The Virtual and the Real

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The Virtual and the Real

David J. Chalmers

How real is virtual reality? The most common view is that virtual reality is a sort of fictional or illusory reality, and that what goes in in virtual reality is not truly real. In Neuromancer, William Gibson famously said that cyberspace (meaning virtual reality) is a “consensual hallucination”. It is common for people discussing virtual worlds to contrast virtual objects with real objects, as if virtual objects are not truly real.

I will defend the opposite view: virtual reality is a sort of genuine reality, virtual objects are real objects, and what goes on in virtual reality is truly real.

We can get at the issue via a number of questions. (1) Are virtual objects, such as the avatars and tools found in a typical virtual world, real or fictional? (2) Do virtual events, such as a trek through a virtual world, really take place? (3) When we perceive virtual worlds by having immersive experiences of a world surrounding us, are our experiences illusory? (4) Are experiences in a virtual world as valuable as experiences in a nonvirtual world?

Here we can distinguish two broad packages of views. A package that we can call virtual realism (loosely inspired by Michael Heim’s 1998 book of the same name) holds:1 2

• (1) Virtual objects really exist.

• (2) Events in virtual reality really take place.

• (3) Experiences in virtual reality are non-illusory.

• (4) Virtual experiences are as valuable as non-virtual experiences.

A package that we can call virtual irrealism holds:

• (1) Virtual objects do not really exist.

• (2) Events in virtual reality do not really take place.

• (3) Experiences in virtual reality are illusory.

• (4) Virtual experiences are less valuable than non-virtual experiences.

The four theses in each package are separable from the others, and it is possible to hold just one or two of the theses in each package. But the theses in each package go especially naturally together. Each thesis needs clarification, which I will give in what follows.

I have explored the philosophical status of virtual reality once before, in my 2003 article “The Matrix as Metaphysics”. That article focuses on a perfect and permanent virtual reality such as the one depicted in the movie The Matrix. In that article (which I will not presuppose any knowledge of here), I argued that if we are in a Matrix, most of our ordinary beliefs (e.g. that there are tables) are true: if we discovered that we are in a Matrix, instead of saying that there are no tables, we should say instead that tables are digital (or computational) objects made of bits. In effect, I answered questions (1)-(4) by saying that at least in the case of a permanent and perfect virtual reality:

• (1) Virtual objects really exist and are digital objects;

• (2) Events in virtual worlds are largely digital events that really take place;

• (3) Experiences in virtual reality involve non-illusory perception of a digital world;

• (4) Virtual experiences of a digital world can be about as valuable as non-virtual experiences of a non-digital world.

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We might call the combination of (1) and (2) virtual digitalism. In this article, I will in effect extend the digitalist view that I have defended for permanent and perfect virtual reality to give the same answers (1)-(4) even for the temporary and imperfect virtual realities that are possible with current VR technology.

• 1 Definitions

First, what is virtual reality? In general, the notion of “virtual X” is ambiguous between two readings. On a traditional reading, “virtual X” means something like “as if X but not X” (consider a virtual tie in an opinion poll, which is not exactly a tie, but functions as if it were a tie). On that reading, virtual reality would be an as-if reality that is not reality, and virtual realism would be ruled out by definition. On a more recent and now more common meaning, “virtual X” means something like “a computer-based version of X” (consider a virtual library, which is a computerbased version of a library). That reading is neutral on whether virtual X’s are X’s, and the answer may vary case by case. For example, it is plausible that a virtual kitten in this sense is not a kitten, but a virtual library in this sense is a library. Understanding the term “virtual reality” this way at least leaves it open that virtual reality is a form of reality.3

There is no universally accepted definition of virtual reality, and the concept exhibits some vagueness and flexibility. Still there is a common core to most uses and definitions of the term.4 Capturing this core, I will say that a virtual reality environment is an immersive, interactive, computer-generated environment. In effect, being computer-generated makes these environments virtual (as on the second definition above), and being immersive and interactive makes our experience of them at least akin to ordinary reality. The three key notions of immersion, interaction, and computer-generation can be explained as follows.

