![[dr. bob]](/dr-bob-sm.gif)
Dr. Bob is Robert Hsiung, MD,
bob@dr-bob.orgShown: posts 8 to 32 of 32. Go back in thread:
Posted by agent858 on March 12, 2006, at 2:56:34
In reply to Re: z... talk to me..., posted by agent858 on March 12, 2006, at 2:45:31
and i might be getting a bit confused with the metaphysical / epistemic distinction.
metaphysical possibility...
the thought is that there are a number (maybe an indefinate number) of different possible worlds.
they are concrete (made of matter).
they are causally and spatiotemporally isolated from our world (which is why we can't see them etc) so our only evidence for them... comes from conceptual analysis (sounds strange to me)
"plurality of worlds" if you are interested...
epistemic possibility...
is supposed to be a description that is not contradictory. a complete description of a world. so... twin earth is just like earth except that the stuff that fills the lakes etc is made of xyz instead of h2o. there seem to be more non-contradictory descriptions (epistemic possibilities) than there are metaphysically possible worlds. so some epistemic possibilities (or described scenarios) seem to map on to worlds... while others do not.
sounds pretty strange huh.
Posted by agent858 on March 12, 2006, at 3:19:41
In reply to Re: z... talk to me..., posted by agent858 on March 12, 2006, at 2:56:34
though i don't think lewis makes the epistemic / metaphysical distinction...
Posted by Susan47 on March 12, 2006, at 9:35:12
In reply to Re: z... talk to me... » Susan47, posted by agent858 on March 12, 2006, at 2:20:20
Yes, dear, yourself ...
And I do apologize, as I am a bit latent with my intelligence .. if there is any ...
Good thing someone jumped in and changed my guess ...
but let's not draw any more attention to the matter.
Posted by zeugma on April 14, 2006, at 19:23:26
In reply to z... talk to me..., posted by 838 on March 9, 2006, at 20:46:16
> wanna talk to me about 2d semantics???>.
always up for that, especially when not blocked for a week :-)
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> do you have sympathy for something along the lines of fregean senses?
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yes.
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> hesperous is hesperous is cognitively insignificant (true a-priori) whereas hesperous is phosperous is cognitively significant (cannot be worked out a-priori)>>if hesperus is phosporus it is so, a priori. We are talking about the referents of hesperus and phosphorus. but '''hesperus' and 'phosphorus' share the same referent'' is a contingent fact of the language. so is "'hesperus' is hesperus." That is not an a priori truth on any account.
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> john believes hesperous is hesperous whereas even if john is perfectly / ideally rational he would not be expected to believe (without further info from the world) that hesperous is phosperous.>>hmm... suppose Hesperus were like Pegasus.... must one believe that Pegasus is Pegasus, if Pegasus does not exist?
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> and there are more... and these are supposed to motivate the thought that expressions don't just contribute the referent... they contribute a 'meaning' or 'sense' or 'mode of presentation' or somesuch as well...>>
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> then there are some arguments (kripke's modal argument and epistemological argument and some others) to show that there aren't any such things as fregean senses...
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> but then how to deal with frege's puzzles without fregean senses...
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> and then the 2d framework kicks in to try and deal with those cases...
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> so...
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> there are two ways in which we can evaluate an expression...
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> 'hesperous is hesperous' is necessarily true (it is true in all possible worlds). this is cognitively insignificant (it is knowable a-priori)... in any world in which hesperous exists... hesperous is hesperous...
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> 'hesperous is phosperous'. kripke... thought that this was necessarily true... in the sense that... in any world in which hesperous exists... hesperous is phosperous. another way of saying that... there is no possible world in which hesperous exists where hesperous is not phosperous. dammit... i need to learn how to do formal modal logic. can you do that?>>not really. but hesperus is phosporus necessarily, if we are talking about h and p de re. I can easily imagine hesperus and phosphorus as being separate objects. But then my thought is about something than Venus- I am not thinking about the planet with even more greenhouse gas than we have (presently), but about something mistier.
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> anyways... the thought is that kripke has shown us that there are expressions that are a-posteriori necessities... a-priori it is possible that hesperous is a different planet from phosporous... but given that hesperous is phosperous in the actual world 'hesperous' designates the object... which is in fact phosperous so the reference is fixed in the actual world and thus in all the possible worlds... hesperous is necessarily hesperous...>>we learn that this equation is true a posteriori. that is we extend our knowledge by equating the two. but 'a priori' and 'a posteriori' are relative terms, as their etymologies suggest. and so less significant IMO than philosophical tradition would suggest. From here it is far from evident that hesperus=phosphorus, but to whoever could live in those scorching greenhouse wastes, this planet=this planet is a fairly unexciting statement, where 'this planet'= Venus.
