For the last five years, philosophers, mathematicians and physicists have been debating a modern reworking of a theory that has been around for hundreds of years. How do we know that reality is, in fact, truly reality? How do we deonte “reality”? How could we tell if reality was, in fact, a simulation? What would we do if we were in a “Matrix”? And what would it mean for the concepts of God and free will? dogsounds investigates.
For many decades, philosophers have mulled over the “brain-in-a-vat” argument, and what it means. Simply put, the argument hypothesizes a scientist who has extracted a human brain and placed it, still alive and fully functional, into a vat where it can be stimulated in all the ways that a brain is, normally. The scientist has technology that allows him to recreate stimuli to suggest to the brain that it is in a living, breathing world. From the unfortunate envatted brain’s point of view, this stimulus means that it sees, hears, smells, feels and touches an outside world that, for all intents and purposes, is real. It has no idea at all that it is sitting in a jar in a lab.
This theory of the envatted brain has fuelled many discussions about the nature of reality and of our beliefs in that reality. As far as the brain is concerned, assuming the simulation is flawless, then there would be no way for the brain to know that it was in fact, in a jar. In fact, the argument deepens and states that in reality (no pun intended) this inability to secure evidence either way means that the the whole issue of “reality vs. envatted” can never be resolved from the individual point of view.
This postulation has appeared in most philosophical discussions of reality, most prominently in the theories of philosophical skepticism and solipsism. In essence, the postulation dates back many hundreds of years, albeit in differing forms. After all, 17th Century philosophers would not have been able to put a scientist or a supercomputer in there!
However, over the years, it has raised many interesting and and often unanswerable questions. But in 2003, philosopher Nick Bostrom looked at the issue again – and factoring in knowledge about technology and computing power, realised that the issue itself is, in fact, much more far-reaching, calling into question not just our own personal perception of reality, but also the idea of free will and the concept of an over-reaching creator – God – and what form he may or may not take.
Bostrom coined the phrase “ancestral simulation” and revisited not just the hypothetical scenario itelf, but whether such a scenario would be possible, technologically. And why it would happen. And in doing that, he opened up a whole can of philosophical worms.
Firstly, Bostrom knew that the “envatted brain” scenario was nonsense, logistically. It may be feasible that a scientist keeps a single or small number of brains in such a state, but the feasabiilty of the whole human population being so trapped is highly unlikely – there would be no tangible reason to carry out such a monumental and expensive task. He jokes that the Matrix trilogy of films use just this principle, but that the reason for doing so – is utterly silly:
Why the Matrix? Why did the machines do it? (Human brains may be many things, but efficient batteries they are not.) Bostrom, Why Make A Matrix? And Why You Might Be In One
He posits that, yes, there may be reasons for such an endeavour, but it is not likley that it would be done in such a physical and energy-consuming and labor-intensive way. Instead, he theorized that although the envatted brain idea is ridiculous, the idea that a reality could be simulated for historical, research or some other purpose is not. In fact, as he developed his theory, he began to realise that, statistically speaking, there is a good chance that such a simulated reality is not impossible, and that, by progressing his ideas forward there is in fact almost no way to refute the idea that we are, in fact, currently simulated. Theoretically, you, me, this text, your computer, your room, the people in other rooms and everything that exists to our senses could, in fact, be utterly virtual. However, although he does not believe the feasability of the envatted brain scenario, his theory does agree with one aspect of it – there would be no way to tell whether the reality we perceive is “real” or “virtual”.
In part two we will look in more detail at Bostrom’s ideas about why Ancestral simulations would be created, and whether there is anything preventing such an endeavor.
In part one we looked at the basic shape of the theory of Ancestor Simulation. In part 2, we will take a closer peek at philosopher Nick Bostrom’s postulation and see the framework of logic that is its foundation.
We saw how Bostrom realised that the “brain in a vat” hypothesis was impractical, but that the idea of a simulated reality itself was not. He began to see that although the method was unfeasible, the concept that, for one reason or another, an “Architect” could create a wholly virtual reality in which the inhabitants believe that the reality they perceive is “really real” was not impossible and would be very hard to refute.
But what led Bostrom to this conclusion?
Simply put, rather than looking at the “why” of Ancestor Simulation, he looked at the “how”. And he began to theorise that, with certain assumptions as to technological advancement and the path that our descendants will take (assuming they are real), there are only three ways our future can pan out. And that these three paths we may follow will, more or less, determine whether we are, in fact, living in a simulation right now. But, firstly, we have to ask could such a creation be possible, and if so, why make one? This gets mathematical from here in, so bear with me!
Much like the scientist with the envatted brain, Bostrom’s theory has a protagonist. He uses a sufficiently advanced future posthuman civilization who have the technological capability and desire to simulate not only a conscious thinking entity via artificial means, but the entire world in which that entity lives. Furthermore, he suggests that the motivation and effort involved in such a simulation would mean that the posthuman civilization would be more likely to produce not just one entity in a world full of “mindless bots” – that the target entity cannot distinguish from itself – but rather the entire sentient civilization in which that entity exists, and the universe around it, to a varying level of granularity. He suggests that one possible reason for such an endeavor could be for the posthuman society to simulate and study its own history through recreation of their ancestors, or (as they would have sufficient computing power) to simulate multiple or even infinite histories and outcomes, to either see “what would have happened if…?” or, more plausibly perhaps, to simply ensure greater success of achieving the one, true history. Further, It is not impossible that, given such technological prowess, the posthuman civilization could create such a simulated universe for simple entertainment – Truman Show style – or as a “game” in which the posthumans can inject themselves at will. There is nothing to say that such a posthuman society would have the same ethical mores or desires as ours. He assumes that creating the entire synaptic pathways of every living organism in the target civilization is within the means of the protagonist.
