Meta Dynamics?
Posted: Fri Dec 05, 2003 10:17 am
Ill venture a partial reply. (Im not prepared to respond to all of the
"windup" to the "pitch," but Ill respond to the "pitch" which I take to be
your question about whether System Dynamics has "anything fundamental or
unique OF ITS OWN to say about the way the universe AS A WHOLE works....")
Yes, I think System Dynamics potentially does have something to say about
how the universe works, but our perspective is far from unique. A major
portion of what System Dynamics has to say comes from our feedback
perspective, and were not alone in that. George Richardsons brilliant
book, "Feedback Thought in Social Science and Systems Theory," does a
terrific job of explicating this.
Also, Im not sure how prepared we are to actually offer as theory the
notion that feedback rules the universe. We certainly have found many, many
examples where this seems to be true, but I know of little foundational work
that would turn our myriad observations (which may be colored by our
tendency to see feedback everywhere -- i.e., by our own biases and cognitive
limitations and errors) into what can be truly called a theory.
It may be, and I tend to think this is the case, that feedback loops are
truly a fundamental characteristic of dynamic behavior at any level of
complexity beyond the extremely simple -- which is to say, of any system
that is interesting enough to warrant study or to be of practical value.
Ill offer another candidate for taking part in the System Dynamics theory
of how the universe works: the extremely powerful claim that one needs only
two kinds of "things" in ones model of a dynamic system (i.e., stocks [or
accumulations] and flows [or rates.]) This is one of those nice, because
unexpected and simplifying, assumptions that good theories seem to consist
of.
Having said this much, I must also say that any of these speculative
candidates for theory must always be put in the context of what chunk of
"the universe" we claim to be able to explain and predict. Just as Newtons
theory of "force" does not intend to explain "the force of your argument" or
how one person can "force" another to do something, so our "theory" has its
limits as well. There are levels of prediction of the behavior of dynamic
systems for which System Dynamics is not well suited, and Im personally
struggling with how we build self-adaptation into our models -- i.e., how we
model what Jay Forrester calls "policy changes" without us (the modeler
builders) stepping in, like a deus ex machina, and changing a rate equation.
And if we dont have a nice way to model self-adapting systems, we wont
have much claim on a theory of how the universe works, in my opinion.
Others have their favorite shortcomings as well.
All of which may mean that what we have is a very useful tool for
understanding (quite a bit but by no means all about) dynamic systems, which
is based on some theories about how the universe works, but does not itself
contribute such a theory.
From: "John Gunkler" <jgunkler@sprintmail.com>
"windup" to the "pitch," but Ill respond to the "pitch" which I take to be
your question about whether System Dynamics has "anything fundamental or
unique OF ITS OWN to say about the way the universe AS A WHOLE works....")
Yes, I think System Dynamics potentially does have something to say about
how the universe works, but our perspective is far from unique. A major
portion of what System Dynamics has to say comes from our feedback
perspective, and were not alone in that. George Richardsons brilliant
book, "Feedback Thought in Social Science and Systems Theory," does a
terrific job of explicating this.
Also, Im not sure how prepared we are to actually offer as theory the
notion that feedback rules the universe. We certainly have found many, many
examples where this seems to be true, but I know of little foundational work
that would turn our myriad observations (which may be colored by our
tendency to see feedback everywhere -- i.e., by our own biases and cognitive
limitations and errors) into what can be truly called a theory.
It may be, and I tend to think this is the case, that feedback loops are
truly a fundamental characteristic of dynamic behavior at any level of
complexity beyond the extremely simple -- which is to say, of any system
that is interesting enough to warrant study or to be of practical value.
Ill offer another candidate for taking part in the System Dynamics theory
of how the universe works: the extremely powerful claim that one needs only
two kinds of "things" in ones model of a dynamic system (i.e., stocks [or
accumulations] and flows [or rates.]) This is one of those nice, because
unexpected and simplifying, assumptions that good theories seem to consist
of.
Having said this much, I must also say that any of these speculative
candidates for theory must always be put in the context of what chunk of
"the universe" we claim to be able to explain and predict. Just as Newtons
theory of "force" does not intend to explain "the force of your argument" or
how one person can "force" another to do something, so our "theory" has its
limits as well. There are levels of prediction of the behavior of dynamic
systems for which System Dynamics is not well suited, and Im personally
struggling with how we build self-adaptation into our models -- i.e., how we
model what Jay Forrester calls "policy changes" without us (the modeler
builders) stepping in, like a deus ex machina, and changing a rate equation.
And if we dont have a nice way to model self-adapting systems, we wont
have much claim on a theory of how the universe works, in my opinion.
Others have their favorite shortcomings as well.
All of which may mean that what we have is a very useful tool for
understanding (quite a bit but by no means all about) dynamic systems, which
is based on some theories about how the universe works, but does not itself
contribute such a theory.
From: "John Gunkler" <jgunkler@sprintmail.com>