The Simulation Argument is an argument for the Simulation Hypothesis, first proposed in 2003 by Nick Bostrom. The important distinction between this and earlier simulation models has been the addition of a proposed method of engineering Simulated Reality through the use of computers and the assumption that the conscious beings themselves are simulated, rather than merely "brains in a vat". The argument also suggests that it is far more likely that we are living in a Simulation than we are not.
The concept was popularized by Nick Bostrom's paper "Are You Living in a Computer Simulation?" where he argues that one of following propositions is true: "(1) the human species is very likely to go extinct before reaching a “posthuman” stage; (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof); (3) we are almost certainly living in a computer simulation. It follows that the belief that there is a significant chance that we will one day become posthumans who run ancestor simulations is false, unless we are currently living in a simulation."
- Bostrom, Nick (2001,2003) Are You Living in a Computer Simulation Philosophical Quarterly (2003) Vol. 53, No. 211, pp. 243‐255.
- Bostrom, Nick (2011) A Patch for the Simulation Argument Analysis, Vol. 71, No. 1 (2011): 54-61