Of course, this is all dependent on two factors: the possibility of being able to harness such technology, and the ability to successfully and artificially simulate a thinking, conscious mind.
Wire The Sucker Up!
Our current understanding of physics and computing technology means that right now, there is no way we could ever simulate a conscious mind. Some experts feel that given the ever increasing rate of technological advancement, such a feat may be only decades away. Others think that this process may take hundreds or even thousands of years. Either way, most experts would agree that at some point, we will reach that level of sophistication. Such a process is discussed in the next section below. But for the moment, let us assume that are destined to be able to acheive such a level of computing power.
Bostrom explains in his 2003 paper Are You Living In A Computer Simulation that the limits of current knowledge about physics and technology render us unable to make a confident estimate of the possible upper limits of future computing power. Currently lacking a unified theory of everything, it is unclear what amazing discoveries in quantum physics may allow us to “transcend those constraints that in our current understanding impose theoretical limits on the information processing attainable in a given lump of matter.” Instead, we can only use our current knowledge to impose lower limits of future computing power. From the 2003 paper:
For example, Eric Drexler has outlined a design for a system the size of a sugar cube (excluding cooling and power supply) that would perform 10^21 instructions per second. Another author gives a rough estimate of 10^42 operations per second for a computer with a mass on order of a large planet. (If we could create quantum computers, or learn to build computers out of nuclear matter or plasma, we could push closer to the theoretical limits. Seth Lloyd calculates an upper bound for a 1 kg computer of 5*10^50 logical operations per second carried out on ~10^31 bits. However, it suffices for our purposes to use the more conservative estimate that presupposes only currently known design-principles.)The amount of computing power needed to emulate a human mind can likewise be roughly estimated. One estimate, based on how computationally expensive it is to replicate the functionality of a piece of nervous tissue that we have already understood and whose functionality has been replicated in silico, contrast enhancement in the retina, yields a figure of ~10^14 operations per second for the entire human brain. An alternative estimate, based the number of synapses in the brain and their firing frequency, gives a figure of ~10^16-10^17 operations per second. Conceivably, even more could be required if we want to simulate in detail the internal workings of synapses and dendritic trees. However, it is likely that the human central nervous system has a high degree of redundancy on the mircoscale to compensate for the unreliability and noisiness of its neuronal components. One would therefore expect a substantial efficiency gain when using more reliable and versatile non-biological processors.
So, in principle, and utterly in theory, even imposing our primitive lower limits of computational development, assuming there are no major and unexpected changes in quantum manipulation and the laws of physics, it is not unfeasible to create a system with enough power and complexity to create a simulated human brain, and so potentially a human mind. Bear in mind that the proposed computational power of the brain as listed above is well within the means of the sugar-cube sized system proposed by Drexler.
So the first assumption is that even with todays limited understanding, a posthuman civilization could, in all likelihood, have at its disposal the computational wherewithall to replicate one, if not billions, of thinking, sentient brains. But, even with the horsepower to do such a thing, is such a simulation actually feasibly possible?
Mind Over Matter
Bostrom’s theory makes a second assumption: that of substrate independence. Simply put, he assumes that the process of conscious thought and the creation of the physical processes that lead to it are not in any way dependent on the medium in which those process occur. He posits that as long as the process reaches a sufficient and key level of complexity, the emergence of consciousness will inevitably occur, regardless of whether the medium (or substrate) in which the process occurs is carbon-based (as in the neural networks of the human brain) or silicon-based (as in the processors of a sufficiently powerful computer). It is the complexity that is key, not the material. However, he does not take this assumption lightly, and again in the 2003 paper explains:
The argument we shall present does not, however, depend on any very strong version of functionalism or computationalism. For example, we need not assume that the thesis of substrate-independence is necessarily true (either analytically or metaphysically) – just that, in fact, a computer running a suitable program would be conscious. Moreover, we need not assume that in order to create a mind on a computer it would be sufficient to program it in such a way that it behaves like a human in all situations, including passing the Turing test etc. We need only the weaker assumption that it would suffice for the generation of subjective experiences that the computational processes of a human brain are structurally replicated in suitably fine-grained detail, such as on the level of individual synapses. This attenuated version of substrate-independence is quite widely accepted.
Neurotransmitters, nerve growth factors, and other chemicals that are smaller than a synapse clearly play a role in human cognition and learning. The substrate-independence thesis is not that the effects of these chemicals are small or irrelevant, but rather that they affect subjective experience only via their direct or indirect influence on computational activities. For example, if there can be no difference in subjective experience without there also being a difference in synaptic discharges, then the requisite detail of simulation is at the synaptic level (or higher).
So, we have the two key assumptions in place:
The computational power to create conscious, thinking simulations is possible
The creation of consciousness within an artificial system is also possible.
Now we know possibly why a posthuman society would create an Ancestor Simulation and that it is not impossible that they would be able to, we have to look at exactly how likely this is, and what that means for what we perceive as “reality”.
In part 3 we will look at some utterly scary mathematical equations and break our entire existence into three simple and distinct possibilities. Hint: it’s not all good news.
So far in parts one and two of this series we have investigated the parts of Nick Bostrom’s Ancestor Simulation theory that suggest why and how a highly advanced civilization may create a fully-believable simulation of an entire world. Now let’s look at the chances that our world, the universe we experience every day, is in fact nothing more than such a simulation.
Better set some time aside for this, as we’re are going to invoke the darkest of all dark magic – scary maths.
