Are We Living in a Simulation?

An argument before a hypothesis

Nick Bostrom’s 2003 paper does not simply declare that we live in a simulation. It argues that at least one of three propositions must hold.

Civilizations like ours almost never reach a posthuman stage; posthuman civilizations almost never run ancestor simulations; or, if they run vast numbers of them, observers like us are overwhelmingly likely to be simulated.

• Nick Bostrom, Are You Living in a Computer Simulation?

  The original paper setting out the trilemma and its probabilistic assumptions.

Probability rests on assumptions

The argument depends on simulated consciousness being possible, sufficient computing resources existing, and advanced civilizations choosing to run enormous numbers of ancestor simulations. None is currently established fact.

Whether a computation matching our experience would create consciousness, and which class of observers should ground the probability, remain philosophical disputes.

Would finding a trace prove it?

Proposals seek simulation traces in lattice structure, computational limits, or unusual constants. Without predictions that differ from ordinary physical theories, however, such observations cannot provide a decisive test.

Being able to explain an observation differs from predicting it better than rival explanations. The simulation hypothesis currently remains closer to a metaphysical and probabilistic argument than an established scientific theory.

Would virtual mean less real?

Even if a world were implemented by an external process, its suffering, relationships, and regularities would not disappear. Whether a world is simulated and whether lived experience is real may be separate questions.