Glongpre said:
It is still the same computer, if you still have the same programs and stuff it had before. If you didn't change where everything is stored (the brain), then it is still the same computer.
So, the follow up question there is, what constitutes a large enough change for it to become a "different computer". What if I install or uninstall a program - it now has a different subset - is it new? What if I move all software to a new location, e.g., to a new partition? And yeah, what if I change the partitions - go for 2 to 6 and spread the data among them? Would reinstalling the OS alter the computer? Would installing different OS change the computer, e.g., going from Windows 7 to Windows 10 or vice versa? Or installing Linux? If yes, then what about dual booting?
Then we can get more existential yet - would virtualising that setup lead to it being the same computer again?
And here is a more complex scenario built on top of the previous ones - say, we assume that adding or removing software doesn't constitute it being a "new" computer unless it's drastic (wipe all to factory settings and install completely different software, for example). And say, we also assume that virtualising the computer still keeps it the same. What happens if we virtualise the computer, destroy the original[footnote]effectively, that is - perhaps it's now a "different" machine because it's been wiped and repurposed[/footnote] then spin up two instances of this machine. Afterwards, we start changing them separately - uninstall one thing, install another, delete small amounts of data from one, add some to the other and so on and so forth. Over time, they start diverging until they look nothing alike - data is completely different, software is completely different. For the sake of the example, let's say they only keep the OS the same, but everything else has been changed and both instances now serve two completely different purposes, neither of which is like the original. Would both still be the same PC? Neither? Perhaps one?