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> so that is metaphysical possibility...
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> then... there is epistemic possibility...
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> which tends not to be talked about as possible worlds... tends to be talked about as 'scenarios'. i think they are supposed to be... descriptions rather than worlds (there may or may not be a corresponding world for each epistemically possible description).
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> so... we can describe a situation (scenario) where things are just like they are now... except... instead of the star that appeared in the morning being the same as the star that appeared in the evening... there were in fact two different stars (or planets or whatever)... hmm.
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> so... the point is that epistemically... we cannot tell a-priori whether the scenario just described is our world or not... need to do some empirical investigation to figure it out. given the way this world turned out (the subjunctive conditional) it is necessary that hesperous is phosperous.>>because of where we are, some things, that to a Venusian hothouse flower (remember "The Day of the Triffids"- weren't they from Venus?) are obvious, can take the Babylonians as world-shaking revelation. This kind of thing happens all the time in astronomy. The 10th planet, or whatever it is, is afflicted by debate about what a 'planet' is. the fact is that since we lived on one, we didn't need more than an ostensive definition of the term 'planet.'
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> but if we were located (centred in) the scenario just described (if that world was the actual world) then... it would have been metaphysically necessary that hesperous was not phosperous.>>yes, location is everything.
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> so... there is talk of...
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> metaphysical possibility (determined by teh way the actual world turns out) need to see what worlds are possible...
> epistemic possibility (determined by what is conceivable - though i think that might be problematic...) but i think anything that is not a contradiction can be described as an epistemically possible scenario - which is to say our world could be this way for all we know at present).
>
> is this making any sense?
> have you read this stuff?>>the scenarios don't 'really' exist, if you want my uneducated opinion. A Venusian might be forgiven for not knowing that the Morning Star was the Evening Star, but we would not (ie. we are their Hesperus-Phosphorus problem). Their 'scenarios' regarding Earth would be non-contradictory, but would be hypothetical statements, and they would have to clean up their language once they got to know us better.
-z
Posted by zeugma on April 14, 2006, at 19:48:06
In reply to Re: z... talk to me..., posted by 838 on March 9, 2006, at 21:05:04
So... Lets describe a scenario (twin earth) where things are just the same as the actual world except that the clear watery stuff that fills the lakes and falls from the skies, the drinkable potable stuff is XYZ. Then the thought is that the correct thing to say is that... the stuff on twin earth (in the desctibed scenario) is not water. Are you okay with this? Do your intutions go along with Kripke / Putnam?>>
yes.
So... The thought is that given that water = H2O in the actual world... In all possible worlds (in which water exists) water is H2O. So... It is metaphysically impossible that water = XYZ because the reference of 'water' is fixed by the nature of the stuff in the actual world.>>
Water is an indexical term before it becomes a scientific one. You can refer to it as 'this stuff here' and express a fregean sense with that. 'this stuff here'= water=H2O. perhaps we would want to restrict 'H2O' only to water purified for use as a reagent or something (Chomsky makes this point). But allowing for impurities, water=H2O=this stuff my jacket is designed to repel. Now I could have been abducted to twin Earth when I left the apt., and my jacket is spattered with unusual molecules. This would be surprising (but in New York anything can happen). If investigated it would be called something other than 'water.' 'This stuff here' would express a novel Fregean sense, when used in this context; note that I might not have access to this bit of sense (no priviliged access to senses- no wonder we spout so much nonsense habitually). I suppose this is basic externalism.
-z
Posted by special_k on April 16, 2006, at 9:37:09
In reply to Venus calling » 838, posted by zeugma on April 14, 2006, at 19:23:26
> if hesperus is phosporus it is so, a priori.
ooh. what do you mean by a priori?
i thought a priori / a posteriori were epistemic notions. something that is knowable a priori is something that that can be known on the basis of conceptual analysis, whereas something that is knowable a posteriori is something that can be known on the basis of looking to the world. some things might only be knowable a posteriori (that water=h2o and that... hesperous is phosperous). some other things might only be knowable a priori (though testimony excepted i guess) like mathematics and logic. mathematics and logic seem to be knowable both a priori (when one does a deduction) and a posteriori (when one believes the answer the teacher gives you).> We are talking about the referents of hesperus and phosphorus. but '''hesperus' and 'phosphorus' share the same referent'' is a contingent fact of the language.
ooh. do you mean we could have said 'gavagai' and pointed to the sky instead of saying 'hespherous'? the word / referent relation is contingent, yup... but given that we pointed and said 'hesperous' and pointed and said 'phosperous' it turns out that hesperous (the object pointed to) is phosperous (the object pointed to). and that latter point (about x and y being the same object) is thought to be a matter of necessity (given that they are identical in the acutal world hesperous - the object - is identical to phosperous - the object - in any world in which the object exists.)
