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From page 11 of Anticipatory Systems:
(Robert Rosen):
"The universality of the reactive paradigm is not very
different from the universality of the epicycles. Both modes of universality
ultimately arise from the mathematical fact that any function can be
approximated arbitrarily closely by functions canonically constructed out of a
suitably chosen 'basis set' whose members have a special form. [snip; mathematical illustrations] From this it
follows that if any kind of system behavior can be described in functional terms
[in the mathematical sense, not the biological sense, of
function] it can also be generated by a suitably
constructed combination of systems which generate the elements of a basis set,
and this entirely within a reactive mode. But it is clear that there is nothing
unique about a system so constructed; we can do the same with any basis set. All
these systems are different from one another, and may be likewise different from
the initial system whose behavior we wanted to describe. It is in this sense
that we can only speak of simulation, and not of explanation, of our system's
behavior in these terms.
Nevertheless, I believe that it is precisely the universality
of the reactive paradigm which has played the crucial role in concealing the
inadequacy of the paradigm for dealing with anticipatory systems.
Indeed, it is clear that if we are confronted with a system
which contains a predictive model, and which uses the predictions of that model
to generate its behavior, we cannot claim to understand the behavior unless the
model itself is taken into account. Moreover, if we wish to construct such a
system, we cannot do so entirely within the framework appropriate to the
synthesis of purely reactive systems.
On these grounds, I was thus led to the conclusion that an
entirely new approach was needed, in which the capability for anticipatory
behavior was present from the outset. Such an approach would necessarily
include, as its most important component, a comprehensive theory of models and
of modeling. The purpose of the present volume in fact, is to develop the
principles of such an approach, and to describe its relation to other realms of
mathematical and scientific investigation. With these and similar considerations
in mind, I proceeded to prepare a number of working papers on anticipatory
behavior, and the relation of this kind of behavior to the formulation and
implementation of policy. Some of these papers were later published in the
"International Journal of General Systems". The first one I prepared was
entitled, "Planning, management, policies, and strategies: Four fuzzy concepts",
and it already contained the seeds of the entire approach I developed to deal
with these matters. For this reason, and to indicate the context in which I was
working at the Center, it may be helpful to cite some of the original
material directly. The introductory section began as follows:
"It is fair to say that the mood of those concerned with
the problems of contemporary society is apocalyptic. It is widely felt that our
social structure is in the midst of crises, certainly serious, and perhaps
ultimate. It is further widely felt that the social crises we perceive have
arisen primarily because of the anarchic, laissez-faire attitude taken in the
past towards science, technology, economics, and politics. The viewpoint of most
of those who have written on these subjects revolves around the theme that if we
allow these anarchies to continue we are lost; indeed, on way to make a name
nowadays is to prove, preferably with computer models, that an extrapolation of
present practices will lead to imminent cataclysm. The alternative to anarchy is
management; and management implies un turn the systematic implementation of
specific plans, programs, policies and strategies. Thus it is no wonder that the
circle of ideas centering around the concept of planning plays a dominant role
in current thought.
However it seems that the net effect of the current
emphasis on planning has been simply to shift the anarchy we perceive in our
social processes into our ideas about the management of these processes. If we
consider, for example, the area of "economic development" of the underdeveloped
countries (a topic which has been extensively considered by many august bodies),
we find (a) that there is no clear idea of what constitutes "development"; (b)
that the various definitions employed by those concerned with development are
incompatible and contradictory; (c) that even among those who happen to share
the same views as to the ands of development, there are similarly incompatible
and contradictory views as to the means whereby the end can be attained. Yet in
the name of developmental planning, an enormous amount of time, ink, money, and
even blood is in the process of being spilled. Surely no remedy can be expected
if the cure and the disease are indistinguishable.
If it is the case that planning is as anarchic as the
social developments it is intended to control, then we must ask whether there
is, in some sense, a "plan for planning" or whether we face an infinite and
futile anarchic regress. It may seem at firs sight that by putting a question in
this form we gain nothing. However, what we shall attempt to argue in the
present paper is that, in fact, this kind of question is "well-posed" in a
scientific sense: that it can be investigated in a rigorous fashion and its
consequences explored. Moreover, we would like to argue that, in the process of
investigating this question, some useful and potentially applicable insights
into planning itself are obtainable.
