Posted by Estella on May 7, 2006, at 21:25:31
In reply to part-whole relations, posted by zeugma on May 7, 2006, at 15:36:26
> I just have a problem with calling a time-slice a 'part.' it does cause problems for self-identity and such. wildcard's amusing question, 'am i me again?' would have to be answered 'yes' we are ourselves again and again- and 'no,' because each time we ask the question we are a different part of ourselves, and so someone else (maybe). i did think her question was a little too deep for admin :-)
okay. i shall try... (just talking really...)
consider a branch. the branch has many parts. leaves. twigs etc. i think the notion behind four dimensionalism is that time slices are parts of the greater four dimensional space time worm. consider... fission (i think that is the right one - splitting - i get the terms 'fission' and 'fusion' confused, but i think 'fusion' is supposed to be joining). then consider my brain... suppose my hemispheres are dissected and each hemisphere is put in a different body (yeah yeah can't happen as a matter of fact but just grant me it is plausible in principle - even though it isn't given lower level structures and wiring and connection facts between low level structures and each hemisphere... but just grant Lewis his case of fission). then the notion is that there is person A and person B. trouble is that A does not equal B. but pre fission A is supposed to be identical to B, in fact even more strongly A is supposed to be numerically identical to B. Lewis thinks... that A never was identical to B and there were two objects (A and B) that were overlapping in space time prior to fission. So he thinks that there were actually two objects.But if people are just different time slices then what you have is time slice C is related to time slice D. (I thought this had something to do with the fission case but actually it doesn't seem to have a lot to do with it...). the notion is that C is related to D because of something to do with the causal path through space time. so technically speaking... if i want to do something tomorrow... it isn't that 'I' will get to do it. it is that some 'I' that is causally related to me will get to do it. it is a relative of mine that will retrieve the memory and execute the plan. there are problems... but i have some sympathy. for fragmentation over time and for fragmentation at a time...
i think the 'yes' and 'no' answer to 'am i me?' is okay. maybe true even. i am not the same time slice as was present yesterday. but i existed yesterday in the sense that both time slices are time slices of the same four dimensional space time worm. in the case of fission i think we get two distinct four dimensional objects that shared space time position / trajectory pre fission...
> anyway i see a disanalogy between an object's extension in time and its spatial extent.
okay.
> so i saw part of long island when i visited (and didn't miss much). let's say i saw <long island may 7 '06 2-7 am>. this is an object, no question.
i think lewis would say that you saw a particular time slice. the object wasn't wholly present because an object is not exhausted by its time slices. to become acquained with the whole object you would need to be acquainted with the whole space time worm. but you can grasp the object by considering it to be a space time worm i guess. you grasp that the object persists beyond your limited acquaintance of it. you grasp that it is an object that is further extended in space and time...
> and maybe i was the only one who saw that. the nearest someone else can come to that is someone who saw <long island may 7 '06 2-7:01 am>. now what the two of us saw sounds awfully similar. the component i missed is that minute after 7 am. but this is a gerrymandered object IMO.
thats okay... the other person saw a different time slice but it is supposed to be suitably causally related to the time slice you saw and it gets to be part of the same four dimensional object.
> anyway, it certainly is a Heraclitus' Paradox situation. the object <long island may 7 2-7:01 am> is fine, as a four-dimensional object, but then the problem i have is that its component parts are larger than the whole.
?
> Ie <long island> (the object) is a larger object, four-dimensionally, than the thing i saw this morning, but then it starts to sound like <long island> is actually a part of a proposition,
oh no i don't think it is supposed to be part of a proposition...
> and not a shorthand way of indicating ALL the time-slices of Long Island (which none of us can really gesture at or know). if so, then the object <long island may 7 '06 2-7:01 am> is one that awaits analysis (to be broken down into its component parts <long island>, <may 7 '06 2-7:01 am>). The latter object seems weird to me. Probably because time is more slippery than space.
?
> anyway, if <venus> (meaning the reference, not the sense/concept) is acceptable, then it enters into propositions as a part, and the predicates it mates with are not parts of it in turn. So 'Hesperus is Venus' is not logically complex, just Hesp=V.
um. i'm not really sure what to say... is 'branch' (the extension) logically complex? maybe maybe not... but it does seem to be ontologically complex. has leaves and twigs and chemicals and atoms and sub-atomic particles as parts. maybe 'venus' can be logically broken down into 'time slice1 and time slice2 and time slice3' etc. but i don't know...
> I don't know how to put identities into propositional form, because i am accustomed to seeing propositions as sets, and it doesn't matter how an object is indicated for set theoretical purposes. > are mystifying me at the moment.
me too. i've just seen p=p where people gloss that the = is supposed to stand for numerical / strict identity.
> The numbers 1 and 2 are parts, or rather elements, or better, members, of the set of natural numbers. So {1,2} is a subset of {1,2,3...}ah. it is talking of 'parts' that you are worried about... so if you think of 'branch' as a set then leaves and twigs etc would be members of the set...
> Say Earth is {E,W,N,S}. (We can imagine these as quadrants that meet at the core and include the atmosphere, ionosphere, etc.) Now no one's ever seen {E,W,N,S}. Then no one's ever seen Earth.
sh*t. okay i'm having trouble with this because they aren't equivalent in meaning... but maybe i need to think hypothetically lol.
> Not true. If we say that {E,W,N,S}is a good rendering of the meaning 'Earth', then if I say 'Earth is round,' then I indicate the proposition <{E,W,N,S}, R>. This is true-at-a-time, and false at others, for instance before the Earth existed as a discrete object. But it doesn't seem like those times are components of {E,W,N,S}. Rather is seems like {E,W,N,S} has certain properties at times. Sometimes it is visible from venus, sometimes not. But being visible from Venus is a property of {E,W,N,S}, not a part of it.okay. so some time slices are round and others are not. and the four dimensional object is round at some times and not round at others. and it gets to be that way in virtue of some time slices being round and other time slices not being round.
> It seems that properties and parts are very different.
hrm. not sure about the properties and parts thing...
maybe time slices don't really count as objects in their own right. maybe they are just parts of objects. i don't think they are meant to be properties... but they are supposed to be parts and the way those parts (time slices) are are the truth makers for the object having / not having various properties.but... time has to be discrete.
but... it ain't.
but... if it ain't then paradox ensues...
dammit.i went to a paper a couple weeks ago about how we like to think of an object as being wholly present at a moment.
but then we also like to think of an object as persisting through time.
there is tension between those (something has to give)we have time approaching... then receeding.
events loom in the future and then come to be and then receed into the past.
the object is wholly present but somehow it moves through time
(or perhaps time is like a stream that passes by the object)but...
time doesn't move.
my time slice is wholly present now.
my time slice pops out of existence
but another time slice (a relative of me)
will come to be in the next instant.
all there is (for this time slice)
is the now
time doesn't move
i do not move through time
there is only now.the notion is that if you see things this latter way...
it will decrease attachment and hence suffering
(this is the buddist view which seems consistent with current theorising on the nature of time and personal identity)but the trouble with this is that if you see things this way
you won't make plans form attachments etcand hence...
the illusion of an object that is both wholly present at an instant AND moving through time...
is a necessary illusion.
kinda like free will
kinda like free will methinks.crappy crap crap.
poster:Estella
thread:618106
URL: http://www.dr-bob.org/babble/write/20060331/msgs/641141.html