> so is "'hesperus' is hesperus." That is not an a priori truth on any account.
i think the idea is that 'x is identical to x' is an analytic / a priori truth that we can grasp from the armchair.
> hmm... suppose Hesperus were like Pegasus.... must one believe that Pegasus is Pegasus, if Pegasus does not exist?
er... yes non existent objects (and negative existentials - 'santa claus does not exist') were two other motivations for fregean senses / primary intensions. personally... i think pegasus exists as a primary intenstion / an idea / a description. much like sherlock holmes (and of course it is TRUE to say sherlock holmes lives in baker street even though there is no such thing as sherlock holmes in the world there is such a thing as sherlock holmes the fictional character and yup that is how the story goes...)
> but hesperus is phosporus necessarily, if we are talking about h and p de re.er... de re (object). de se (i forget... idea?). de dicto ('hesperous'). is that like dog (object) DOG (concept) and 'dog' (word). yep the object picked out by 'hesperous' and the object picked out by 'phosperous' are the same object in the actual world (we had to look to see so this is a posteriori rather than a priori we couldn't have figured it from our armchair). any described scenario in which the object picked out by 'hesperous' and the object picked out by 'phosperous' is not the same object... the appropriate way to describe the world is to describe it as one in which either hesperous or phosperous or perhaps both don't exist.
> I can easily imagine hesperus and phosphorus as being separate objects.
you can imagine (a priori) a world in which the object picked out by 'hesperous' and the object picked out by 'phosperous' were actually different objects. sure you can. thats why the a posteriori discovery that hesperous= phosperous was a significant astronomical discovery...
> 'a priori' and 'a posteriori' are relative terms,
are they solely epistemological terms or do they come up in other contexts? are they about ways of knowing...
> The 10th planet, or whatever it is, is afflicted by debate about what a 'planet' is. the fact is that since we lived on one, we didn't need more than an ostensive definition of the term 'planet.'
yeah that is funny. i'm thinking planets aren't natural kind terms... maybe they are more like 'large rock' which isn't a natural kind term either...
> yes, location is everything.yeah. some people like the idea of relativised possible worlds. so we can consider some possible worlds as actual from their point of view. (so we can evaluate a twin earthians claim 'water is h2o' as false in her context of utterance). other people say utterances should be evaluated in the context of the actual world. maybe it depends on how seriously you take possible worlds...
> the scenarios don't 'really' exist, if you want my uneducated opinion.
yeah. that is the idea. possible worlds exist (if Lewis is to be believed). but the thought is that scenarios... are just consistent descriptions (ie descriptions which aren't ruled out a priori as desctiptions of a possible world because they are consistent). but then we figure out stuff about the way this world is... and we realise that while twin earth might be a consistent desctiption... twin earth is not hte acutal world.
> I could have been abducted to twin Earth when I left the apt., and my jacket is spattered with unusual molecules. This would be surprising (but in New York anything can happen). If investigated it would be called something other than 'water.' 'This stuff here' would express a novel Fregean sense, when used in this context; note that I might not have access to this bit of sense (no priviliged access to senses- no wonder we spout so much nonsense habitually). I suppose this is basic externalism.
why the same fregean sense?
would they have the same primary intenstion?
if the primary intenstion is 'watery stuff' then the watery stuff on earth and twin earth has the same primary intension / sense.
it is just the referent that is different.
but externalism seems to be infecting primary intensions :-(
er... on a slightly related note... i have been hearing a little about 4d objects... and if that is right... if that is right...
that an object is not wholly present but a time slice is wholly present. and the time slice is related to the next time slice is related to the next time slice and the object is the whole 4d space-time worm... then objects don't change... er...
anyway... if this is right...
i think hesperous doesn't = phosperous (hence they are not identical necessarily)
i think hesperous is 'venus in the morning'
and phosperous is 'venus in the evening'
(hope i got them the right way around)
and venus... is the greater object. they are time slices of venus...what do you reckon?
