes for a richer simulation.

If the simulations that we humans are familiar with reveal the typical fate of simulated beings, long-term sims are rare. Alternatively, if we can’t rely on the current limited range of simulations as a guide, our ignorance about simulated life runs even deeper. Either way, there are no good grounds for confidence that we live in a large, stable simulation.

Taking the simulation hypothesis seriously means accepting that the creator might be a sadistic adolescent gamer about to unleash Godzilla. It means taking seriously the possibility that you are alone in your room with no world beyond, reading a fake blog post, existing only as a short-lived subject or experiment. You might know almost nothing about reality beyond and beneath the simulation. The cosmos might be radically different from anything you could imagine.

The simulation hypothesis is wild and wonderful to contemplate. It’s also radically skeptical. If we take it seriously, it should undermine our confidence about the past, the future and the existence of Milwaukee. What or whom can we trust? Maybe nothing, maybe no one. We can only hope our simulation god is benevolent enough to permit our lives to continue awhile.

Really, we ought to hope the theory is false. A large, stable planetary rock is a much more secure foundation for reality than bits of a computer program that can be deleted at a whim.


In Reality+, Chalmers argues against the possibility that we live in a local or a temporary simulation on grounds of simplicity (p. 442-447). I am not optimistic that this response succeeds. In general, simplicity arguments against skepticism tend to be underdeveloped and unconvincing -- in part because simplicity itself is complex to evaluate (see my paper with Alan T. Moore, "Experimental Evidence for the Existence of an External World"). And more specifically, it's not clear why it would be easier or simpler to create a giant, simulated world than to create a small simulation with fake indicators of a giant world -- perhaps only enough indicators to effectively fool us for the brief time we exist or on the relatively few tests we run. (And plausibly, our creators might be able to control or predict what thoughts we have or tests we will run and thus only create exactly the portions of reality that they know we will examine.) Continuing the analogy from Sim City, our current sims are more easily constructed if they are small, local, and brief, or if they are duplicated off a template, than if each is giant, a unique run of a whole universe from the beginning. I see no reason why this fact wouldn't generalize to more sophisticated simulations containing genuinely conscious artificial intelligences.


[1] The Los Angeles Times titled the piece "Is life a simulation? If so, be very afraid". While I see how one might draw that conclusion from the piece, my own view is that we probably should react emotionally as we react to other small but uncontrollable risks -- not with panic, but rather with a slight shift toward favoring short-term outcomes over long-term ones. See my discussion in "1% Skepticism" and Chapter 4 of my book in draft, The Weirdness of the World. I have also added links, a page reference, and altered the wording for clarity in a few places.

[image generated from inputting the title of this piece into's steampunk generator]


SelfAwarePatterns said...

It seems like the simulation scenario can't be ruled out. Although my credence in it is below 10%.

I do think the parsimony argument has traction. Reality is the world as revealed by our best scientific theories, or it's a simulation of such a world. The simulation seems like an extra assumption. Occam's Razor seems to favor the first option.

Of course, that's just a heuristic, and reality is likely much broader than our theories. But that leaves open a vast array of possibilities, of which a simulation is an infinitesimal slice. What chance is there that it's the right guess?

If I recall correctly, Chalmers thinks the idea of a perfect simulation undercuts this argument. Maybe there are far more simulated universes than real ones. Although I think he (and Bostrom) accept the idea of a perfect simulation far too easily.

But maybe the simulation is making me think that.


Kaplan Family said...

maybe we live in a simulation designed by benevolent therapists to help bring us to our best selves. Is there any reason to think this is more or less likely than capricious gamers?

Gene Glotzer said...

I've never read much about the simulation arguments. I'm wondering, though, do they ever address point of view? It seems a little silly to say it's a simulation from our point of view, so why should we prioritize the creator's point of view?

Philosopher Eric said...

I can see why you’d be uncomfortable with the “Be afraid” warning that the LA Times attached to your essay professor. Clearly a hook to get people to read was important to them, and even if you didn’t mention reason for fear. Surely they wouldn’t have been happy to include the postscript you did here suggesting that this simulation business is probably wrong.

Should a person at least hope that he/she doesn’t live in a simulation given that it might be turned off and so not continue to generate the code that exists as his/her qualia? I suppose at least if that qualia tends to feel good. As you know I consider the “sims” premise to depend upon magic. It’s something that I mean for us to not get into until after the publication of your coming “Weirdness” book. Happy to hear that the book is progressing!

Patrick S. O'Donnell said...

Eric, I commented on your LA Times article on my FB page and am sharing the link because it is too long to post here. In a day or two I will post it on my blog, ReligiousLeftLaw, which will contain a number of embedded links. You might also be interested in my latest post there on some of Alan Turing's arguments about AI. Thanks for motivating this provocative discussion.

Arnold said...

My 9 and 7 year old grand children are playing board and screen games as part of their education and from this "Let's Hope We Don't Live in a Simulation" post...
...I am inspired, to as best I can, influence my children and gand children to teach themselves, to learn, to sit quietly every morning in hope, to grow and sustain an inner life, to be more than equal to sim living...

Callan said...

What's the profit in running those simulations? It seems to be building up a threat based on a complete waste of energy?

I think you'd be better off with you're a real person with suppressed memories in a simulation - the whole 'reincarnation' thing is people failing to have their memories suppressed properly and are remembering previous 'lives'. Possibly the sort of games immortals play to rekindle the fires of living a mortal, finite life and having to burn bright in the time the mortals have. What are the odds of being a dreadfully bored immortal who cast aside memory to plunge into a simulation of the distant past?

Jim Cross said...

I would suggest that the simulation question falls into a category of questions that are meaningless, akin to the "why is there something rather than nothing" question.

Patrick S. O'Donnell said...

The post I promised is now up, should Eric or anyone else be interested:

Matti Meikäläinen said...

Might we achieve some insight with a slightly different focus to this speculation? Would it be helpful to understand the human motivations that inspire some to postulate reality as an elaborate simulation? What needs, desires, and human purposes inspire such a hypothesis? Looking at it in another way, how would one draft a scientific research proposal on such a hypothesis? I submit one could not. So, if this belief becomes mainstream over time will we then get some future Daniel Dennett writing a book about breaking the spell? As the French say: plus ça change, plus c’est la même chose.

Eric Schwitzgebel said...

Hi folks! Sorry about the slow reply. Last week was chaotic and I forgot to check the blog comments.

SelfAware: Yes, I do think that one starts considering skeptical cosmological scenarios in general, many others also open up. But our credences in them presumably remain small.

Gene: I don’t think it’s a matter of point of view, but instead a matter of whether beneath the reality we see is a computational reality very different in character, yes?

Phil E: Yes, that seems right.

Patrick: Thanks for the link! I’ll check it out.

Call an: Right, who knows? If there are high tech civilizations anything like ours, the citizens might run simulations for fun or to rekindle memories as you say — or to simulate history, or for science or…?

Matti: Yes, I agree that a cultural critique of why this hypothesis is attractive to some people could be very interesting!

Arnold: Right, carry on either way!

Call an: