I suppose you could argue that while a certain software can run on different machines, a particular running instance of that software is tied to its physical implementation. Such an instance can't be transferred to another machine (this would be just a copy), and is indeed lost when the computer is turned off and on again. Similarly, a certain consciousness (say, Jones-consciousness) may be realised in different brains, yet one particular conscious mind is inseparably tied to the very brain it is "running" on.walrii wrote:These discussions make the unspoken assumption that the human mind and body are two different things like hardware and software. Lines of code and data exist independent of the machine that runs and processes them. I'm am not convinced that the mind exists independent of the body. If we swapped out cells (hardware) no matter how exactly we attempted to replicate them, we could well end up with different a different mind (software) simply because the cells were almost identical but different.
I think this kind of argument does have some intuitive force, but I'm not sure it's conclusive. Suppose you replace one neuron of your brain with some kind of nano-device, which fulfils exactly the same function as the neuron; your memories, thinking, behaviour etc. do not change in any way. Surely you'd still consider yourself the same person!? Replace another neuron with a comparable nano-device... and gradually the whole brain. At which point would you say that the original mind is replaced by a different one, another self? Maybe at 50%? But then at some point it depends on one single neuron whether you're the same person or not... this seems to be a rather implausible consequence. Similar questions arise when your brain isn't replaced, but gradually transferred to a computer or something (see Keith Wiley 2015 for an interesting paper on that topic). Although this is certainly a very hypothetical scenario, it shows that the identity of a conscious mind probably isn't tied to the physical integrity of the brain the way you might be inclined to think it is.