[snip: lengthy discussion of how to structure a planning process]
The enumeration above seems to be a useful atomization of
the planning process for the class of systems we have constructed. Within this
class, then, we can proceed further and examine some of the consequences of
planning, and in particular the ways in which planning can go wrong.
The notion of how planning could go wrong was of course of
primary interest to the Center; indeed, for months I had heard a succession of
discouraging papers dealing with little else. It seemed to me that by
elaborating on this theme I could establish a direct contact between my
ruminations and the Center's preoccupations. My preliminary discussion of these
matters ended as follows:
We would like to conjecture further that, for any specific
planning situation, each of the ways in which planning can go wrong will lead to
a particular kind of syndrome in the total system (just as the defect of any
part of a sensory mechanism in an organism leads to a particular array of
symptoms). It should therefore be possible, in principle, to develop a definite
diagnostic procedure to "trouble-shoot" a system of this kind, by mimicking the
procedures used in neurology and psychology. Indeed, it is amusing to think that
such planning systems are capable of exhibiting syndromes (e.g. of "neuroses")
very much like and indeed analogous to those manifested by individual
organisms.
Such considerations as these led naturally to the general
problems connected with system error, malfunction or breakdown, which have
always been hard to formulate, and are still poorly understood. Closest to the
surface in this direction, especially in the human realm, were breakdowns
arising from the incorporation of incorrect elements into the diagram shown
above.... faulty models, inappropriate choice of effectors, etc. I soon
realized, however, that there was a more profound aspect of system breakdown,
arising from the basic nature of the modeling process itself, and from the
character of the system interactions required in the very act of imposing
controls. These were initially considered under the heading of "side effects",
borrowing a medical terminology describing unavoidable and usually unfortunate
consequences of employing therapeutic agents (an area which of course represents
yet another branch of control therapy). As I used the term, I meant it to
connote unplanned and unforeseeable consequences on system behavior arising from
the implementation of controls designed to accomplish other purposes; or, in a
related context, the appearance of unpredicted behavior in a system build in
accordance with a particular plan or blueprint. Thus the question was posed: are
such side effects a necessary consequence of all control? Or is there room for
hope that, with sufficient cleverness, the ideal of the "magic bullet", the
miraculous cure which specifically restores health with no other effect, can
actually be attained?
Since this notion of side effects is so important, let us
consider some examples. Of the medical realm we need not speak extensively,
except to note that almost every therapeutic agent, as well as most diagnostic
agents, create them/ sometimes spectacularly so, as in the thalidomide scandal
of some years past. We are also familiar with ecological examples, in which man
has unwittingly upset "the balance of nature" through injudicious introduction
or elimination of species in a particular habitat; well known instances of this
are the introduction of rabbits to Australia, to give the gentlemen farmers
something to hunt on the weekend; or the importation of the mongoose into Santo
Domingo, in the belief that because the mongoose kills cobras it would also
eliminate local poisonous snakes such as the fer-de-lance. Examples from
technology also abound; for instance we may cite the presence of unsuspected
oscillatory modes in the Tacoma Bay Bridge, which ultimately caused it to
collapse in a high wind; or the Ohio Turnpike, which was built without curves on
the theory that curves are where accidents occur; this led to the discovery of
road hypnosis. Norbert Weiner warned darkly of the possibility of similar
disastrous side effects in connection with the perils of relying on computers to
implement policy. He analogized this situation to an invocation of magical aids
as related in innumerable legends and folk tales; specifically, such stories as
"The Sorcerer's Apprentice", "The Mill Which Ground Nothing but Salt", "The
Monkey's Paw", and "The Midas Touch". And of course, many of the social and
economic panaceas introduced in the past decades have not only generated such
unfortunate side effects, but have in the long run served to exacerbate the very
problems they were intended to control.
The ubiquity of these examples and the dearth of counter
examples suggests that there is indeed something universal about such behavior
and that it might be important to discover what it is.
My first clumsy attempts to come to grips with this underlying
principle, at this early stage, were as follows:
There is, however, a class of planning difficulties which
do not arise from such obvious considerations and which merit a fuller
discussion. This class of difficulties has to do with the problem of side
effects; as we shall see, these will generally arise, even if the models system
is perfect and the effectors perfectly designed and programmed, because of
inherent system-theoretic properties. Let us see how this comes about.