So far we have discussed how it is impossible to determine for certain that a suitably advanced technological society would not have the desire or reason to create a simulation of an entire ancestral civilization (or any civilization for that matter – be it of the creators’ ancestors or a totally made-up civilization). We have also theorized that, even with the limitations of current technological development and the basic laws of physics as we understand them now it is not inconceivable that a system so advanced is possible that it would be able to replicate the human brain and functioning thereof, to the point of consciousness.
We have assumed that the creation of consious awareness in a system is not dependent on the physical structure of the brain or object in which the awareness grows and develops, as consciousness is a function of complexity rather that substrate.
We have also looked at the the idea of the “envatted brain” and concluded that, for all intents and purposes, providing that there is no frame of reference, there is pretty much no way for the simulant to know that he or she is such (the final part of the discussion will discuss in more detail the actual nuts and bolts of everyday life as a simulated being).
Let’s get mathematical
So, with all these assumptions in place, we can now look at the odds. What odds? Well, for fun, let’s look at the odds that human civilization is in fact so advanced that it has created such a simulation, and that the universe we know and love is in fact that very simulation. The idea that we are not in fact the modern humans – that we are in fact the ancestors, and simulated ones to boot.
Now, this is a pretty far-fetched idea, right? That in the “real universe” it is not actually 2008, but some far-distant time (to us) when humans have mastered awesome computing power, perhaps using physics we can’t even comprehend yet (bearing in mind there is a lot of known physics we can’t comprehend now) and that for reasons unknown they have directed themselves to create a full simulation of life in 2008, from individual people to grass, to the sun, to the stars, insects, air, laws of physics and everything else. And that the simulants in there suspect nothing. Well, let’s see how it stacks up.
(Warning – the following will most likely only be fully understood by maths ninjas and people with enormous foreheads)
Bostrom illustrates the basic principle of his theory with some elegant mathematics. He applies it to a posthuman civilization (and uses the term) but in reality this can be seen as applied to any civilization, not necessarily human. Posthuman is just a convenient frame of reference.
He starts with three basic units:
He then adds two extra elements: to represent the number of posthuman civilizations able to run such a simulation as we have discussed (or at least with enough individuals who have the resources and interest to create such simulations), and to represent the average number of Ancestor Simulations run by such a civilization. This gives us:
Which when added in would give us:
We have already discussed that the computing power of a posthuman civilization, in order to create such a simulation, would be immense, therefore is a large value. If you follow the maths to its logical conclusion, by examining (*) it leaves you with three possibilities, one of which must be true:
Now, at this point, Bostrom discusses the Indiffrence Principle. Simply put, a strong Indifference Principle could be used against the outcome in (3) above to reduce the validity of the outcome, Basically, it suggests that by examining your experiences and realities you should be able to determine whether your existence is that of the real world or the simulation, and validate any theory as to which you are in from there. However, because the nature of such a simulation is that it is impossible to tell whether you are simulated or not, it cannot have any effect on the outcome or its validity.
To put it more simply, some would say “But, we know we are in the real world, because we breathe and because physics works as we predict and because I can feel the sun on my face, therefore (3) is invalid and the entire mathematical contruct is in error as we are in the real world, not the simulation.” Sadly, this argument does not hold any water as, if the sun on your face is merely a line of code telling your simulated mind that you are in the sunshine, or if the laws of physics as we know them work just fine because that is the way they are programmed to work, then you have no valid frame of reference and therefore no way to know which you are – real or simulated. In essence, a strong Indifference Principle requires that you know to which set you belong, but in a simulation this is impossible – meaning that it is also impossible to verify (3) as in error or not. He suggests that in place of a strong Indifference Principle, a weak or bland principle shoud be used, and actually validates (3). He explains:
“We can take a further step and conclude that conditional on the truth of (3), one’s credence in the hypothesis that one is in a simulation should be close to unity. More generally, if we knew that a fraction x of all observers with human-type experiences live in simulations, and we don’t have any information that indicate that our own particular experiences are any more or less likely than other human-type experiences to have been implemented in vivo rather than in machina, then our credence that we are in a simulation should equal x:
If betting odds provide some guidance to rational belief, it may also be worth to ponder that if everybody were to place a bet on whether they are in a simulation or not, then if people use the bland principle of indifference, and consequently place their money on being in a simulation if they know that that’s where almost all people are, then almost everyone will win their bets. If they bet on not being in a simulation, then almost everyone will lose. It seems better that the bland indifference principle be heeded.
Further, one can consider a sequence of possible situations in which an increasing fraction of all people live in simulations: 98%, 99%, 99.9%, 99.9999%, and so on. As one approaches the limiting case in which everybody is in a simulation (from which one can deductively infer that one is in a simulation oneself), it is plausible to require that the credence one assigns to being in a simulation gradually approach the limiting case of complete certainty in a matching manner.”
Pick a cup
So, now we have three conlusions, (1), (2) and (3), with the solution above giving unity to (3) – the possibility is that we are within an ancestral simulation of some kind. But let’s look at all three in more detail.
What is proposed by (1) is that the human race, or any other species on our planet, will fail to reach a posthuman level of technological evloution which would allow it to create an ancestral simulation. Whilst it does not specifically say that we will all become extinct before reaching the posthuman stage, Bostrom asserts that there is:
“no justification for thinking that our own species will be especially privileged or protected from future disasters. Conditional on (1), therefore, we must give a high credence to DOOM, the hypothesis that humankind will go extinct before reaching a posthuman level:
One can imagine hypothetical situations were we have such evidence as would trump knowledge of For example, if we discovered that we were about to be hit by a giant meteor, this might suggest that we had been exceptionally unlucky. We could then assign a credence to DOOM larger than our expectation of the fraction of human-level civilizations that fail to reach posthumanity. In the actual case, however, we seem to lack evidence for thinking that we are special in this regard, for better or worse.”
