Criticizing the Simulation Argument
by, 08-18-2011 at 05:30 PM (796 Views)
One of the most important philosophical ideas of the 21st century is The Simulation Argument, laid out by Oxford philosopher Nick Bostrom. While some might dismiss it as silly, this would be a mistake. It deserves serious consideration.
While I won't delve into the in-depth mathematics of the argument, it essentially presents us with a three-way disjunct. Roughly, that disjunct is:
1. The chance of a given advanced civilization either destroying itself or getting destroyed before reaching a stage of technological development capable of running simulated consciousness is very close to unity (almost certain in non-math-speak).
2. The proportion of advanced civilizations interested in running simulated consciousness/actually pursuing simulated consciousness is very close to 0.
3. We are very likely living in a computer simulation.
It is worth noting that accepting this disjunct is technically all that's required for one to consider the Simulation Argument valid, because all the basic argument seeks to do is establish this disjunct. The Simulation Hypothesis is the idea that 3 is more likely than 1 or 2. I'm not sure I even accept the Simulation Argument, due to some issues I have with how Bostrom arrives at 3. For this reason, we shall start by examining 3 in and of itself.
The reason Bostrom considers 3 to be likely in the case of rejecting 1 and 2 comes from the notion of nested simulations - the idea that sim-worlds could themselves construct computers capable of running sim-worlds, creating another universe at another level of abstraction. The reason that this is important is that if nested simulations were commonplace, as they would be in Bostrom's universe, the number of simulated people would vastly outnumber the number of people in the base-level universe, and sheer probability would favor us being a sim.
Even if we accept Bostrom's disjunct, I still think we have many reasons to believe that 2 is far more likely than 1 or 3. The actual possibility of such simulations is highly suspect, or at least creating such simulations and hiding the fact that they're simulated from the program. The reason for this leads us into theoretical computer science - specifically, the Law of Leaky Abstractions. When I responded to the actual PerC thread about the Simulation Argument, the Law of Leaky Abstractions is the first objection that came to mind. Formally, the law states:
Any non-trivial abstraction is, to some extent, leaky.
Which in layman's terms means there's no way to completely isolate a simulation from its simulator. The implication here is that if we were living in a simulation, physics would probably show it. Specifically, I think we'd find an underlying pattern to quantum mechanics that has not yet been found (if they were being simulated - if our universe/multiverse is base-level, then they would not need an underlying pattern of this sort) and does not look likely given the Bell inequalities. The only assumption this objection rests on is the computability of experiences/laws of physics/whatever, which is necessary for the Simulation Argument in the first place.
Then there are motivation arguments. Supporters of the Simulation Hypothesis have suggested that advanced simulations would run sims for research purposes. However, imagine the effort involved. You'd have to overcome potential ethical opposition in your own civilization, and then once running the simulation constantly keep track of it to make sure the sims don't figure out too much. What would be the motivation for any civilization to create something that is clearly very difficult (if possible at all) to create, where they would constantly have to battle their own creation. If so much effort had to be put in to avoid the sims figuring out their situation, then would the research benefit be worth it? And then there are the economics of such simulations. This is not to say it's inconceivable that a civilization would either overcome or not face these obstacle, but it seems to me that the chance of any given civilization created simulations is actually close to 0.
My last, and perhaps most forceful argument, is a presuppositionalist one - that the Simulation Hypothesis epistemically undermines itself, as do all suggestions of a "transcendent" reality. All our reasoning, the basic cores of our thought and language, is built on the nature of our world. The entire Simulation Argument is constructed under the assumptions of our world. We cannot use our reasoning to posit the existence of something beyond our reasoning - this is invalid. To put it in simpler form, if we assume that we are living in a computer simulation, we are assuming that we can't assume we are living in a computer simulation. This of course is inconsistent with my earlier arguments, but the purpose of those is to illustrate that even if we suspend our epistemological concerns the Simulation Hypothesis is unlikely, in order to build a cumulative case against it.
I think together these constitute a good, rough cumulative argument against considering the Simulation Hypothesis remotely likely.
NOTE: Originally I has also incorporated a very long information-theoretic argument against the Simulation Hypothesis, but Bostrom has addressed this in his 2011 "Patch for the Simulation Argument."