Re: the two questions

From: David Cressey <cressey73_at_verizon.net>
Date: Wed, 28 Nov 2007 16:50:53 GMT
Message-ID: <N%g3j.14783$7T.12067_at_trndny09>


"David Cressey" <cressey73_at_verizon.net> wrote in message news:xCe3j.27165$701.4743_at_trndny08...
>
> "Brian Selzer" <brian_at_selzer-software.com> wrote in message
> news:tKd3j.66011$RX.14169_at_newssvr11.news.prodigy.net...
> >
> > "JOG" <jog_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.
> >
> > >> 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.
> > >
> >
> >
>
> Can you tell identical twins apart by examining their DNA?
> Does twinning occur among butterflies?
>
>

So DNA is not good for identity, right? Received on Wed Nov 28 2007 - 17:50:53 CET

Original text of this message