Basically, for (1) to be true, we’re all pretty much fucked.
With (2) the implication is less disastrous, but equally disheartening. For (2) to be true, it suggests that we are not within a simulation, but rather than this being so because of our own failings it is due to there being no desire to create such a simulation. For the number of Ancestor Simulations to be large, it corresponds that the number of creator posthuman civilizations will also be large. For the number of simulations to be very low, or none, the number of posthuman civilizations may still be large, but there would have to be a convergence in that all these civilizations would have to consciously decide not to create such simulations.
This may be for a number of reasons. It is important to note that in all of human history there has been a strong desire to understand our past, and any historian given the resources to recreate an entire civilization – be it the Roman Empire, ancient Greece, World War Two or modern day society – anything – would jump at the chance. For (2) to be correct, it would suggest an inconceivable paradigm shift away from this natural curiosity – to know from where we came and how we ended up where we are – to one of indifference.
It’s not impossible, it should be supposed, that this may happen. Perhaps future posthuman society would have a very strong moral and ethical code that would see the creation of a simulation as causing unneccesary suffering to those within it. Such a civilization would be well aware that the entities within the simulation would be thinking, conscious beings, despite the fact they exist only in a computer program. And creating a simulation without (simulated) pain, disease and suffering would render the simulation useless as the entire point of the excercise is to recreate true past events, not to create a shiny, peaceful utopia that never existed. Such a rainbow-colored program would serve no purpose and would offer no valid data.
Or, perhaps more simply, the posthuman society would be so far removed from us now that they would derive no benefit or value from such a simulation. Or maybe the things that bring us pleasure now – challenge, a desire for knowledge and an understanding of our past – would mean little to a future human society. It is possible that we cannot even comprehend the priorities of such a highly-evloved society.
Why would this be disheartening? It would be so because although it means that the human race survives long into the future and evloves beyond our wildest dreams, what happens here and now will be forgotten and never thought of – or be of any value – again. As a society we are a tribe of story tellers. We live through our history – stories of bravery, sacrifice, discovery, endeavor. As an example, consider survivors of World War One. There remain on this earth very few; most are long dead. But every year we comemmorate those who perished, and give thanks to those who did not. We celebrate the ultimate sacrifices and give thanks for the changes that resulted. Imagine if this was not the case – if such sacrifices were never even acknowledged and no-one now knew anything about it. We are our history, we live it and breathe it, and without it we are very little. And to think that, no matter how much you strive to live on in memory once you are gone, you will ultimately be forgotten is a sad thought.
(3) is by far the most intriguing (and kinda scary) solution, and for this I will let Bostrom explain, as he does so much better than me:
“The possibility expressed by alternative (3) is the conceptually most intriguing one. If we are living in a simulation, then the cosmos that we are observing is just a tiny piece of the totality of physical existence. The physics in the universe where the computer is situated that is running the simulation may or may not resemble the physics of the world that we observe. While the world we see is in some sense “real”, it is not located at the fundamental level of reality.
It may be possible for simulated civilizations to become posthuman. They may then run their own Ancestor Simulations on powerful computers they build in their simulated universe. Such computers would be “virtual machines”, a familiar concept in computer science. (Java script web-applets, for instance, run on a virtual machine – a simulated computer – inside your desktop.) Virtual machines can be stacked: it’s possible to simulate a machine simulating another machine, and so on, in arbitrarily many steps of iteration. If we do go on to create our own ancestor-simulations, this would be strong evidence against (1) and (2), and we would therefore have to conclude that we live in a simulation. Moreover, we would have to suspect that the posthumans running our simulation are themselves simulated beings; and their creators, in turn, may also be simulated beings.
Reality may thus contain many levels. Even if it is necessary for the hierarchy to bottom out at some stage – the metaphysical status of this claim is somewhat obscure – there may be room for a large number of levels of reality, and the number could be increasing over time. (One consideration that counts against the multi-level hypothesis is that the computational cost for the basement-level simulators would be very great. Simulating even a single posthuman civilization might be prohibitively expensive. If so, then we should expect our simulation to be terminated when we are about to become posthuman.)
Although all the elements of such a system can be naturalistic, even physical, it is possible to draw some loose analogies with religious conceptions of the world. In some ways, the posthumans running a simulation are like gods in relation to the people inhabiting the simulation: the posthumans created the world we see; they are of superior intelligence; they are “omnipotent” in the sense that they can interfere in the workings of our world even in ways that violate its physical laws; and they are “omniscient” in the sense that they can monitor everything that happens. However, all the demigods except those at the fundamental level of reality are subject to sanctions by the more powerful gods living at lower levels.
Further rumination on these themes could climax in a naturalistic theogony that would study the structure of this hierarchy, and the constraints imposed on its inhabitants by the possibility that their actions on their own level may affect the treatment they receive from dwellers of deeper levels. For example, if nobody can be sure that they are at the basement-level, then everybody would have to consider the possibility that their actions will be rewarded or punished, based perhaps on moral criteria, by their simulators. An afterlife would be a real possibility. Because of this fundamental uncertainty, even the basement civilization may have a reason to behave ethically. The fact that it has such a reason for moral behavior would of course add to everybody else’s reason for behaving morally, and so on, in truly virtuous circle. One might get a kind of universal ethical imperative, which it would be in everybody’s self-interest to obey, as it were “from nowhere”.
