As computer simulations become more and more lifelike, the question could we be living in a simulation? becomes more interesting. Especially to fans of The Matrix movies.
But also to philosophers, since Plato, Descartes, and many others have wondered whether this world that we assume is real, actually is.
David Chalmers, a philosopher who is the codirector of the Center for Mind, Brain and Consciousness at New York University, has written a fascinating book: Reality+: Virtual Worlds and the Problems of Philosophy.
To recap, our three main questions about virtual worlds are the following. The Reality Question: Are virtual worlds real? (My answer: yes.) The Knowledge Question: Can we know whether or not we're in a virtual world? (My answer: no.) The Value Question: Can you lead a good life in a virtual world? (My answer: yes.)
The Reality Question, the Knowledge Question, and the Value Question match up with three of the central divisions of philosophy.
(1) Metaphysics, the study of reality. Metaphysics asks questions like "What is the nature of reality?"
(2) Epistemology, the study of knowledge. Epistemology asks questions like "How can we know about the world?
(3) Value theory, the study of values. Value theory asks questions like "What is the difference between good and bad?"
I'm enjoying the book, though I have to admit that it's hard for me to get my head around the argument that there's a very good chance we're living in a simulation, even as I'm forced to agree that Chalmers presents persuasive reasons for why this could be true.
Or even, almost certainly is true.
Chalmers engages in some sophisticated reasoning, thankfully in clear language. So it isn't possible for me to describe all of the nuances of his book in a few blog posts. I'll be content with writing about some subjects that particularly interest me.
Here's part of what he says about the Reality Question. I'll share this section in total, so you can get a feel for how Chalmers thinks through philosophical issues.
Whenever virtual reality is discussed, one hears the same refrain. Simulations are illusions. Virtual worlds aren't real. Virtual reality isn't genuine reality.
You can find this idea in The Matrix. In a waiting room inside the simulation, Neo sees a child apparently bending a spoon with the power of his mind. They engage in conversation:
CHILD: Do not try and bend the spoon. That's impossible. Instead... only try to realize the truth.
NEO: What truth?
CHILD: There is no spoon.
This is presented as a deep truth. There is no spoon. The spoon inside the Matrix is not real but a mere illusion. The implication is that everything one experiences in the Matrix is an illusion.
In a commentary on The Matrix, the American philosopher Cornel West, who himself played Councilor West of Zion in The Matrix Reloaded and The Matrix Revolutions, takes this line of thinking even further.
Speaking of awakening from the Matrix, he says, "What you think you're awakening to may in fact be another species of illusion. It's illusions all the way down." Here there is an echo of Vishnu: Simulations are illusions, and ordinary reality may be an illusion, too.
The same line of thinking recurs in the TV series Atlanta. Three characters are sitting around a pool late at night discussing the simulation hypothesis. Nadine becomes convinced: "We're all nothing. It's a simulation, Van. We're all fake." She takes for granted that if we're living in a simulation, we're not real.
I think these claims are wrong.
Here's what I think: Simulations are not illusions. Virtual worlds are real. Virtual objects really exist. In my view, the Matrix child should have said, "Try to realize the truth. There is a spoon -- a digital spoon." Neo's world is perfectly real. So is Nadine's world, even if she is in a simulation.
The same goes for our world. Even if we're in a simulation, our world is real.
There are still tables and chairs and people here. There are cities, there are mountains, there are oceans. Of course, there may be many illusions in our world. We can be deceived by our senses and by other people. But the ordinary objects around us are real.
What do I mean by "real"? That's complicated -- the word "real" doesn't have a single, fixed meaning. In Chapter 6, I'll discuss five different criteria for being "real." I'll argue that even if we're in a simulation, the things we perceive meet all these criteria for reality.
What about ordinary virtual reality, experienced through a headset? This can sometimes involve illusion. If you don't know you're in VR and you take the virtual objects to be normal physical objects, you'd be wrong. But I'll argue in chapter 11 that for experienced users of VR, who know they're using VR, there need be no illusion. They're experiencing real virtual objects in virtual reality.
Virtual realities are different from nonvirtual realities. Virtual furniture isn't the same as nonvirtual furniture. Virtual entities are made one way and nonvirtual entities are made another.
Virtual entities are digital entities, made of computational and informational processes. More succinctly, they're made of bits. They're perfectly real objects that are grounded in a pattern of bits in a computer. When you interact with a virtual sofa, you're interacting with a pattern of bits. The pattern of bits is entirely real, and so is the virtual sofa.
"Virtual reality" is sometimes taken to mean "fake reality." If I'm right, that's the wrong way to define it. Instead it means something closer to "digital reality." A virtual chair or table is made of digital processes, just as a physical chair or table is made of atoms and quarks and ultimately of quantum processes.
The virtual object is different from the nonvirtual one, but both are equally real.
If I'm right, then Narada's life as a woman is not entirely an illusion. Nor is Morty's life as a football star and carpet salesman. The long lives that they experience really happen. Narada really lives a life as Sushilla. Morty really lives a life as Roy, albeit in a virtual world.
This view has major consequences for the problem of the external world. If I'm right, then even if I don't know whether or not we're in a simulation, it won't follow that I don't know whether the objects around us are real.
If we're in a simulation, tables are real (they're patterns of bits), and if we're not in a simulation, tables are real (they're something else). So either way, tables are real. This offers a new approach to the problem of the external world, one that I will spell out over the course of this book.