Posted by zeugma on April 25, 2006, at 21:55:25
In reply to Re: Venus calling, posted by special_k on April 16, 2006, at 9:37:09
<<
'''hesperus' and 'phosphorus' share the same referent'' is a contingent fact of the language.
so is "'hesperus' is hesperus." That is not an a priori truth on any account.>>i think the idea is that 'x is identical to x' is an analytic / a priori truth that we can grasp from the armchair.>
'x is identical to x' and "'x' is x'" do not share the same logical form. "'x' is identical to x" is indeed analytic, and of the same logical form as 'x is identical to x', because the 'is identical to' construction is a disquotational operator- consider a Venusian saying "'Venus' is what you call our stifling hothouse of a globe." 'Venus' there is appropriately in quotes (as not being a part of the Venusian's native speech) but it is explicitly stated as being extensionally equivalent to the description the alien used.
sorry for being so pedantic, it's my nature.
miss you here
((((Special K)))))
-z
Posted by zeugma on April 25, 2006, at 22:28:30
In reply to Re: Venus calling, posted by special_k on April 16, 2006, at 9:37:09
i think hesperous is 'venus in the morning'
and phosperous is 'venus in the evening'
(hope i got them the right way around)
and venus... is the greater object. they are time slices of venus...what do you reckon?>>
hesperus is a name of Venus. 'hesperus is phosphorus' is true, but if hesperus meant 'time slice A of venus' and phosphorus meant 'time slice B of venus', 'hesperus is phosphorus' would be a contradiction.
i am staying up too late
-z
Posted by Estella on May 7, 2006, at 6:10:31
In reply to Re: Venus calling, posted by zeugma on April 25, 2006, at 22:28:30
>>'''hesperus' and 'phosphorus' share the same referent'' is a contingent fact of the language.
so is "'hesperus' is hesperus." That is not an a priori truth on any account.
sorry for being so pedantic, it's my nature.lol. That is okay. Sorry I read that you were saying venus is venus (the object is identical to itself) is contingent... I missed the quotation marks oops.
> i think hesperous is 'venus in the morning'
> and phosperous is 'venus in the evening'
> (hope i got them the right way around)
> and venus... is the greater object. they are time slices of venus...
> what do you reckon?>>
> hesperus is a name of Venus. 'hesperus is phosphorus' is true, but if hesperus meant 'time slice A of venus' and phosphorus meant 'time slice B of venus', 'hesperus is phosphorus' would be a contradiction.yes. so i guess i'm denying that 'hesperous is phosporous' is true. counterintuitive perhaps... but i reckon thats a better account. hesperous is a time slice of venus and phosperous is a different time slice of venus and so hesperous is a part of venus rather than being strictly identical to it. and phosperous is a (different) part of venus rather than being strictly identical to it. and thus hesperous does not equal phosperous. But they are both (different) parts of venus.
i have seen a similar account of the clarke kent / superman relation. they are both different time slices of (whatever his name is) - the body / person from whatever planet he is from. that way you can say 'superman wears glasses' is false while 'clarke kent wears glasses' is true.
that way you can say 'hesperous appears in the morning sky' is true (if it is indeed 'cause i might have them the wrong way around) and 'hesperous appears in the evening sky' is false. and 'phosperous appears in the morning sky' is false. and 'phosperous appears in the evening sky' is true. and different parts of venus appear in the morning and evening sky. and you can get yourself a nice account without needing to countenance fregean senses ;-)
(though i like fregean senses...)
just like the guy from wherever planet he is from sometimes wears glasses and othertimes not... because the clarke kent time slice wears glasses while the superman time slice does not...
what do ya think?
(maybe ontologically bloated... three objects instead of one... but if you want one object you need how many fregean senses? three i do believe (plus one object) or maybe only two plus an object? surely venus is a different concept from either hesperous or phosperous...)
?
Posted by zeugma on May 7, 2006, at 9:20:59
In reply to Re: Venus calling » zeugma, posted by Estella on May 7, 2006, at 6:10:31
>
>
> > hesperus is a name of Venus. 'hesperus is phosphorus' is true, but if hesperus meant 'time slice A of venus' and phosphorus meant 'time slice B of venus', 'hesperus is phosphorus' would be a contradiction.
