Imagine for a moment you lived in a world with technology on the level of The Matrix. What I mean is that some Matrix-level technology - the ability to convincingly simulate an illusory environment - existed and was easily accessible.
Should the mere existence of this technology prompt one to be skeptical that the experiences they're having at any given time are real as opposed to illusory? Or at least, to greatly increase the odds that that may be the case?
I ask because it seems to me that one common reaction to brain-in-the-vat style thought experiments is, "Well, that's a science fiction scenario. It's fantasy." And of course, usually bitv style scenarios leave the environment untouched - you're just a brain in a vat, sans much context. Maybe "a mad scientist" is thrown in. But does the mere presence of the technology influence whether or not we should take that sort of skepticism seriously in the normal course of our lives? Do worries about being a brain in a vat become more pointed when you live next door to a R&D lab where there are thousands of brains in vats?
Now, no matter which way you answer that question, let me try another angle.
Should the mere fact that humans spend up to two hours per day dreaming cause us to be skeptical that the experiences we're having are real as opposed to illusory? Or at least increase the odds, etc.
Hopefully not, since otherwise we now find ourselves with a good reason to be very skeptical of day to day experiences. In fact, apparently around two hours out of the day we'd be *correct* to be skeptical! I don't see that pointed out very often.
Alright, let's go back to technology considerations again. Assume that the technology to convincingly simulate an illusory world is possible. Then it seems to me this is one (novel?) solution to the Fermi paradox: Beings who reach a suitable level of technological advancement sink into simulated realities as a rule.
At first that may seem unlikely - "there's so much out there to explore!" But is there, really? And how much of what's out there to explore needs to be visited to be explored? We can see quite a lot on the moon just fine from where we are. We can see quite a lot with a Hubble telescope too. Does that mean we want to go there? Do you really want to visit the freaking sun?
"But what about aliens? What about strange, foreign civilizations?" Good question - what about them? At a certain level of technological advancement, we'd be supposedly able to create those things, certainly virtually. Really, if we're able to simulate worlds and universes (and explore them as if they were real) it seems we'd have vastly more things to explore and see in our little neck of the woods than anywhere else. To put it another way, what would you find more interesting: Mars? Or the Matrix (that could, incidentally, contain any conceivable Mars-like planet)?
Of course, if we take it as a rule that advanced civilizations expand 'inward' rather than 'outward', and that they create simulations every bit as convincing as reality, we're swamped with skeptical considerations here and now - really, it looks like some version of Nick Bostrom's Simulation Argument kicks in. And, I maintain (and it seems Bostrom may well agree) that if the SA is regarded as true, then at least some form of theism must be regarded as true along with it.