There is a lack of consistency between an implicit premise in Bostrom's argument and one in Feather's critique: >any posthuman civilization is extremely unlike

There is a lack of consistency between an implicit premise in Bostrom's argument and one in Feather's critique: >any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof); [emphasis added] >This lack of necessary overlap in metaphysics between the world that creates a simulation and the simulation itself could be called the simulation barrier. [emphasis added] Why would there be a lack of necessary overlap in metaphysics between the world an evolved organism inhabits and a simulation of its own evolutionary history? Bostrom's reasoning for why these simulations would exist in the first place clearly depends on extrapolating from various aspects of human behavior, so his argument necessarily posits that the beings running the simulations are at least in this way (and probably in others) similar to humans. The similarity of the Universe, largely, follows. Furthermore, the simulation argument fails to be really different from the dream argument when we omit Bostrom's motivation argument. If we can be in a simulation within matryoshkaed simulations thousands of layers deep, then surely we might be in a dream within a dream thousands of layers deep. We can provide all of the necessary metaphysical computational capacity to the dreamer that we would a simulator, can't we? The whole bit where creatures are motivated to simulate themselves seems, to me, to be crucial.