In addition to ancestor-simulations, one may also consider the possibility of more selective simulations that include only a small group of humans or a single individual. The rest of humanity would then be zombies or “shadow-people” – humans simulated only at a level sufficient for the fully simulated people not to notice anything suspicious. It is not clear how much cheaper shadow-people would be to simulate than real people. It is not even obvious that it is possible for an entity to behave indistinguishably from a real human and yet lack conscious experience. Even if there are such selective simulations, you should not think that you are in one of them unless you think they are much more numerous than complete simulations. There would have to be about 100 billion times as many “me-simulations” (simulations of the life of only a single mind) as there are ancestor-simulations in order for most simulated persons to be in me-simulations.
There is also the possibility of simulators abridging certain parts of the mental lives of simulated beings and giving them false memories of the sort of experiences that they would typically have had during the omitted interval. If so, one can consider the following (farfetched) solution to the problem of evil: that there is no suffering in the world and all memories of suffering are illusions. Of course, this hypothesis can be seriously entertained only at those times when you are not currently suffering.
Supposing we live in a simulation, what are the implications for us humans? The foregoing remarks notwithstanding, the implications are not all that radical. Our best guide to how our posthuman creators have chosen to set up our world is the standard empirical study of the universe we see. The revisions to most parts of our belief networks would be rather slight and subtle – in proportion to our lack of confidence in our ability to understand the ways of posthumans. Properly understood, therefore, the truth of (3) should have no tendency to make us “go crazy” or to prevent us from going about our business and making plans and predictions for tomorrow. The chief empirical importance of (3) at the current time seems to lie in its role in the tripartite conclusion established above. We may hope that (3) is true since that would decrease the probability of (1), although if computational constraints make it likely that simulators would terminate a simulation before it reaches a posthuman level, then out best hope would be that (2) is true.
If we learn more about posthuman motivations and resource constraints, maybe as a result of developing towards becoming posthumans ourselves, then the hypothesis that we are simulated will come to have a much richer set of empirical implications.”
So, there you have it. In a nutshell, we either die out, are forgotten utterly, or don’t actually exist. And the scary maths suggest that of all these three, (3) is statistically the most likely.
In our final look at Ancestor Simulations, we’ll briefly touch on Bostrom’s view of what the greater implcations are for “life in a vat”, and what it would be like were we in one.
So far, we have examined the workings behind Nick Bostrom’s Ancestor Simulation hypothesis, looked at the how’s and the why’s of such an endeavor. Part one, part two and part three (hopefully) illustrate how, probabilistically, we are more likely to be in such a simulation than not. Now, in part four, we will briefly look at what it means to be simulated, how it would work, and if we would ever have any way to know for sure.
It is important to realise that what Bostrom has put forward is not proof or otherwise that pits reality against simulation in relation to our own perceived reality. It is merely an argument of probability, which is intended to lead us towards discussion of our existence and the ntaure of that reality:
“I believe that the simulation argument is sound. The argument shows only that at least one of three possibilities obtains, but it does not tell us which one(s). One can thus accept the simulation argument and reject the simulation hypothesis (i.e. that we are in a simulation).”
“Thus, the simulation argument is not best thought of as a skeptical argument that would have us be more agnostic, but rather as an argument that would have us increase our credence in one particular disjunction (and decrease our credence in its negation). It aims to tell us something about the world rather than to advise us that we know less about the world than we thought we did.”
But, regardless of how the argument is actually interpreted or used, it most clearly puts forward questions that are universal, regardless of the specific ins and outs of “is it possible to do?” or “why would it be done?”
Let’s assume for a moment that the statistics are balanced towards option (3) – that we are actually living in an Ancestor Simulation. What does that mean? Would there be any way for us to prove it? Would we ever become aware of it?
In short, with only one major exception, no.
We shall assume that an originating civilization has created the simulation in which we live, and assume that they are technologically able to simulate not just one human mind, but all the human minds living at this point in time, along with the universe that we experience around us. We won’t worry about their motivations; just assume that it is so. What questions are raised?
The easiest thing to do is use a comparable to give yourself a basic frame of reference. Turn on a videogame console and start up a game. Let’s say, for the sake of illustration, that we are playing Halo. Now pause the game and imagine that YOU are the progenitor civilization, and the game is the simulation that you have created. Imagine for a second that as well as the game world, the NPC’s within the game and the sounds and visuals, you have been able to program the protagonist – Master Chief – will a fully-fledged mind, to the extent that consciousness is present (or at least, to the extent that the Chief perceives himself to be conscious). We will call upon this frame of reference to help illustrate some of the questions we may come across.
One popular question often posed is that, if we are all in a simulation running on some fantastic super-computer, wouldn’t there be times when things go a bit wonky and something goes a bit wrong? A universal “blue screen of death”? And if so, surely we would identify these “glitches” and be able to use them as signs pointing to our artificiality?
Well, yes and no.
It is highly likely that any complex system, whether the human brain, your laptop or some vast stellar super computer of a progenitor would, from time to time, encounter calculation errors resulting in flaws and glitches. if we assume that the simulation in which we find ourselves is simulating every living organism on our planet, as well as the planet itself, the observable universe, and all the interactions and physics therein, it is safe to assume that occasionally, such massive computation will fall flat on its ass, or would create strange artifacts due to sloppy programming or omissions.
Glitches or bugs in a videogame can include such things as clipping (objects passing through each other due to incorrect physics routines or bounding box errors), missing objects, objects lacking textures (appearing “blank”), strange AI behaviours, odd audio effects, and many more.
In our souped-up game of Halo, a glitch or bug might mean that the Chief sees a tree hovering a few feet off the ground (which there famously is on the level Assault On The Control Room), or a vehicle thrashing about seemingly of its own accord as the physics engine tries to reconcile its position to a rest-state when another object is in the way. Perhaps he sees an enemy Elite standing there ignoring him, seemingly unable to see the Chief or carrying out strange repetitive actions, as if stuck in a loop.