In a previous paper we enunciated a conjecture which I
believe to have general validity: namely; that in carrying out any particular
functional activity, a system S typically only uses a few of its degrees of
freedom. This proposition has several crucial corollaries, of which we noted two
the preceding paper:
(1) The same structure can be involved simultaneously in
many different functional activities, and conversely.
(2) The same functional activity can be carried out (or
realized) by many different kinds of structures.
We stressed in that paper how the fact that all of
the state variables defining any particular system S are more or less strongly
linked to one another via the equations of motion of the system, taken together
with the fact that the many state variables not involved in a particular
functional activity were free to interact with other systems in a non-functional
or dysfunctional way, implied that any particular functional activity tends to
be modified or lost over timer. This, we feel, is a most important result, which
bears directly on the "planning" process under discussion. The easiest way to
see this is to draw another corollary from the fundamental proposition that only
a few degrees of freedom of a system S are involved in any particular functional
activity of S.
(#) Any functional activity of a system S can be modeled
by a system whose structure is simple compared to that of S (simply by
neglecting the non-functional degrees of freedom of S). Indeed, it is largely
because of this property that science is possible at all.
Conversely,
(4) No one model is capable of capturing the full
potentialities of a system S for interactions with arbitrary
systems.
The corollary (4) is true even of the best models, and it
is this corollary which bears most directly on the problem of side effects. Let
us recall that S is by hypothesis a real system, whereas M is only a model of a
particular functional activity of S. There are thus many degrees of freedom of S
which are not modeled in M. Even if M is a good model, then, the capability for
dealing with the non-functional degrees of freedom in S have necessarily been
abstracted away. And these degrees of freedom, which continue to exist in S, are
generally linked to the degrees of freedom of S which are modeled in M, through
the overall equations of motion which govern S.
Now the planning process requires us to construct a real
system E, which is to interact with S through a particular subset of the degrees
of freedom of S (indeed, though a subset of those degrees of freedom of S which
are modeled in M). But from our general proposition, only a few of the degrees
of freedom of E can be involved in this interaction. Thus both E and S have in
general many "non-functional" degrees of freedom, through which other,
non-modeled interactions can take place. Because of the linkage of all
observables, the actual interaction between E and S specified in the planning
process will in general be affected. Therefore, we find that the two following
propositions are generally true: (a) An effector system E will in general
have other effects on an object system S than those which are planned; (b) The
planned modes of interaction between E and S will be modified by these
effects. Both of these propositions describe the kind of thing we usually
refer to as side effects. As we see, such side effects are unavoidable
consequences of the general properties of systems and their interaction. They
are by nature unpredictable, and are inherent in the planning process no matter
how well that process is technically carried out. As we pointed out in our
previous paper, there are a number of ways around this kind of difficulty, which
we have partially characterized, but they are only applicable in special
circumstances.
The basic principle struggling to emerge here is the
following: The ultimate seat of the side effects arising in anticipatory
control, and indeed of the entire concept of error or malfunction in system
theory as a whole, rests on the discrepancy between the behavior actually
exhibited by a natural system, and the corresponding behavior predicted on the
basis of a model of that system. For a model is necessarily an abstraction, in
that degrees of freedom which are present in the system are absent in the model.
In physical terms, the system is open to interactions through these degrees of
freedom, while the model is necessarily closed to such interactions; the
discrepancy between system behavior and model behavior is thus a
manifestation of the difference between a closed system and an open one. This is
one of the basic themes which we shall develop in detail in the subsequent
chapters.
My initial paper on anticipatory systems concluded with
several observations, which I hoped would be suggestive to my audience. The
first was the following: that it was unlikely that side effects could be removed
by simply augmenting the underlying model, or by attempting to control each side
effect separately as it appeared. The reason for this is that both of these
strategies face an incipient infinite regress, similar to that pointed out by
Gödel in his demonstration of the existence of unprovable propositions within
any consistent and sufficiently rich system of axioms. Oddly enough, the
possibility of avoiding this infinite regress was not entirely foreclosed; this
followed in a surprising way from some of my earliest work on in relational
biology, which was mentioned earlier:
There are many ramifications of the class of systems
developed above, for the purpose of studying the planning process, which deserve
somewhat fuller consideration than we have allowed. In this section we shall
consider two of them: (a) how can we update and improve the model system M, and
the effector system E, on the basis of information about the behavior of S
itself and (b) how can we avoid a number of apparent infinite regresses which
seem to be inherent in the planning process?