>
> yes. so i guess i'm denying that 'hesperous is phosporous' is true. counterintuitive perhaps... but i reckon thats a better account. hesperous is a time slice of venus and phosperous is a different time slice of venus and so hesperous is a part of venus rather than being strictly identical to it. and phosperous is a (different) part of venus rather than being strictly identical to it. and thus hesperous does not equal phosperous. But they are both (different) parts of venus.>>counterintuitive, yes. (but when was that ever a problem in philosophy?? :)
> i have seen a similar account of the clarke kent / superman relation. they are both different time slices of (whatever his name is) - the body / person from whatever planet he is from. that way you can say 'superman wears glasses' is false while 'clarke kent wears glasses' is true.
>Krypton (where all cryptic problems come from).
superman wears glasses=true.
when he is clark kent. just like i wear clothes when i leave the apt. just like venus is visible, although not during day. and mercury can be seen by the naked eye, though it can't from where i am, and for all i know it was visble to Galileo with the naked eye but pollution has obscured it everywhere now. 'wears glasses' is hanging a predicate on superman. now it carries the wrong force (it implies that he wears them while in his cape and tights). clark k wears glasses= true. clark kent is superman= true. superman wears glasses= true if you see 'is' as denoting the identity sign, which it is (IMO). but i may wear glasses, and yet at the moment 'z wears glasses' is false. problems of tense. if i take the extension of 'wears glasses' as denoting everyone who ever wore them, at any time, then superman did wear glasses, though he did his best to disguise the fact that he did, and 'z wears glasses' is true too, though only when i put some on at a friend's urging and got dizzy and had a headache and will never do so again. it is an unnatural construal of 'wears glasses.' 'the shower is broken' is true, though hopefully that will change soon. But material implications are notoriously weak. Grice has something about force of conditionals, that i couldn't understand at all when i read it, but maybe it will shed light now.
> that way you can say 'hesperous appears in the morning sky' is true (if it is indeed 'cause i might have them the wrong way around) and 'hesperous appears in the evening sky' is false. and 'phosperous appears in the morning sky' is false. and 'phosperous appears in the evening sky' is true. and different parts of venus appear in the morning and evening sky. and you can get yourself a nice account without needing to countenance fregean senses ;-)(though i like fregean senses...)>>i like them too. but i think that a time-slice is not a part of something. surely one can fix a moment in time as 'this one', and then one relativizes objects to this, ie 'phosphorus' is 'venus now'. we can say that this relativization is that of dawn over babylonia. then 'phosphorus' is not 'hesperus.' 'phosphorus' is not 'venus' either. the problem is that one then has a term ('phosphorus') that is unlike say "Earth", which comes out the same regardless of time. It's Heraclitus' paradox- you don't step twice into the same river. or rather a variant, you see 'phosphorus' is not the same as the object you see at sunset (ive got them backwards, ah well) but most other things are the same. one can certainly do this. in fact this has a sense and referent. but the babylonians did not do this, they thought that hesperus and phosphorus were not broken down relative to times in this way, they thought they were broken down relative (i suppose) to the identity sign. that was an error.
i think.
>>
>
> (maybe ontologically bloated... three objects instead of one... but if you want one object you need how many fregean senses? three i do believe (plus one object) or maybe only two plus an object? surely venus is a different concept from either hesperous or phosperous...)>>well, things get tricky here. venus is an object, not a concept. frege as i understand him thought that predicates were denoting terms for concepts. 'is venus' then becomes systematically ambiguous. because 'is venus' sounds like a predicate, though it is more apt to sound like part of a statement affirming identity (using the identity sign). 'is red,' 'is hot, 'is venus.' i suppose my intuition is that those three are not of a kind. but i miss things, so.
-z
>
>
Posted by zeugma on May 7, 2006, at 13:49:43
In reply to Re: Venus calling » Estella, posted by zeugma on May 7, 2006, at 9:20:59
the babylonians did not do this, they thought that hesperus and phosphorus were not broken down relative to times in this way, they thought they were broken down relative (i suppose) to the identity sign. that was an error.>>
i meant, they thought pre-discovery that hesperus and phosphorus broke down relative to the identity sign.
i am breaking down, not relative to the identity sign, but end-of the-week sleep problems. Provigil is no good for this, my second vivarin may help, it helps the headaches that are post-cataplexy too.
-z
Posted by zeugma on May 7, 2006, at 14:58:23
In reply to Re: Venus calling » Estella, posted by zeugma on May 7, 2006, at 9:20:59
that way you can say 'hesperous appears in the morning sky' is true (if it is indeed 'cause i might have them the wrong way around) and 'hesperous appears in the evening sky' is false. and 'phosperous appears in the morning sky' is false. and 'phosperous appears in the evening sky' is true. and different parts of venus appear in the morning and evening sky.>
true that these pairs about hesperus and phosphorus have the truth conditions you state- in the Babylonian (or Greek, actually) dialects.