Immersion: An immersive environment is one that generates perceptual experience of the environment from a perspective within it, giving the user the sense of “presence”: that is, the sense of really being present at that perspective.5 Typically this involves inputs that yield a visual experience as of a three-dimensional environment, perhaps along with auditory and other sensory elements. In the present day, a paradigm of immersive VR technology involves a headset with a stereoscopic display. In the future one can imagine that glasses, contact lenses, or implants could accomplish the same thing.

Interaction: An environment is interactive when actions by the user make a significant difference to what happens in the environment. In current VR, this interaction takes place through the use of input devices such as head- and body-tracking tools, handheld controllers, or even a computer keyboard.

Computer generation: An environment is computer-generated when it is grounded in a computational process such as a computer simulation, which generates the inputs that are processed by the user’s sensory organs. In current VR this computation usually takes place either in a fixed computer connected to a headset display or in a mobile computer (such as a smartphone) embedded in a headset using its own display.

We can also say that virtual reality technology is technology that sustains virtual reality environments. “Virtual reality” as a count noun is roughly synonymous with “virtual reality environment”, while as a mass noun it covers both virtual reality environments and virtual reality technology.

The term “virtual reality” is often used in looser ways than this— sometimes so loose as to include almost any nonstandard means of generating experiences as of an external environment. To allow distinctions between grades of VR, we might say that “VR proper” is virtual reality that satisfies all three conditions above. We can then capture more inclusive notions of virtual reality by removing these conditions.

We can start by removing the three conditions one at a time. Nonimmersive VR includes computer-generated interactive environments displayed on desktop computer or television screens, as with many familiar videogames. Noninteractive VR includes passive immersive simulations such as computer-generated movies presented on a VR headset. Non-computer-generated VR includes immersive and interactive camera-generated environments, such as the remote-controlled robotic VR sometimes used in medicine. The label of VR is also sometimes applied to environments satisfying just one of the three conditions: immersiveness (e.g. movies filmed with 360-degree cameras and displayed on a headset), interactiveness (e.g. remote control of a robot using a desktop display of its perspective), or computer generation (e.g. a computer-generated movie displayed on a desktop). The label is not typically applied to environments that satisfy none of the three conditions, such as ordinary (two-dimensional, passive, camera-based) movies and television shows. That said, it is interesting to note that the term “la realite virtuelle” was first introduced by Antonin Artaud (1938) to apply to the theatre, which is typically noninteractive and environment, while “presence” is used for the corresponding properties of a user’s subjective experience.

non-computer-generated and arguably nonimmersive.

There are also intermediate cases. So-called mixed reality involves immersive and interactive environments that are partly physical and partly computer-generated. The paradigm case of mixed reality is augmented reality where virtual objects are added to an ordinary physical environment. Mixed reality is typically contrasted with VR, but it can also be considered as VR in an extended sense. Ordinary un-augmented physical environments are also immersive and interactive, but they are not usually considered to be VR, except perhaps by people who think that the external world is computer-generated or that it is a mind-generated construction.

What is a virtual world? I take a virtual world to be an interactive computer-generated environment, of the sort that we (seem to) inhabit when using virtual reality. On common usage, nonimmersive desktop videogames such as World of Warcraft which are not strictly virtual realities nevertheless involve virtual worlds. This usage suggests that there is no immersiveness condition on virtual worlds. We will see that when it comes to ontological issues about virtual worlds, nonimmersive and immersive VR raise very similar issues, so it makes sense to drop the immersiveness condition in this domain for a broader analysis.

What is a virtual object? I take these to be the objects that are contained in virtual worlds and that we (seem to) perceive and interact with when using virtual reality. Paradigmatic virtual objects include avatars (virtual bodies), virtual buildings, virtual weapons, and virtual treasures.

