The simulation hypothesis proposes that reality — including conscious experience — is the output of a computer simulation run by an advanced civilization. The idea has two distinct lineages: a mystical / psychological strain associated with Philip K. Dick (especially his 1977 Metz address), and a rationalist / probabilistic strain formalized by Nick Bostrom in "Are You Living in a Computer Simulation?" (2003).
For AI thinking, the simulation hypothesis functions as a thought experiment about the nature of intelligence, consciousness, and computation. If minds can be instantiated in any sufficiently capable computational substrate — biological neurons, silicon chips, or simulated processes — then there is no privileged substrate for intelligence. This position underlies much of the functionalist tradition in philosophy of mind and connects directly to debates about whether large language models can be conscious.
A notable recent development is the intersection of the simulation hypothesis with generative AI. When image-generation systems became capable of producing photorealistic scenes indistinguishable from photography, the epistemic question Dick and Bostrom raised became practical: what does it take to know that any given perceived image, or scene, or conversation represents a base-reality event? The question was formerly metaphysical; it is now forensic, and the forensics are losing ground.
Philip K. Dick's 1977 Metz address ("If You Find This World Bad, You Should See Some of the Others") is the pop-culture origin. Bostrom's 2003 paper in Philosophical Quarterly is the rigorous formulation.
Bostrom's trilemma. At least one of these is true: civilizations go extinct before simulating minds; or civilizations capable of such simulations choose not to; or we are almost certainly in a simulation.
Substrate independence. The functionalist premise that mind-properties depend on organization, not substrate.
Dickian variant. Emphasizes perceptual and gnostic intrusions rather than probabilistic argument — glitches and deja-vu as epistemological evidence.
Indifference of level. If we cannot tell whether we are in a simulation, the usual response — "so what, behave the same way" — is only partially correct. For any decision involving very long-run consequences, the expected value changes depending on whether the consequences are simulated or instantiated. The simulation question is therefore not purely philosophical; it enters (uncomfortably) into utilitarian calculation.