Re: [Fis] probability versus power laws

From: Guy A. Hoelzer <[email protected]>
Date: Tue 20 Jul 2004 - 21:26:54 CEST

Commenting on the apparent conflict between the principles of "least
effort" and "least action":

On Jul 20, 2004, at 12:43 AM, Viktoras Didziulis wrote:

> Replying to Stan:
> �
> > I will try to express the idea... Originally Zipf and recently
> >Ramon Ferrer i Cancho, Richard V. Sole (2003) both attribute Zipf's
> law to
> >the principle of "least effort".
> >SS: So, do you mean the physical principle of least action?
> >V.: No. It is from Cybernetics.�The principle of the least�effort
> says: "a system will try to adapt to its environment or will try to
> change the environment to suit its needs, whichever is easier"
> (dictionary of Cybernetics and Systems�at
> http://pespmc1.vub.ac.be/ASC/INDEXASC.html).
> �
> >Now let me translate your question 'how does "data to being plotted
> as a
> >power laws suggest systematicity" ?' to 'how can the principle of the
> >least effort relate with systematicity in terms of structure of a
> system
> >?' Possible answer... Systems evolve or grow,
> >SS: Not by least effort! They strive mightily to grow.
> V.: Let me disagree. Let's compare for example life and an explosion
> of a mixture of hydrogen and oxygen, both from a chemical point of
> view are�oxidation processes. Life is an example
> of�oxidation�processes controlled by a complex well organized system.
> Meanwhile the explosive oxidation of free hydrogen is much more
> mighty...
> �
> >they respond to changes in their environment, they have to optimize
> their
> >structure and performance for optimal functioning (being a structural
> part
> >of other systems), or in other words systems communicate with their
> >environment. Something that is 'not a system' does not 'care' about
> >optimization of it's performance, growth, development, adaptation, or
> any
> >sort of evolution, energy saving (principle of least efforts)
> >SS: I would like to hear this principle stated in words explicitly.
> >In general there is no "energy saving" in natural systems. They
> dissipate
> >energy gradients as fast as possible.
> V.: I would not agree again...�The definition of the principle of
> least effort�and�the�comparison of controlled vs. uncontrolled
> oxidation�look like saying the opposite. The later dissipate energy
> gradients much faster comparing with much more complex living systems.
> One could also think of difference�between�controlled
> nuclear�breakdown in power-stations vs. uncontrolled�blast if to
> remember�our own�creations.�
> �
> >or structural change simply because of the absence of any internal
> >organization or structure or feedback loop between the 'non-system' or
> >'random system' and it's environment. Its history should be uniform:
> no
> >changes in structure, no development, no growth, no evolution, no
> >function, no communication - no need for the least effort... As a
> >consequence a structure of any system facing the entropy should be
> >organized in such a way as to oppose the II-nd law and optimize its
> >performance against energy losses - e.g. the principle of least effort
> >that is true for language also works elsewhere (any other
> communication).
> > SS: I disagree with this supposed "least effort" Least action would
> > have nothing to do with it. It is the smallest integral over
> velocity, mass
> > and path length. From that you cannot derive energy efficiency.
> �V.:�May principles of Cybernetics�be incompatible with�laws of
> Physics or vice versa ?�I�would not like to think this�is
> an�unsolvable "conflict"�between those two domains of science. On the
> other hand I would doubt that physics alone is�capable�or has all
> means to explain what is system, complexity, information,
> communication, life...

I suspect that Stan and Viktoras are looking at systems from different
viewpoints, which is generating the apparent conflict. Stan is
focusing on the striving of self-organization driven by opportunity to
channel flows across gradients, while Viktoras is focusing on the
structural solutions adopted by systems to the challenge of flows. In
this light, I find myself agreeing with both views. Systems do indeed
strive "mightily" to self-organize and break down gradients, but they
do so given the constraints of their circumstances. Flows, and
dynamical systems themselves, are always searching for and pushing up
against sources of resistance. Resistance is either gradually
overcome, or adapted to. Explosions are like potential systems that
tear through frictional resistance as they grow; but failing to sense
and respond to sources of resistance in the process dooms an explosion
to a rapid extinction.

The principle of least effort makes good sense to me because flows
always tend to take the path of least resistance. This makes natural
machines relatively efficient. On the other hand, these same systems
are under constant pressure to serve the thermodynamic imperative
("final cause" sensu Stan) by breaking down external gradients. I see
plenty of room to balance these demands. A system only needs to break
down external gradients fast enough to pay the thermodynamic cost of
its continued existence (maintenance, growth, reproduction, ...). Any
extra gradient-breaking would be thermodynamic "icing on the cake." I
could build a fire tonight, but it won't help with my survival or
functioning one bit. It's like tipping the black jack dealer in a
casino (note that I live in Reno). Systems also only need to be
efficient enough to make sure that the rate of fuel input is adequate
to pay the costs of existence. Excess fuel intake allows a system to
generate internal resistances to flow that can be used for the
extraction of free energy (I am thinking of highly complex biological
organisms here). Even then, however, flows will take the path of least
resistance, given the obstacles erected by the system.

In sum, it seems to me that systems evolve to be as efficient as they
can be, given both external and internal (engineered) sources of
resistance. This is the principle of least effort. At the same time,
the efforts they do make are ultimately aimed at channeling flows
across gradients. This often does not look like effort directed at
achieving an externally driven goal because they are paid for their
efforts in the form of free energy with which they express constrained
striving.

My 2 cents,

Guy

Department of Biology
University of Nevada Reno
Reno, NV 89557

Phone: 775-784-4860
Fax: 775-784-1302
Received on Tue Jul 20 21:29:15 2004

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