[Oops .. reply did not include friam]
On Sep 7, 2009, at 10:03 PM, Nicholas Thompson wrote:
Hi, Owen,
Very interesting. Where does your version of this distinction come
from?
Who has formalized it? I need to know.
Oops, I may have forgotten the wikipedia link:
http://en.wikipedia.org/wiki/Emergence
specifically:
http://en.wikipedia.org/wiki/Emergence#Strong_vs._weak_emergence
Note they quote Bedau.
I've somewhat loosely paraphrased the weak/strong distinction, but it
appears to be within scope. I'd say any features of a time dependent
system that are directly calculable from the initial conditions, once
you know how, are weakly emergent. But features that cannot be
reverse engineered, so to speak, are strong. Thus systems with
chaotic components (Lyapunov exponent > 0) are likely to exhibit
strong emergent features.
-- Owen
I think this version is different from the same distinction in Bedau,
which is in the collection we will begin discussing in the "Seminar"
on
Thursday afternoon (4pm, DS), but frankly I found the Bedau article so
tortured I cannot be sure. Bedau distinguishes three different
"degrees"
of emergence, if you will; nominal, weak, and strong. Something is
nominally emergent if it displays properties that cannot be
displayed by
its parts. At the other extreme is strong emergence which "adds the
requirement that emergent properties are supervenient properties with
irreducible causal powers". Both supervenient and irreducible are
difficult terms. Supervenient implies to me a causal ratchet in which
knowing how the parts are arranged tells you how the whole will
behave but
knowing how the whole is behaving tells you only that the parts are
arranged on one of a potentially infinite set of ways. Irreducible
probably means that the whole can do stuff the parts cant. Neither
term
seem to suggest irreversibility, which is the criterion your guy
suggests.
Weak emergence is said to occur when the only way you can work out
what the
properties of the whole will be is by assembling the parts and
seeing what
happens, as in a simulation. What these two have to do with one
another is
a mystery to me, so if you have an author with a more lucid version
of the
distinction, I am all ears.
Fortunately (or unfortunately) the Bedau article is available on the
web at
http://people.reed.edu/~mab/publications/papers/principia.pdf, so
you can
suffer without buying the book.
Nick
Nicholas S. Thompson
Emeritus Professor of Psychology and Ethology,
Clark University ([email protected])
http://home.earthlink.net/~nickthompson/naturaldesigns/
[Original Message]
From: Owen Densmore <[email protected]>
To: <[email protected]>; The Friday Morning Applied
Complexity
Coffee Group <[email protected]>
Date: 9/7/2009 8:28:41 PM
Subject: Re: [FRIAM] emergence
On Sep 7, 2009, at 6:39 PM, Nicholas Thompson wrote:
Owen,
You wrote:
I think it's simply the appearance within a time varying aggregate
system of a feature not apparently derived from its components'
interactions.
A perfect example of a non-"out there" definition. "Apparently"
implies
that further understanding, information, knowledge will dispel the
emergence. Many smart people hold that position,, but I am not one
of them
(;-})
Well, I was fudging a bit with "apparently". Formal emergence is
divided into two domains, weak and strong. If I understand it
correctly, irreversible phenomena are the strong emergence types,
while reversible are the weak.
In plan language, if the emergence is derived from ignorance, it is
weak. If it is fundamental (chaos, for example), it is strong.
-- Owen
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