19 Aug 19
@lemondrop saidThere are hundreds of thousands of brains in a vat, just not alive.....
maybe?
I gather you have just watched Donavan's Brain.
19 Aug 19
@lemondrop saidBrains don't work without stimulation and interaction. So it'd have to be something like the permanent dream state Matrix in which the brain was tricked into thinking it was out there walking around.
more in the likes of the matrix
19 Aug 19
@wildgrass
But the matrix had people crashing into the digital world so THOSE brains were hooked to a living body, not a brain in a vat.
20 Aug 19
@sonhouse saidI really don't know what I'm talking about
@wildgrass
But the matrix had people crashing into the digital world so THOSE brains were hooked to a living body, not a brain in a vat.
20 Aug 19
@sonhouse saidIt doesn't matter whether the brain is being kept alive by a body or a life support system. One needs the entire nervous system though, just the brain would be a problem because one needs to know which fibre in the brain's junction with the spinal cord is connected with which nerve ending to give the brain inputs it can make sense of and to handle the outputs so the brain in a vat can interact with the world. This means one has to distinguish between sensory nerves and motor nerves and there are trillions of them. One would also need to simulate the body and let the brain think it's running an actual body rather than just getting random inputs. So the user experience, so to speak, is the same in the matrix films, where their entire bodies are in vats, as it is in the case of an actual brain in a vat.
@wildgrass
But the matrix had people crashing into the digital world so THOSE brains were hooked to a living body, not a brain in a vat.
The idea is that one cannot tell whether one is a brain in a vat or not. Any anomalies in one's perceived reality could be due to neurological events or due to glitches in a simulation. The prefrontal cortex, which is not active during dreaming, has reality checking as one of its functions. So, it seems likely to me that one could tell the difference if one's transference to a vat happened in adulthood - in a scenario where Dr Black, the evil neuroscientist, kidnaps someone, cuts out the brain and connects it to a machine that simulates reality. I think the victim would be able to tell the difference, unless the simulation was nearly perfect, which we just don't have the computational power for - we need to simulate an entire body. This leaves an entire lifetime in the vat, as then one's prefrontal cortex would only have one reality to work with. This seems somewhat pointless, except maybe as a way of giving people born with profound physical disabilities a normal life, but any civilization capable of a simulation this complex could probably prevent or cure the disability. So the only remaining option that makes any sense is that the entire brain is simulated. If the whole of reality is a simulation then it implies the existence of a higher reality in which the simulation is running. That reality needs to be bigger than the simulation, in some sense, since the constraints on our universe reflect limits on their computational power. So I don't think any of this is particularly plausible.