These definition are neutral on whether virtual worlds and virtual objects are real or unreal. I take it that realists and irrealists can both agree that virtual worlds are computer-generated, that we seem to inhabit them, and that virtual worlds contain virtual objects that we seem to interact with. For example, whether the world of Azeroth in World of Warcraft is a digital world or a fictional world, it is computer-generated, we seem to interact with it, and it contains virtual objects either way.

• 2 Virtual Fictionalism

The large majority of philosophers who have written about virtual worlds are virtual irrealists. More specifically, they hold that virtual worlds are fictional worlds. We might call this view virtualfictionalism.5 On this view, virtual worlds have a status akin to Tolkein’s Middle Earth, and virtual objects have a status akin to that Gandalf or the One Ring: they do not exist in reality, but only in fiction. Likewise, the things that are supposed to happen to them do not happen in reality, but only in fiction.

Virtual fictionalism can naturally be associated with the following cluster of views on our original question (though certainly not all virtual fictionalists need endorse all of these theses):

• (1) Virtual objects are fictional objects.

• (2) Virtual events take place only in fictional worlds.

• (3) Experiences in virtual reality involve illusory perception of a fictional world.

• (4) Virtual experiences have the limited sort of value that engagement with fiction has.

Many of these theorists have focused on the virtual worlds present in videogames, for which fictionalism is an especially natural thesis. For example, there are many videogames based on Tolkein’s works and set in Middle Earth. If the Middle Earth of the books is fictional, so presumably is the Middle Earth of the games. There are also videogames set in historical periods such as the Second World War, while depicting events (such as the assassination of Hitler) that did not really take place then. A book or movie depicting these events would be fictional, and the same goes for a videogame.

It is misleading to take videogames as one’s prime model for virtual reality, however. There is of course a close connection between any role-playing game and an associated fiction, but this connection holds whether the game is virtual or non-virtual. If a human in physical reality plays the role of Gandalf casting a spell in Middle Earth, the event of Gandalf casting a spell is fictional, but the underlying bodies and movements are real. Likewise, if an avatar in virtual reality plays the role of Gollum stealing the ring, the event of Gollum stealing the ring is fictional, but this is consistent with the underlying avatars and movements within the virtual realm being real.

Furthermore, videogames are just one among many possible uses of virtual reality technology. At the moment, videogame worlds are the most popular virtual worlds, but this is unlikely to stay the case indefinitely. There are already many virtual worlds that are not especially game-like in character. When a virtual world is used for non-play purposes such as socializing, gathering 5Varieties of virtual fictionalism are expounded by Juul 2005, Tavinor 2009, Bateman 2011, Velleman 2011, and Meskin and Robson 2012. To be fair, many of these theorists are making claims about videogame worlds rather than about virtual worlds more generally. Some of these fictionalists also distinguish special respects in which virtual realities are real: for example, they involve real rules (Juul) or agents who literally perform fictional actions with fictional bodies (Velleman). Aarseth (2007) denies that virtual worlds are fictional while nevertheless holding that they are not real: they have the same sort of status as dream worlds and thought experiments, which he also understands as not fictional.

information, or communicating with colleagues, it is much harder to discern fictionality in the virtual world.

The well-known virtual world Second Life, for example, is generally characterized as a platform rather than a game. There is no special objective in the world of Second Life. Users can use the world for activities and interactions of all sorts. Suppose I enter the virtual environment of Second Life in order to have a conversation with a friend. In what sense is what goes on fictional? I am really having a conversation with my friend: this is not fictional at all. Presumably if there is a fiction here, it involves our avatars. For example, perhaps the virtual world depicts us as having certain bodies which we do not really have, and depicts our bodies as being a few meters apart when in fact we are thousands of miles apart.

