On 14 Jan 2009, at 18:52, Quentin Anciaux wrote: > Hi, > > 2009/1/14 Brent Meeker <[email protected]> > > Stathis Papaioannou wrote: > > 2009/1/14 Brent Meeker <[email protected]> wrote: > > > >> However a Turing machine is not just a set of states, it also > requires a > >> set of transition rules. So in the same abstract way that the > integers > >> are ordered by "succession" the computational states of a Turing > machine > >> are ordered. Whether just abstract rules, without > implementation, are > >> sufficient isn't clear to me. > > > > In an actual physical computer the transition rules are > represented by > > the causal links between the states, so that a particular input will > > reliably give rise to a particular output. But I return to my > question > > about what would happen if there were a discontinuity in a > sequence of > > states, so that s1 to s10 on m1 are causally linked, s11 to s20 on > m2 > > are causally linked, but there is no link between m1 and m2, i.e. m2 > > just happens to start in s11 accidentally. Assuming that s1 to s20 > > occurring in a single machine results is a few moments of > > consciousness (which is to say, assuming that computationalism is > > true), what would happen if the sequence is broken in the way just > > described? > > I suspect something is lost. You are thinking of the states as > abstract steps > in a computer program. But a computer program requires a computer > to run and > the computer implements distributed spatiotemporal links. In > general you cannot > take even a digitial computer and freeze it in a instant of time, > call that a > state, and restart it without any effects. > > I do not see a problem with that... a program can be freezed any > time... dump the memory to a file, on restart, load the dump file to > memory, put the instruction pointer at the correct place and you're > done. (well in practice it is a little more difficult, but you could > do it for *any* program). In the situation that Stathis describe, > causality is not broken in any way. S1->S10 run in computer 1, dump, > reload on computer 2 S11->S20 run in computer 2, the causal link is > given by the program that compute S1-S20 irrelevant on what physical > device it is running on... the causal link is the program and a > program is relative to a machine (abstract one). So a computation is > the set of a program and the machine that runs it. A state doesn't > exists by itself (state of what ?), and this is where Stathis is > wrong I think.
Stathis is not wrong but seems unclear on what a computation mathematically is perhaps. Many miss Church thesis. The fact that there is a purely mathematical notion of computation at all. Best, Bruno > > > Regards, > Quentin > > Switches are in intermediate states, > EM waves are propagating, electrons are diffusing - it is not a > static thing > like a step in a program. > > In terms of Bruno's teleporter, one might say yes accepting that > there would be > a one-time gap in consciousness (ever had a concussion?), but one > would probably > hesitate if the there was to be a gap every 10ms. > > Brent > > > > > > -- > All those moments will be lost in time, like tears in rain. > > > http://iridia.ulb.ac.be/~marchal/ --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/everything-list?hl=en -~----------~----~----~----~------~----~------~--~---
