Bostrom N. Are you living in a computer simulation? — Faculty of Philosophy, Oxford University [Published in Philosophical Quarterly, 2003. — Vol. 53, No. 211, pp. 243—255. (First version: 2001)]
This paper argues that at least one of the 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. A number of other consequences of this result are also discussed.