Now, as we have injected the Chief (in this special release of the game) with human intelligence, it is natural to assume that he would be a little freaked out by something like a hovering tree or a jiggling Bansee vehicle. If you or I dropped a weapon to the ground only to see it spin wildly because it was against a wall and because the program could not reconcile the fact that the final destination of the dropped weapon is beyond or within that wall (because the physics engine had not correctly “bounced” the weapon off of the wall), we would certainly be a little shocked. We would perhaps question our own sanity, or start to think perhaps a poltergeist or some other malevolent force was at work. A scientist might accept the strange behavior as not particularly mystical, and decide to examine it fully, to find out what is causing the phenomenon.
But there is one thing to remember: it is highly unlikely that the person running the simulation wants to send the entities within it on a quest to expose it. After all, if I am running a simulation to evaluate human history, the last thing I need is to make the simulation obvious to those within it, as this would break away from the original history upon which the simulation is based, and render the data useless.
So, it is safe to assume that yes, in an Ancestor Simulation, the creators would be just as guilty as today’s software engineers – sometimes it is impossible to test for everything, some things get left out due to time constraints, and oddities can ensue. So, we just need to look hard and find the glitches, right? Wrong. We never will, because such activity is undesireable to the creator. Therefore, tools will be available to rectify glitches in a way we would not perceive.
It is a problem very easily solved – when a glitch of some sort occurs, simply pause the program, fix the bug, and rewind the program to a few seconds before the bug occurred. Simple. If I am playing a normal game of Halo and I somehow manage to get the Master Chief outside the permitted map area with no way to get back, I simply pause the game and go back to the last saved checkpoint, carrying on as if nothing had happened. In our simulation, although we would experience the glitch, once it was fixed and returned to normal, we would be “rewound a few minutes” and our brain-states would return to the way they were at exactly the point from which play resumed – leaving no trace of memory of the glitched event or rewind. For all we know, we could be finding glitches every single day, and have no way to know. And absolutely no way to prove that it happened.
In The Matrix, Neo experiences déjà vu, and sees a black cat pass a doorway twice. He innocently points this out, and is advised that this means that something has been changed in the Matrix-simulation and this is a glitch that occurred as a result. However, in reality (no pun intended) this would not occur beause once the glitch was rectified or the change made, he would be returned to just prior to the glitch occurring, have no memory of it and therefore not be able to bring it to the attention of his allies.
Therefore, the presence or perception of bugs and glitches cannot be used to prove or disprove the possibility that our reality is simulated.
It’s all too much!
Many people suggest that infinity itself is the sole agent that can determine the “realness” of reality. That, despite the creator civilization having super-duper awesome computing at their disposal, there is no way they could create an infinite universe – that being the universe we observe both visually and in mathematics. This fact surely makes such a simulation untenable?
Well, no, not really.
The fact that mathematics can create infinity does not mean anything, in terms of computing power. Instrinsically, just because an equation on a blackboard suggests that the universe is infinite does not mean that it requires such a universe to exist. And the fact that we can make visual observations that suggest an infinite universe equally does not mean that the infinite universe has to actually exist for us to see it.
Simply put, it is a valid point that it would be prohibitive to run a simulation that requires the creation of infinity. However, it would also be incredibly pointless to actually create such an infinity all the time when, for the most part, observation of this infinity is almost never taking place.
In game design, this is called LOD or Level Of Detail. In our pimped game of Halo, the Chief can be standing an an enormous valley, snow falling, wind whipping at his armor, and he can look up and see a starry sky. In that sky, he will see galaxies far away, shimmering amidst the stars. To him, that is the observable universe, many millions or even billions of light years away. He could take out a ridiculously powerful telescope, and perhaps bring it to bear on a distant galaxy, and marvel at the hundreds of millions of stars within that galaxy, and how he is now able to see many more galaxies even further away.
But you are the programmer for his reality – a reality he accepts and perceives as totally real – and you really haven’t got a few spare millennia (or the memory in your upgraded super-powerful Xbox) to create all these trillions of stars and galaxies. So instead, you bring LOD to bear. Around the valley you create a skybox -literally a box around the valley he perceives upon which lives a simple texture map of the night sky. Perhaps it is animated to show clouds, shooting stars and movement of the celestial scenery. It does not need to be very high-resolution, because it is supposed to be a very long way away from the Chief, and he is observing it with the naked eye. However, does it follow that when he whips his telescope out, he will see a clunky low-resolution texture map of the night sky? No. When he looks through the telescope, then he sees a chunk of the outside universe with stars and galaxies in higher detail – a different image to the one he was seeing just a moment ago. But, this could again be a simple two-dimensional animated image, as there is no need to use complex modelling at these perceived distances. In effect, there is no limit to how far out into space the Chief looks, as no matter what he uses, he always gets the same thing – a very simple but detailed image that he beleives is the dark, mysterious depths of space, many many light years away. In reality, such an image would probably require less processing power than his own armor, in terms of system resources.
So, in effect, what our simulation creators could do, with very little impact on their system resources, is effectively show us what we need to see, on demand, instead of generating and rendering the whole universe.
The same can be said for the other direction – the quantum world. In the same way, it is not neccessary for the simulation to render down to the atomic or sub-atomic scale. The simulation only needs to constantly render to the naked eye level of resolution. Greater resoltions can be provided on demand, locally to the observer, when magnification equipment is used. In the Ancestor Simulation, it is more likely that it would not be an image, per se, but rather code that convinces the observer that they are seeing what they are.
So, level of detail, or the existence of infinity cannot be used to prove or disprove the possibility that our reality is simulated.
It’s all too much! Again!