These two apparently separate questions are actually forms
of the same question. We can see this as follows. If we are going to improve,
say, the model system M, then we must do so by means of a set of effectors E' .
These effectors E' must be controlled by information pertaining to the effect of
M on S; i.e. by a model system M' of the system (S+M+E). in other words, we must
construct for the purpose of updating and improving M a system which looks
exactly like it except that we replace M by M', E by E', and S by S+M+E. But
then we may ask how we can update M' ; in this way we see an incipient infinite
regress.
There is another infinite regress inherent in the
discussion given of side effects in the preceding section. We have seen that the
interaction of the effectors E with the object system S typically give rise to
effects in S unpredictable in principle from the model system M. However, these
effects too, by the basic principle that only a few degrees of freedom of S and
E are utilized in such interactions, are capable of being modeled. That is, we
can in principle construct a new model system M1 of the interaction
between S and E, which describes interactions not describable in M. If these
interactions are unfavorable, we can construct a new set of effectors, say E1,
which will steer the system S away from those side effects. But just as with E,
the system S will typically interact with E1 in ways which are in principle not
comprehensible within the models M or M1; these will require another model M2
and corresponding new effectors E2. In this way we see another incipient
infinite regress forming. Indeed, this last infinite regress is highly
reminiscent of the "technological imperative" which we were warned against by
Ellul and many others. Thus the question arises; can such infinite regresses be
avoided?
These kinds of questions are well-posed, and can be
investigated in system theoretic terms. We have considered questions like these
in a very different connection; namely, under what circumstances is it possible
to add a new functional activity to a biological organization like a cell? It
turns out that one cannot simply add an arbitrary function and still preserve
the organization; we must typically keep adding functions without limit. But
under certain circumstances, the process does indeed terminate; the new function
is included (though not just the new function in general) and the overall
organization is manifested in the enlarged system. On the basis of these
considerations, I would conjecture that (a) it is possible in principle to avoid
the infinite regresses, and in particular to find ways of updating the model M
and the effectors E' (b) not every way of initiating and implementing a planning
process allows us to avoid the infinite regress. The first conjecture is
optimistic; there are ways of avoiding this form of the "technological
imperative". The second can be quite pessimistic in reference to our actual
society. For if we have in fact embarked on a path for which the infinite
regresses cannot be avoided, then we are in serious trouble. Avoiding the
infinite regresses means that the developmental processes will stop, and that a
stable steady-state condition can be reached. Once embarked on a path for which
the infinite regresses cannot be avoided, no stable steady-state condition is
possible. I do not know which is the case in our own present circumstances, but
it should at least be possible to find out.
I hope that the above few remarks on the planning process
will provide food for thought for those more competent to investigate such
problems than I am.
The theoretical principle underlying this analysis of failure
in anticipatory control systems is not wholly negative. In fact, we shall argue
later that it also underlies the phenomena of emergence which characterize
evolutionary and developmental processes in biology. It may be helpful to cite
one more excerpt of a paper originally prepared for the Center Dialog, which
dealt with this aspect:
It may perhaps be worth noting at this point that the
above phenomenon is responsible for many of the evolutionary properties
exhibited by organisms, and many of the developmental characteristics of social
organizations.
[This is where the excerpt I posted the other day is beginning so I will
include just enough of the other one to wrap up this part...]
Thus the basic problem of avoiding infinite regresses in
anticipatory control systems could be reformulated as follows: can we design
systems which are proof against a Principle of Function
Change?
This was the circle of ideas which I was led to place on
the table at the Center."
I will take a look for something along the lines of John M's request,
although those who have a copy of this book are invited to do the same.
Anticipatory Systems was and still is a revolutionary little book, which was
never really understood enough, in my view, to make it as infamous as it would
otherwise have been in science. I used to worry that my father would become the
target of someone like the Unabomber, a Luddite who hated science and technology
and was willing to kill to stop forward progress. I think the internet may have
accomplished that, if it had existed to the degree it does now, in the 1970's
and 1980's.
Judith
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