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 :-)
anyway i see a disanalogy between an object's extension in time and its spatial extent. 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. 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.
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, 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. 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.
Provigil, Vivarin, headache.
-z
Posted by zeugma on May 7, 2006, at 15:36:26
In reply to with reference to wildcard, posted by zeugma on May 7, 2006, at 14:58:23
are mystifying me at the moment.
(and i should be doing something else atm- but )
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...} But say I saw part of L.I, say A. Now L.I is composed of A, B, and C. That means that it just is that set {A,B,C}. 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.
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.
It seems that properties and parts are very different.
-z
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.
Posted by zeugma on May 7, 2006, at 23:08:19
In reply to Re: part-whole relations, posted by Estella on May 7, 2006, at 21:25:31
> > 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.
>
ok. There are two objects that I am as I speak. And one can be put in one body, another in a second. (if I understand this at all) I am composed of parts. OK. kant had trouble explaining the indexical 'I', so have others. I'm not convinced by Lewis' arguments, but 'I' is a concept in need of explanation too, an explanation I can understand :-)> 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...>>
fragmentation is fine. But...this is too strong a realism for me. Because there really is no relation (I would claim) between myself and a future time slice, because the future may be indeterminate for all we know, and so my relation to time slice C may not be one that exists (speaking crudely, up too late).
>
> 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...>perhaps that will become the dominant mode of reproduction i the future. certainly less messy than sex (joking)
>
> > anyway i see a disanalogy between an object's extension in time and its spatial extent.
>
> okay.that is really the crucial point for me. and maybe i am a 'spatialist', prejudiced in favor of objects spatially defined rather than four dimensionally.
>
> > 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.
>
ok, but it doesnt seem to be causally related. it seems to be a similarity that relates them. and that is a property. (ok i can't do better this time of night...)> > 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.
>
> ?
didnt elaborate. will further on.
> > 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...
>
ok. I saw this object defined as above (long island etc.) Call it 'S.' 'S' is a name, not a proposition. I can say, "S was a particularly uninteresting chapter in L.I.'s history." S is an object with definite identity conditions. But S appears to naturally come apart into a spatial extent (Long Island) and a temporal one (may 7 etc.). That may be a product of our manner of perception. But we have 'S'. And it looks to be an intersection of four dimensions, where S is the intersection of the time we represent as 'may 7 etc.' and the place we call 'Long island.' You must realize, verificationist that i am, that I would be skeptical about how Long Island extends into the future indefinitely. But no question, S may be a useful construct. But it still an object of a strange kind, and for instance, if we take it as the convergence of two elements, then we are still stuck with dianalogies. Because the spatial element is localized, but the temporal, not. Presumably it is 'may 7' (not clock time but real time, whatever that is) everywhere, that intersects with LI to form S, and with Manhattan to form Y, and so on. And LI persists, at least prima facie, but 'may 7' is instantiated only once. Hence, my qualms about disanalogy. And S seems to be equally a part of the LI worm and 'may 7 etc.', a temporal object. Which is interesting, but my head's too addled to focus now.
> > 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.
>
You see how I want to view it as an intersection, in which two objects meet, but still, we have say main Street and Pacific Boulevard and we don't worry about the ontology of the intersection. A street would be a worm to a flatlander. Too addled. The ideas are interesting though.
>
> > 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...
>
well, S is a part of LI, because it is an intersection, just like Main St. has a part that is an intersection. No problem.
> > 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...
>ok. S is a part of LI, and T is the one right after. But S is arbitrarily defined as may 7 etc., and I can plot infintely many different time-values onto LI. I can't do that with LI, conventionally defined. But Im missing something here, I know.
>
> > 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.
>
ok.
> but... time has to be discrete.
> but... it ain't.
> but... if it ain't then paradox ensues...
> dammit.
time doesn't seem discrete. if it isn't we can plot out series of intersections such as S and T, but the worm doesn't appear because there are no end points that aren't arbitrary.my muddled head, you have fascinating ideas E.
-z
> 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 etc
>
> and 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.
>
Posted by zeugma on May 7, 2006, at 23:16:04
In reply to Re: part-whole relations » Estella, posted by zeugma on May 7, 2006, at 23:08:19
. S is a part of LI, and T is the one right after. But S is arbitrarily defined as may 7 etc., and I can plot infintely many different time-values onto LI. I can't do that with LI, conventionally defined. But Im missing something here, I know>
i meant to say, S being arbitrary can be mapped onto LI and T can be mapped onto LI too, and then the conjunction of S and T is like a continent is to an island. very interesting... do may 7 and may 8 bear a similar relation that LI and Manhattan Island do? ie, same type, different onjetcs (both islands). can we get times that are as categorizable as spatial constructs (islands, continenets, oceans)?
interesting.