Another argument along the lines of the resource management discussion above is that although it is conceivable that the creation of an entire universe – at whatever level of detail – by some supercomputer is possible, surely running the program real time would just be too much. There would be so much to process that it would never get off the ground.
Well, whilst that suggests a certain arrogance about just exactly what a future technological civilisation may or may not be capable of building, it has a fatal flaw.
Who said anything about real-time?
When Pixar creates on of its fantastic CGI animated films, it does not build the whole thing on the shelf, characters, actions and all, and then simply render it to a video recorder. Each frame of film, 24 for each second, is rendered individually. The movements and actions are planned and built in, and the film comes together, frame by frame, on huge render farms that are made up of many, many servers. Each server might render a few frames in an hour. Back in the day, it could take a whole day to render a single frame. For an hour and a half long film, that’s 129,600 frames, renderd one by one. Nowadays of course the process is much faster (even though the amount of stuff being rendered by the computer is much greater, much more complex and contains more elements).
In the same vein, it is possible to imagine that the race creating the simulation have a bank of “servers” that can “render” the simulated reality. Let’s, for the sake of argument, assume that they render this simulation in frames, like an animated movie. Let’s also assume that their “frames” are actually units of time. For the sake of argument, we will assume that they render the simulated “reality” in frames that are in fact a jiffy long. A jiffy is the rather endearing name for what physicists believe is the smallest feasible and measurable unit of time – according to Wikipedia:
“In astrophysics and quantum physics a jiffy is, as defined by Edward R. Harrison, the time it takes for light to travel one fermi (the size of a nucleon). One fermi is 10−15 m, so a jiffy is about 3 × 10−24 seconds.”
Now, if the creator race have computers that are so powerful they can render a simulated reality at the jiffy level, real-time, then great. Yay them. That’s really powerful tech, they have teh smartz and everyone loves everyone.
But wait. That’s a hell of an assumption. For all we know, they can’t render real-time. We discussed in a previous blog that the instincts that drive man to enquire about his history and his surroundings are inherent in human nature – and will never be forgotten. So it is silly to assume that scientists, eager to simulate a reality for whatever reason, would figure out how to do it and then decide to wait for another few thousand years just beacuse it had to be real-time. Of course they wouldn’t. And they wouldn’t because they would know full well that the render speed of the simulation is irrelevant to the entities living within the simulation.
What do I mean? Simply put, if we were simulated, then we would only be “aware” at the same level of quantisation as the simulation. Our perceptions and thought processes would be rendered and be active only at the same rate as the rendering itself. So I would experience a jiffy of time, then nothing, then the next jiffy, and so on (of course, I would not actually “experience” a jiffy but you know what I mean). I would no more sense the pauses between jiffies than you perceive the spaces between frames in a CGI animated movie, or than my super-conscious Master Chief would be aware that I had paused the Halo game to go get a coffee. Whether each jiffy was rendered real-time, or a thousand million years apart, to a simulated entity reality would simply proceed at normal speed.
This means that being able to “render” a simulation real-time is not a pre-requisite for the creation of a simulated reailty.
The fact that it may require just too much computing power to “render” a simulation in real-time cannot be used to prove or disprove the possibility that our reality is simulated.
I think, therefore…I might be?
Consciousness – the sense of self, the “I” in “me” – is an interesting subject. No-one is able to say for sure what it is, or why it is. It could be a side effect of the complexity of the human brain and it’s complex workings. It could be a matter of the soul – an entity that lives within us, and merely inhabits us on our journey of life. Who knows? But in terms of this discussion, does it totally negate the possibility of reality being simulated?
If consciousness is merely a by-product of a complex system then, as we have already stated in our breakdown of the underlying requirements for a simulation, there is nothing available to us in our current uinderstanding of physics, biology or metaphysics to suggest that such consciousness-creating complexity is dependent on substrate – i.e. it is not a matter of what the system is made of that determines the generation of consious thought. There is no reason to suspect that consciousness would not occur in a suitably complex system made from electronic components, or even software components. Without the knowledge of such a limitation, it is untenable to claim that substrate is critical, and therefore any argument that a virtual brain would not create conscious thought is moot.
It is also important to remember that there is also nothing in our current knowledge to prevent us assuming that consiousness is merely a manufactured illusion, or that in a simulation consiousness could not be programmed, rather than actually existing. We do not have the technological capability to say if it possible to simulate consciousness, let alone create it in genuinely by way of a suitably complex system.
On the other hand, it could be assumed that consciousness is an entity – like a soul – that is seperate from our bodies and therefore almost like a beneficial parasite or symbiotic organism within us. Interestingly, this idea both proves and disproves the simulation argument at the same time. Bear in mind here that I am using the word “soul” outside any religious context and with no inherent confirmation of any religious connotations – it is merely a word I choose to use to denote the consciousness within us, because I am getting frustrated typing the word “consciousness” so much!
If our preceived universe is actually real, and not a simulation, and if our “self” is actually a separate entity, then in effect we are still simulated – to a certain degree. Our physical selves would merely be avatars, or vehicles, for such an entity. Meaning that the “me” I perceive as “me” is, in fact, not me! Although this would not be a simulation in the same vein as a full Ancestor Simulation, it woud still, nontheless, reduce our existence to something other than we perceive.
Of course, the other alternative is that the “soul” may in fact be a “gamer” – somebody experiencing a fully-simulated universe through direct injection into that simulation. It may be that without the soul or the “conscious entity” we are merely virtual avatars, motionless and without direction, until the “player” jacks into the simulation and takes control.
