Re: the two questions

From: Brian Selzer <brian_at_selzer-software.com>
Date: Fri, 30 Nov 2007 15:46:51 GMT
Message-ID: <LfW3j.25121$JD.17222@newssvr21.news.prodigy.net>

"JOG" <jog_at_cs.nott.ac.uk> wrote in message news:55517bf1-c48a-4bdf-9e84-6d72f81aca83_at_y43g2000hsy.googlegroups.com...

> On Nov 28, 1:07 pm, "Brian Selzer" <br..._at_selzer-software.com> wrote:

>> "JOG" <j..._at_cs.nott.ac.uk> wrote in message
>>
>> news:0c832d02-88f5-495c-ab2b-8098afcd8818_at_d21g2000prf.googlegroups.com...
>>
>>
>>
>> > On Nov 27, 3:49 pm, "Brian Selzer" <br..._at_selzer-software.com> wrote:
>> >> "JOG" <j..._at_cs.nott.ac.uk> wrote in message
>> >> Each individual that existed, exists, or can exist has a property that
>> >> distinguishes it from all other individuals that existed, exist or can
>> >> exist; so, yes, there is a property that the caterpillar and butterfly
>> >> share.
>>
>> > Great, we have agreement :)
>>
>> >> The problem is: I don't think haecceity can be observed directly.
>>
>> > This time I agree with you (although I did have to look up what
>> > 'haeccity' meant) - it is often the case that the identifier we need
>> > isn't available to us (I mean we can't often check a butterflies dna
>> > right...).
>>
>> > But we have to find a solution to this in the real world right - If I
>> > have a butterfly, how do I know it came from the caterpillar from
>> > earlier? Would you agree there are two options?
>>
>> > 1) Check an identifier that we can manage to observe (dna if we're
>> > lucky, more likely the jar number we've kept it in, etc.)
>> > 2) If we couldn't access that identifier (or it was just too much of a
>> > pain to do so), we'd have needed to invent a new identifier as a
>> > replacement, that was trackable (a representative identifer for the
>> > insect's 'haeccity' - similar to what biologists do when they 'tag'
>> > birds).
>>
>> > Again, all in the real world, before we get to a database.
>>
>> There is a third option: continuous observation. If you never take eyes
>> (or
>> the camera) off of the individual, there is no need to reidentify it, and
>> therefore no need for a constant identifier.

>
> How would you know that the insect your looking at now is the same one
> as a second ago? You've tracked its (x,y,z) position. You've just been
> continually checking another of its identifiers! And then you describe
> the butterfly to someone else (after all this is shared data we're
> talking about), and you refer to it as the butterfly you've been
> watching, or the one on camera 2. More identifiers! 'Brian's'
> butterfly or 'Camera 1' butterfly. In fact surrogates for the
> butterfly's locational path!
>

Yet the (x,y,z) position may have changed from a second ago. Clearly it is possible for all observable identifiers for an individual to change from one point in time to another. What is different in this case is that since it is being watched, both the old (x,y,z) and the new (x,y,z) positions are known, and the comparison can be made.

Spatiotemporal location can only be used to permanently identify individuals that have already come into existence. For those that haven't yet, it is not a rigid definite description and thus not a permanent identifier. Although this doesn't appear to apply in this case since if the butterfly exists, then the caterpillar must have already also existed, it is problematic from the standpoint of determining what is possible. For example, it is possible for there to be a new blue caterpillar at point (1,2,3) at noon today, and it is also possible for there to be a new red caterpillar at point (1,2,3) at noon today; but it is not possible for there to be both a new blue and a new red caterpillar at point (1,2,3) at noon today. So point (1,2,3) at noon today has multiple possible interpretations. It may seem like splitting hairs, but I think that there should be a different identifier for the possible blue and the possible red caterpillars since they are obviously different possible organisms. If point (1,2,3) at noon is used to identifiy both possibilities, then that could introduce ambiguity into the determination as to whether one of the two possibilities can become actual.

>>
>> >> If one were able to examine the history of the butterfly, one should
>> >> be
>> >> able
>> >> to determine that it coincides with the history of the caterpillar--up
>> >> to
>> >> the point of the initial snapshot. The problem is: I don't think
>> >> history
>> >> can appear in a snapshot.
>>
>> > I get your gist here but hope we can come back to it after you've
>> > looked at the above question. Regards, J.
> Received on Fri Nov 30 2007 - 09:46:51 CST