Nick Bostrom proposed that if advanced civilizations run many simulations, we are likely living in one.

Philosopher Nick Bostrom formulated an argument suggesting that among three possibilities, one must be true: human civilization will almost certainly go extinct before becoming technologically mature; advanced civilizations lose interest in creating ancestor simulations; or we are almost certainly living in a computer simulation. This argument has shaped much of the modern discussion around the topic, framing it as a serious philosophical and scientific question rather than mere science fiction.