My recent Intro to Apologetics video gave some examples of self-defeating statements. Here’s another example.
[Note: Nick Bostrom’s original argument makes a distinction between the argument and the hypothesis. The argument gives three possible options, and the hypothesis is that we are in fact in a simulation. The argument gives some evidence (some probability) that supports the hypothesis. This blog post is in response to the popular version of Sim Theory, not to Bostrom’s directly. Having said that, even with Bostrom’s version, to ever conclude that we are in a simulation suffers from the same problem.]
The logic of the Simulation Theory is this:
1. The end goal for sufficiently advanced humanoid species is to download their consciousnesses into a simulated world (alternatively, create virtual consciousnesses to inhabit virtual worlds).
Why would a civilization do this? A) It nearly creates immortality. The failings of a body don’t affect a computer program, lifetimes upon lifetimes can be simulated in short periods of actual time, and B) A computer system simulating anything could be much more energy efficient than sustaining a civilization of biological humanoids. Also, C) exploration beyond a few stars might not be possible but exploring endless virtual realities would be.
This seems like a very reasonable end goal, even inevitable, given a species survives long enough to develop to this stage of technology.
2. Now, these worlds could be duplicated endlessly, and would be indistinguishable from a real world to its inhabitants. Endless variety could be created, fantasy worlds with physics and metaphysics completely up to the programmer’s imagination.
So now we can step back and examine our own situation. Based on the sheer number of possible virtual worlds compared with the one actual world, it is far, far more likely that we are inhabitants of a virtual world than we are inhabitants of the real one.
3. Therefore, we should conclude that we are almost certainly living in a virtual, or simulated, world.
Ok, that’s simulation theory. Now there is plenty wrong with it. For example, we could question whether it’s even possible to “download consciousness” or whether minds are at all analogous to computers. But none of the questions we could raise against the premises would undermine this argument as much as its own conclusion does.
With the conclusion that we are in a simulated, virtual world in mind, let’s assume it’s true while we reexamine the premises:
1. The end goal for sufficiently advanced humanoid species is to create and then inhabit simulated worlds. Why? Because (a) biology is frail; a system like that could be much more energy efficient, because (b) computer systems can be efficient, (c) biological systems use lots of resources; and finally, exploration might be impossible because, (d) stars are very far apart from each other, and (e) space travel has difficult physical limitations.
2. We can extrapolate from (f) our knowledge of computers and simulations to know that these worlds could be duplicated practically endlessly.
The premises rest on these facts, among others:
a. Biology is frail
b. Computer systems can be energy efficient
c. Biological systems use lots of resources
d. Stars are very far apart from each other
e. Space travel has difficult physical limitations
f. Our knowledge of computers and simulations
How do we know the facts a through f? We know these things through our experience of the world around us. But considering our conclusion, the world around us is a virtual world that might not resemble the real world at all. In any case, we have no way of verifying or even a reason for guessing how closely a simulated world would resemble the actual world. In other words, (a) through (f) might not be true in the real world, for all we know. But the real world is precisely where these simulated worlds would originate from. But if, for all we know, (a) through (f) isn’t true of the real world, we have zero evidence for our argument’s premises, and so we are not rational to accept the conclusion that follows from those premises.
The conclusion of the argument undermines its own premises; it saws off the branch it’s sitting on.
Immortality isn’t a factor in simulation theory.
The virtual worlds are run as intellectual or curiosity exercises, much like many computer games.
You are right that there’s zero evidence of the premise. Which is why it’s just a thought experiment, albeit a compelling one.
Ok. Yeah, that seems to be the more prevalent version.
It doesn’t actually change the point though. Any evidence along the lines of “a real world would produce simulated world’s based on these lines of evidence from my observed world” would be undermined by the conclusion of “my world is probably a simulation.” It would be undermined because the observed world from which the evidence comes, is not the real world and might not be similar to it.