-z
Posted by Estella on May 8, 2006, at 1:05:13
In reply to Re: part-whole relations » Estella, posted by zeugma on May 7, 2006, at 23:08:19
> ok. There are two objects that I am as I speak.
well... that is tricky. hard to know whether there can be two objects that share the same space time worm as a matter of fact, or whether you only get two objects in virtue of fission occuring at a later point in time. i think the notion is that only when fission happens are we justified in saying there were two objects all along. i guess i have trouble with backwards causation, but apparantly that doesn't entail that and there is no problem with backwards causation there though i can't remember / see why not...
> And one can be put in one body, another in a second. (if I understand this at all) I am composed of parts.
IF fission is in your future, yup. If not... Then I don't think so. But that is in the fission case. Fission case aside you are still composed of parts. Time slices. In fact in the fission case you share common time slices in the past it is just the future time slices (from point of fission) that are no longer identical.
> But...this is too strong a realism for me. Because there really is no relation (I would claim) between myself and a future time slice, because the future may be indeterminate for all we know, and so my relation to time slice C may not be one that exists (speaking crudely, up too late).
Do you believe that we can evaluate claims about the future now? If I say... 'On October the 6th 2006 and six it will rain in New York'... Then this statement is either true or false right now (though we won't be in a position to evaluate it until then). Also need a clause about the ambiguity of rain... But do you think there are facts about the past that exist eternally (ie we don't have to wait for the truth maker... our statements about the future are either true or false now we don't have to wait)? Because if you do think that... Well then I guess statements about your future time slices (including statements about their relational properties) will be either true or false now...
What is the relation between time slices?
there things start to get a bit dodgey... I think Lewis went with a Lockean memory criteria.
Think Lewis re possible worlds and counterparts for a moment. There the notion is that your counterpart is the individual on that world who shares the most properties with you. Then back to the relation between time slices. There the notion is that the time slice that shares the most properties with that time slice in the next instant in time gets to be the next time slice of you. But of course one might want to tighten that (and maybe lewis does - not sure) with something to do with one time slice being causally related to the previous. but then there are problems for Lewis' account. consider some time slices within an individual
A -> B -> C -> D -> E
so A might be a time slice of you when you were 4
and B might be a time slice of you when you were 8
or whatever. point is time is moving left to right. now the problem is that it seems possible in principle for C and E to share more psychological properties than D and E. i think that creates problems for Lewis' notion of continuity.(though i'm not so sure... consider MPD / DID)
> perhaps that will become the dominant mode of reproduction i the future. certainly less messy than sex (joking)
yes. aka cloning. that seems to me to be a case of fission...
> that is really the crucial point for me. and maybe i am a 'spatialist', prejudiced in favor of objects spatially defined rather than four dimensionally.okay. though there is meant to be conflict between:
an object is wholly present at one point in time
and
objects change over time
the thought is you can't have both something has to give you have to choose...
so four dimensionalists say righto then an object is not wholly present at one point in time... rather a time slice is present.> ok, but it doesnt seem to be causally related. it seems to be a similarity that relates them. and that is a property. (ok i can't do better this time of night...)
yeah. actually to be fair i'm not sure that lewis talks about causal relationship. he talks about sharing of properties and similarity relation. i think i'm the one to bring causation into it and maybe i shouldn't have. sorry about that. i think it comes of the notion that i want decisions i make today (and beliefs i form today and desires i form today) to CAUSE my future time slices to be a certain way. but so long as they share the properties i guess it doesn't really matter...
> But S appears to naturally come apart into a spatial extent (Long Island) and a temporal one (may 7 etc.).
but... space-time is supposed to be a single dimension...
> Because the spatial element is localized, but the temporal, not.
you only have a thing insofar as it persists through time
you only have time insofar as you have things changing
they are two aspects / sides of the same... thing? dimension? whatever... but i agree that this sounds counter-intuitive.
the notion is just like there are spatial parts to things (and things can be divided by cutting them up into spatial parts)
there are temporal parts to things (and things can be divided by cutting them up into temporal parts)
and what you end up is things that exist unchanging for a discrete moment (time slice).consider
A -> B -> C -> D -> E -> F
Here we have an object (let us call it G)
G is the whole four dimenstional space time worm consisting ofA -> B -> C -> D -> E -> F
G doesn't change. though it might pop into existence before A and pop out after F.
