----- Original Message -----From: [hidden email]To: [hidden email];[hidden email]Cc: [hidden email]Sent: 6/12/2009 12:33:26 AMSubject: Re: [FRIAM] quick questionHi Nick,
See below.
-- Russ
On Thu, Jun 11, 2009 at 9:48 PM, Nicholas Thompson <[hidden email]> wrote:
Russell,
So, is it Bedau and Philllips you have at hand? I am hoping to get some of
my colleagues in Santa Fe to read that with me next fall.
If that is the source you are using, I also had Bedau's contribution to
this volume in mind when I made the comment below.
I am going to key in some short passages below so we can go over them
together.
He writes that [strong] emergent properties are supervenient properties
with irreducible causal powers"...some of which are "macro-to-micro"
effects[,] termed "downward causation".
Supervenience means, as i understand it, that while each member of some
enumerable list of microstates is sufficient for the occurence of the
emergent macrostate, no one of those states is necessary for its occurence.
So in practice one can have many different micro states that can bring
about the macrostate, but no change in the macrostate without some change
in a microstate.
The necessary and sufficient part isn't part of the definition of "supervenient." The definition is simply your last clause: no change in the macrostate without some change in a microstate.
Downward causation means, as I understand it, that some macrostates are
sufficient for some microstates. This brings about the loopiness that some
of the authors in the book regard as inspired and others regard as vicious.
[Some will argue that if a microstate is sufficient for A macrostate and
that macrostate is sufficient for a microstate then the macrostate drops
out of the equasion and we need simply point out that the first microstate
is sufficient for the second. }
Bedau then writes: "Such [macro] causal powers cannot be explained in
terms of the aggregationof the micro-level potentialities; they are
primtive or "brute" natural powers that arise inexplilcably withthe
existence of certain macro-level entitites."
Which led to my comment that they are, by definition, inexplicable.
I understand downward causation to refer to a new causal power. An example might be dark energy. It causes changes in the universe even though there are no micro explanations for it. If it operates only at cosmological scales (and not just because it is weak at other scales, but it simply doesn't exist at other scales) then it exhibits downward causation. Another example is vitalism, were it true. It would say that there are new causal powers at the biological level that simply come into existence at that level and are not explicable in terms of lower level forces.
Bedau goes on to write, "All the evidence today suggests that strong
emergence is scientifically irrelevant." and goes on to argue that no
essentially examples exist. In othere words, strong emergence is possible,
it just has never been observed. This seems a very strange resolution of
the argument, since it seems to define emergence in terms of our inablity
to explain something, rather than in terms of some measurable property of
the thing itself. This seems very close to the "surprise" argument that
Bedau rejects in the early pages of the same article.
His argument is really a rejection of vitalism. No one wants to be a defender of vitalism, which is the rejected poster boy of downward causation.
I've never seen anyone talk about dark energy in this context. It might be a more respectable candidate for downward causation. But it's not likely -- in my opinion. It's conceivable that dark energy is a new force of nature and that it's different from the other known forces -- gravity, electromagnetic, strong, and weak.But even if that were the case, if it could be shown to exist at all scales -- or perhaps like time and gravity -- to be simply a part of the structure of the universe, it wouldn't qualify as downward causation. Downward causation requires that the new force pop into existence when and only when some macro condition holds but not as a consequence of the micro conditions that make it up.
More on this tomorrow, I hope.
Nick
Nicholas S. Thompson
Emeritus Professor of Psychology and Ethology,
Clark University ([hidden email])
http://home.earthlink.net/~nickthompson/naturaldesigns/
> [Original Message]
> From: russell standish <[hidden email]>
> To: <[hidden email]>; The Friday Morning Applied Complexity
Coffee Group <[hidden email]>would say
> Date: 6/12/2009 3:17:44 PM
> Subject: Re: [FRIAM] quick question
>
> On Thu, Jun 11, 2009 at 07:01:38PM -0600, Nicholas Thompson wrote:
> > Steve,
> >
> > My understanding of the meaning of "strong" emergence is "inexplicable
> > emergence".
> >
> > Is there another meaning?
> >
> > N
>
> Bedau defines it as emergence with downward causation. For example, we----------------------------------------------------------------------------
> that consciousness is strongly emergent if we felt that we could
> consciously influence the activities of our neurons, rather than
> simply our consciousness simply being the result of neuronal activity.
>
> I'm not sure this notion has any use in discussions other than
> consciousness, and even there the notion of epiphenomenalism would say
> that it is void concept.
>
> Cheers
>
> --
>
>
> Prof Russell Standish Phone 0425 253119 (mobile)
> Mathematics
> UNSW SYDNEY 2052 [hidden email]
> Australia http://www.hpcoders.com.au
>
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