Simulation Hypothesis While many people take reality at face value, others believe the far more intriguing theory that we are living in a computer simulation. Bostrom states that if this is technologically possible, then it's virtually impossible that we aren't living in a computer simulation already. Such existential-sounding hypotheses often tend to be essentially untestable, but some researchers think they could find experimental evidence that we are living in a computer game… The theory that we are living in a computer simulation may sound bizarre, but it has found adherents.
That's because we can't assume that some other version of intelligent beings -- human or otherwise -- hasn't already hit that technological landmark and created a simulation in which we are now living.