A, B, C etc are time slices of G. I don't think they are objects in their own right... But there are time slices of G. I guess I was thinking of causal but lets forget the -> as causation at the moment and consider that A -> B just means that A and B overlap in their properties more than A and C. The notion is that A, B, C, etc have different properties. hence... things change. time slices have different (though similar) properties.
But G doesn't change. It is the whole worm.
Problems include...
How long is a time slice anyways.
(heh heh).On Fission we have...
A -> B -> C -> D -> E -> F -> K -> L
A -> B -> C -> D -> E -> F -> M -> NWhere the fission occurs after F
Clones work like this too...
It is only because of the fission that Lewis thinks we are warranted in saying there were two distinct objects all along.But I could be misunderstanding completely...
I don't really know what to make of it...
Posted by Estella on May 8, 2006, at 3:33:09
In reply to Re: part-whole relations » zeugma, posted by Estella on May 8, 2006, at 1:05:13
actually... i guess G does change...
it is the time slices that don't changei don't know whether a time slice counts as an object
or whether it is just supposed to be a part of an object.
we could imagine objects whose presence is totally exhausted by a time slice
a subatomic particle that has a brief moment of existence
why couldn't i be like that?
dammit
and why should i care about my relations (the other time slices)?
because the 'I' refers to them
the I refers to the space time wormbut that begs the question
why should i care about that?
Posted by Estella on May 8, 2006, at 3:34:16
In reply to Re: part-whole relations, posted by Estella on May 8, 2006, at 3:33:09
isn't this time slice done yet?
dammit
Posted by Estella on May 8, 2006, at 3:57:07
In reply to Re: part-whole relations, posted by Estella on May 8, 2006, at 3:33:09
> actually... i guess G does change...
> it is the time slices that don't changeActually... I'm not so sure... I'm not so sure what to say about that.
A - B - C - D - E - F
And the sum total of that = G
Does G change through time?
G just is the totality of slices.
Does G change through time?
Time slices change...
Each individual time slice doesn't...
But there are alterations in properties between time slices.
I guess you can say that the object changes at different points in time.
But G isn't located in any one point in time.
I'm not sure why I heard someone say that 4D objects aren't supposed to change...
I don't know.
I think this line is supposed to be an attempt at a solution of paradoxes around
Changing
and
Not changing
too
But I'm not sure...
And on this account how many ships of Thesus are there?
Ak.
Posted by Estella on May 8, 2006, at 4:03:24
In reply to Re: part-whole relations, posted by Estella on May 8, 2006, at 3:34:16
this looks good (not that i've read it)
http://www.oxfordscholarship.com/oso/public/content/philosophy/019924443X/toc.html
and stanford encyclopedia is pretty good too:
http://plato.stanford.edu/entries/time/#8
(i'm new to this stuff...)
Posted by Estella on May 8, 2006, at 4:11:20
In reply to Re: part-whole relations, posted by Estella on May 8, 2006, at 4:03:24
Ah.
If I am wholly present now (t1)...
And wholly present tomorrow (t2)...then t1 and t2 must share all the same properties.
because if x and y have different properties then x and y cannot be the same thing (by leibniz law)
and thus if there is numeric identity between x and y (me at t1 and me at t2) then how is it possible for x and y to have different properties?
i think that is one of the motivations behind four dimensionalism...
Posted by Estella on May 8, 2006, at 6:50:43
In reply to Re: part-whole relations, posted by Estella on May 8, 2006, at 4:03:24
sorry didn't realise you need a subscription to view the oxford online material. crap. sorry bout that :-(
Posted by agent858 on June 4, 2006, at 23:36:31
In reply to Re: part-whole relations, posted by zeugma on May 7, 2006, at 23:16:04
i love you z
i'll miss our conversations
we had some great ones
we did
:-)
i'll never forget them
i'll never forget you
take care
(((((((((z)))))))))))
Posted by zeugma on June 15, 2006, at 20:57:36
In reply to z, posted by agent858 on June 4, 2006, at 23:36:31
> i love you z
> i'll miss our conversations
> we had some great ones
> we did
> :-)
> i'll never forget them
> i'll never forget you
> take care
> (((((((((z)))))))))))>>you too a858
(((((a858))))
it seems like neither of us are here at the same time anymore (are we like clark kent and superman then?)
(((((a858))))
-z
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