What possible world would that be? If it should turn out that the Italian government is engaged in a vast experiment to see how many people it can convince of a true thing using only very inadequate evidence (and therefore falsified the evidence so as to destroy any reasonable case it had), we could, in principle, discover that. If the simulation simply deleted all of her hair, fiber, fingerprint, and DNA evidence left behind by the salacious ritual sex murder, then I can think of two objections. First, something like Tyrrell McAllister’s second-order simulation, only this isn’t so much a simulated Knox in my own head, I think, as it is a second-order simulation implemented in reality, by conforming all of reality (the crime scene, etc.) to what it would be if Knox were innocent. Second, an unlawful simulation such as this might seem to undermine any possible belief I might form, I could still in principle acquire some knowledge of it. Suppose whoever is running the simulation decides to talk to me and I have good reason to think he’s telling the truth. (This last is indistinguishable from “suppose I run into a prophet”—but in an unlawful universe that stops being a vice.)
ETA: I suppose if I’m entertaining the possibility that the simulator might start telling me truths I couldn’t otherwise know then I could, in principle, find out that I live in a simulated reality and the “real” Knox is guilty (contrary to what I asserted above). I don’t think I’d change my mind about her so much as I would begin thinking that there is a guilty Knox out there and an innocent Knox in here. After all, I think I’m pretty real, so why shouldn’t the innocent Amanda Knox be real?
What possible world would that be? If it should turn out that the Italian government is engaged in a vast experiment to see how many people it can convince of a true thing using only very inadequate evidence (and therefore falsified the evidence so as to destroy any reasonable case it had), we could, in principle, discover that. If the simulation simply deleted all of her hair, fiber, fingerprint, and DNA evidence left behind by the salacious ritual sex murder, then I can think of two objections. First, something like Tyrrell McAllister’s second-order simulation, only this isn’t so much a simulated Knox in my own head, I think, as it is a second-order simulation implemented in reality, by conforming all of reality (the crime scene, etc.) to what it would be if Knox were innocent. Second, an unlawful simulation such as this might seem to undermine any possible belief I might form, I could still in principle acquire some knowledge of it. Suppose whoever is running the simulation decides to talk to me and I have good reason to think he’s telling the truth. (This last is indistinguishable from “suppose I run into a prophet”—but in an unlawful universe that stops being a vice.)
ETA: I suppose if I’m entertaining the possibility that the simulator might start telling me truths I couldn’t otherwise know then I could, in principle, find out that I live in a simulated reality and the “real” Knox is guilty (contrary to what I asserted above). I don’t think I’d change my mind about her so much as I would begin thinking that there is a guilty Knox out there and an innocent Knox in here. After all, I think I’m pretty real, so why shouldn’t the innocent Amanda Knox be real?