I think this is the wrong way to think about Second Life and other virtual worlds. The right way is this. The virtual world of Second Life involves virtual bodies (avatars) in virtual space. Virtual bodies are distinct from physical bodies, and virtual space is distinct from physical space. We really have these virtual bodies, as well as having physical bodies. There is nothing fictional about this. These virtual bodies really inhabit virtual space, where they are really a few (virtual) meters apart. There is nothing fictional about this. If I pick up a virtual coin in Second Life, I really use my virtual body to take possession of a virtual coin. There is nothing fictional about this.

I will defend this picture in what follows.

• 3 Virtual Objects

What are virtual objects? In my view, they are digital objects, constituted by computational processes on a computer. To a first approximation, they can be regarded as data structures, which are grounded in computational processes which are themselves grounded in physical processes on one or more computers. To a second approximation, one may want to invoke more subtle relations between virtual objects and data structures, just as theorists often invoke more subtle relations between high-level nonvirtual objects (e.g. a statue) and underlying physical entities (e.g. a lump of clay). For example, in some cases, multiple data structures will be associated with a single virtual object, in which case the virtual object will be a higher-level entity constituted by these data structures. I will focus on the simple data structure view here, but much of what I say should generalize to more complex views.

Corresponding to each avatar in Second Life, there is a data structure on the Second Life servers (perhaps distributed redundantly across many servers). When I see an avatar, it is this data structure that brings about my perception. What I perceive directly reflects the properties of this data structure: the perceived location of the avatar reflects one property of the data structure, while the perceived size, color, and so on reflect other properties. When my avatar interacts with a coin, the two data structures are interacting. Whenever two virtual objects interact in Second Life, there is a corresponding interaction among data structures. Data structures are causally active on real computers in the real world; the virtual world of Second Life is largely constituted by causal interaction among these data structures.

This gives rise to the first argument for digitalism: the argument from causal powers.

• (1) Virtual objects have certain causal powers (to affect other virtual objects, to affect users, and so on).

• (2) Digital objects really have those causal powers (and nothing else does).

• (3) Virtual objects are digital objects.

Of course this is not a knockdown argument against the fictionalist. Fictionalists will probably deny the first premise by saying that virtual objects do not have causal powers, or better, that they have causal powers only in the sense that Gandalf has causal powers. That is, they have causal powers within a fictional world, and any effects on the real world are brought about not by the object but by a representation of the object. Still, even the nonconclusive argument from the premise that virtual objects seem to have these causal powers and that digital objects really have those powers is a reasonably strong one. If there are real objects that have all the apparent properties of virtual objects, there is not much reason to suppose that virtual objects really belong to a separate layer of fictional objects.

A closely related argument is the argument from perception:

• (1) When using virtual reality, we perceive (only) virtual objects.

• (2) The objects we perceive are the causal basis of our perceptual experiences.

• (3) When using virtual reality, the causal bases of our perceptual experiences are digital objects.

• (4) Virtual objects are digital objects.

Here premise (1) is intuitively plausible, and premise (2) is a widely accepted claim in the philosophy of perception. Premise (3) seems to be empirically correct. A data structure in the computer is causally responsible for generating my experience. One might suggest that an image on the display screen is the relevant causal basis, but a moment’s reflection suggests that this cannot be right: multiple people may see different images on different displays while they all perceive the same virtual object. Just as many people can see the same actor by watching TV on different screens, because that actor that is the causal basis for all the images, many people can see the same digital object by experiencing virtual reality with different displays, because that digital object is the causal basis for all the images.

Once again, this is not a knockdown argument. A fictionalist can reply that this is really a case of hallucination in which no real object is perceived. In some cases of hallucination, there is a causal basis for the perception: for example, a chair in the environment might trigger an auditory hallucination of a voice, but one does not hear the chair. Still, the fact that in this case there are objects that serve so systematically as the causal basis of the experience makes this line harder to maintain.

It is widely accepted that when we look at a photograph or a film clip

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