Simulation hypothesis

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A technologically mature “posthuman” civilization would have enormous computing power. Based on this empirical fact, the simulation argument shows that at least one of the following propositions is true:

(1) The fraction of human-level civilizations that reach a posthuman stage is very close to zero;

(2) The fraction of posthuman civilizations that are interested in running ancestor-simulations is very close to zero;

(3) The fraction of all people with our kind of experiences that are living in a simulation is very close to one.

If (1) is true, then we will almost certainly go extinct before reaching posthumanity. If (2) is true, then there must be a strong convergence among the courses of advanced civilizations so that virtually none contains any relatively wealthy individuals who desire to run ancestor-simulations and are free to do so. If (3) is true, then we almost certainly live in a simulation. In the dark forest of our current ignorance, it seems sensible to apportion one’s credence roughly evenly between (1), (2), and (3).

—Nick Bostrom, Are You Living in a Computer Simulation? (2003)

“I wish I could summon a strong argument against it, but I can find none.” — Neil Degrasse Tyson

An amusing, but fundamentally preposterous a priori argument which purports to prove by deduction, in the same way that Rene Descartes deduced the existence of rice pudding and income tax, that either we are as good as dead, or we do live in a Matrix.

To help Professor Degrasse-Tyson, here are some:

It’s an undecidability paradox

This means intelligent life capable of creating a Matrix is logically impossible. If you can do it, then you are a simulation, and you aren’t actually alive after all. If you can’t do it, then — clearly — you can’t be a simulation, but you must also be incapable of developing a difference engine that could create a Matrix, so you wouldn’t be having this conversation in the first place. We know we aren’t dead, so we must therefore be in a Matrix.

But, problem: unless intelligent life becomes capable of simulating itself — that is, creating a Matrix — there will be no Matrix. The definition of a Matrix is that it is a simulation of intelligent life. If there is no intelligent life to simulate, then, whatever a Matrix is, it can’t be a simulation. Could it be — the real thing?

Definitional problem: real life meets the definition of “a computer simulation”, especially if you go substrate neutral

For this to work, the simulation would not just have to be very good: it would need to be identical to real human sentience, in every respect. This would involve not just a perfectly accurate — that is to say transcendently true — theory of human cognitive activity, but a perfectly accurate — that is to say transcendently true — theory of all events in the universe. These theories would not be models as any sense of the word, but actual replications of the actual world, that is to say, the territory itself, not a mere map.

Any shortcuts would lead to potential variances, and as we know from our modern morality tales about, butterflies and rain forests, jointed pendulums and so on, any atomic variations in initial conditions have colossal, non-linear knock-on effects.

So firstly the sheer computing power required to run this algorithm would be so great as to not only be practically impossible, but theoretically impossible. In fact, its operation would not so much skew the functioning of the real-world, but but duplicate it: but but you cannot duplicate the energy in a closed physical system without violating the laws of thermodynamics.... unless the real world counts as a computer simulation. which on this logic it does. If a computer simulation is indistinguishable from the universe itself, then the universe is the computer simulation and this hypothesis is — semantics.

And about those laws of thermodynamics: in order to draw a complete, functioning, comprehensive theory of the universe, one must first have comprehensive, true, knowledge of the total canon of all laws of science. But science being an inductive process, and quite incapable of establishing anything by way of proof, this is again theoretically impossible. Our present state of knowledge of the laws of the universe is contingent and incomplete.