This, of course, raises a whole new question – if the simulation is in fact interactive and has “players” contolling us, does that mean there is a “player” for each human? Not neccesarily. There may be a limited number of “players”, and the rest of humanity maybe be NPC’s – non-player characters. Dumb bots, if you will. For all you know, you may be the only actual player-controlled character in the whole world, and the rest of us simple drones (albeit very intelligent and convincing drones). There is no way to tell.
As a little aside, Jim Elvidge, author of The Universe – Solved, leans more towards this train of thinking. He expands on the simulation hypothesis much like Nick Bostrom, but favors more the idea that physical entities are “plugged into” and “playing” or experiencing the simulation directly at some level (whereas Bostrom favors the “everything is pure simulation” side of the coin). Both are very compelling and interesting angles, and offer different reasons for such simulations to exist. Ideally, both should be studied alongside each other.
This also creates the ONLY way for us to find out whether we are simulated or not. If numbers of the human race are actually avatars controlled by flesh and blood beings from “out there”, then it would be within their power to tell us our true nature. Why they would do so is another question. And, judging by the typical postings on abovetopsecret.com, they would most likely not be believed anyway!
So, assuming we could prove the existence of a “soul”, or even if we never do, does the concept put a spanner in the works as far as suggesting we are simulated? I think you know the answer by now:
The existence and/or concept of consciousness and/or a “soul” (in any sense) cannot be used to prove or disprove the possibility that our reality is simulated.
I prove that I cannot prove what I prove.
Some suggest that if we are in a simulation, this simple fact disproves the simulation theory altogether.
Basically put, Bostrom’s argument is based on the idea that a suitably tecnologically advanced race would have the capability of creating an Ancestor Simulation. This idea is based on our current knowledge and understanding of physics and technology, and is dependent on us being able to predict what may be possible in the future.
But, it is argued, if we are simulated, we have no way to know that our current understanding of physics and technology is real – that is to say, for all we know, the laws of physics and quantum physics as we know them, and in fact all known laws governing the universe, may bear no relation at all to the “real” laws in the “real” world where the simulation-creator exists. For example, in our super-duper Halo game, I could set the physics engine to make magnets where aligned poles attract rather than repel. Or I could make gravity a strong repellent force rather than a weak attractant force. The Chief, inhabiting what he perceives to be his reality, would have no way to know that in my “real” reality, these laws are not the case, and would assume these as universal and correct laws. Therefore, if we cannot say with 100% certainty that our predictions are possible, we cannot say with 100% certainty that the simulation is someting that the “real world” inhabitants are able to create with their knowledge. Therefore, this suggests that the simulation is either not possible, or gives extra weight to the possibility that we are living in the reality that cannot run a simulation and are therefore real, not simulated.
Hell of a paradox, that one. I think I broke my brain.
But, in fact, it does not stop our reality being simulated at all. The counter reply is such:
- If we do live in a simulation, regardless of whether our understanding of “capability” is correct or not, it proves that a simulation is possible and therefore given the statistical probability of there being more simulations that “real” realities, we are most likely to be simulated, or
- If we are NOT in a simulation then it is more likely that our knowledge and assumptions about future technological capabilities are correct and based on “real” laws of physics – meaning that it we are more likely correct in our assumption that we will develop such a simulation at some point, Again, statistically, if we will one day have such a capability and will more likely have more than one simulation running, the likelihood of there being a greater number of simulated realities than our “real” reality is high and therefore means that in all probability we are more likely to be simulated and not real.
Take a deep breath :)
You know what’s coming…
Being simulated and it’s implications on our understanding of universal laws and technological potential cannot be used to prove or disprove the possibility that our reality is simulated.
In conclusion, what do we have? Well, as Bostrom himself points out, no proof of any kind that our reality is simulated or not. And we probably never will, unless Bostrom has taken the wrong tack and Elvidge has hit the nail on the head with the avatar idea, and we can actually be told. Rather, what we have is a collection of interesting points that compliment the statistical probablility that, in all likelihood, given the assumption that a race will reach the level of technology to create such a simulation, and run many simulations concurrently, it is more likley that we inhabit one of many Ancestor Simulations as opposed to inhabiting a single, “real” reality. Even if the creators run only two simulations, that means that we only have a one in three chance of not being simulated. And then factor in the possibility that their simulated beings may themselves create and run a simulation, and then their simulation may do the same (assuming the creators of each simulation permit it) ad infinitum (although with a lower level of detail each time), the odds of us being the original progenitor race becomes less and less. Indeed, because of this, the simple act of creating a simulation in no way acts as proof that the creators are the “originals”. It can make you dizzy.
I hope that you have enjoyed this article, and that it has opened your eyes to a whole different way of thinking. There is probably no way we will ever know one way or the other whether we are simulated or not. That we exist is not in question – “we think, therefore we am”! But we can gain insight into reality and our perceptions. Not only does the concept ask interesting questions of the nature of reality, and our perceptions of it, it forces us to look into theology as well. In pretty much every religion and faith there is a creator myth. Imagine for one minute that we create an Ancestor Simulation. Think about how we would appear to the simulated entities. We would have mystical powers to create and destroy life as we saw fit. We would control their entire universe. We could appear or disappear within the simulation at will. We could make bushes burn, make seas part, speak from the heavens, attribute magical powers to a chosen few individuals. We would, to the inhabitants and for all intents and purposes, be gods. This is interesting because the Ancestor Simulation hypothesis in of itself does not remove any theistic beliefs – in fact, it lends the idea of a creator God even more weight. If we do live in a simulation, and could prove it, it would, in fact, be irrefutable proof of the existence of God. The real kicker would be to find out that God was, in fact, just another simulation himself. If there is one significant question that stems from all this, it is not “Is God an astronaut?”, it is:
“Is God a computer nerd?”
Foxx, August 2008