Systems are defined by Karl
Ludwig von Bertalanffy as “sets of elements standing in interrelation”.[1] Acknowledging that the definition may seem
vague, von Bertalanffy argues that when the idea is mathematized using
differential equations, novel properties can be adduced in systems in general and
in more specialized applied situations. Although
von Bertalanffy has quite concrete objects in mind, for instance “a galaxy, a
dog, a cell, and an atom are real
systems” [von Bertalanffy’s emphasis], he also recognized as systems those “conceptual systems such as logic,
mathematics (but e.g. also including music) which essentially are symbolic
constructs; with abstracted systems
(science) as a subclass of the latter, i.e. conceptual systems corresponding
with reality.” [von Bertalanffy’s
emphasis][2] There is, it would seem, an immediate
parallel between von Bertalanffy and Husserl in their recognition that thinking
of parts and whole (Husserl) or elements and systems (von Bertalanffy) can
refer to quite concrete objects as well as more essential rules. It is pretty clear though that whereas
Husserl has more commitments to the ideal over the empirical von Bertalanffy’s
emphasizes the converse.
Hierarchy theory is a component
of this more general systems theory that is applied to understanding the “architecture”
of complex systems.[3] “Nature loves hierarchies”, Herbert Simon,
the social scientists, who pointed out that natural objects can be seen as
arranged like Chinese boxes, each level inside a progressively larger box. Herbert Simon recognizes four intertwining
sequences: chemical, organismic, genetic, and human social organizations.[4] This fourth hierarchy includes “the
“programs” and other components called elementary information processes”.[5] We might like to think of this as “mind”, but
in this fourth hierarchy Simon also includes those programs which “have been
occurring with growing in the artificial complex systems called digital
computers.”
The tenets of hierarchy theory
have been attractive to ecologists since observations of the nestedness of
ecological levels, organisms, populations (of a single species), communities
(of several species), ecosystems (the biotic community combined with the
abiotic environment) and so on. This
hierarchy in natural systems is referred to as the “level of organization”
concept. Ecologists have proceeded with
the assumption that subsystems on the same level can be studied without
reference to one another. For instance,
we might study prairies, making the assumption that we do not simultaneously
have to include tropical rainforests in our investigation.[6] This methodological assumption relies upon
the supposed “near-decomposability” of all medium-number systems and is rooted
in the observation that “most interactions in nature, between systems of all
kind, decrease in strength with distance.”[7]
However, there are some dangers in simply conflating ecological hierarchy with
“levels of organizations” concept since natural systems are comprised of more
than just simple entities (organisms with clearly defined boundaries, biotic
communities that are spatiotemporally reasonably well designed etc.). They are also comprised of more diffusely
defined sets of processes, and, depending upon the research question, there is
more than one “n-1” level that might be examined.[8]
We need not detain ourselves with
details of how ecologists have applied their analyses of wholes and parts to
questions of environmental concern.
Rather, we note, quite briefly, some of the theoretical assumptions and
conclusions derived from their work, especially those aspects that either
parallel or diverge from Husserl’s perspective.
Though some of what follows is the result of empirical generalizations, amenable
to experimental verification, some conclusions, however, are based upon a
mathematical analysis thus having a more abstract status.
Systems can be organized vertically
as we have been doing above – cells, tissues, organs and so forth. Behaviors at increasingly higher levels are
characterized as occurring at slower rates.[9] Tree leaves, for example, have the
physiological mechanisms to respond to momentary changes in atmospheric content
of gases, whereas the entire biosphere responds only to decadal long changes in
atmospheric changes (a root of issues concerning atmospheric carbon dioxide and
climate change). There is a level of
buffering between elements in the vertical hierarchy. This is a consequence of their operation at
distinct rates. If this were not so ever
small oscillation at lower levels could ramify catastrophically throughout the
systems. This places, therefore a
limitation on connectivity within natural systems. This is counterintuitive in ecology where the
connectivity between systems elements had been a default position.[10] In
contrast, the conclusions above point to a “loose vertical coupling” in
ecological systems. As O’Neill and his
colleagues have pointed out: “The old imagery of the natural world as having
everything connected to everything else is shortsighted."[11]
Decomposing systems into parts
and levels by recourse to rate processes is described by O’Neill and colleagues
as more “fundamental” than any other method of identifying systems levels.[12] Alternatives such as basing a hierarchy of
“tangible components” or indeed basing analysis on the traditional levels of organization
are merely a “special case of surfaces defined on differences in rate”. Within
a single level distinct parts can be thought of a loosely coupled but this time
in a “horizontal” sense. Subsystems (Husserl’s parts with parts), often
referred to as “holons” in systems literature, are defined by frequency of
internal interaction frequency.
Interactions between holons are relatively infrequent. Although the boundary of a holon can be
tangible (a cell wall, for example) it does not have to be (a rhizosphere – a
plant root with the small soil volume surrounding it – is a holon but does not
have a visible boundary). Thus a system
with a very large number of potential components (parts of a holon) are
generally organized into a more tractable number of units, interactions among
which define system behavior.
We can mention one final item of
importance in systems theory the implications of which has been discussed
extensively in ecology: the notion of emergence. Briefly, emergence refers to a property of
self-organization in systems whereby large-scale features at one level of the
hierarchy are manifested but are not predicable by inspecting the behavior of
their component parts. Nonetheless, the
emergent features can impose constraints on lower levels in the hierarchy
(downward causation). In ecology
emergence is often summarized by the expression “The whole is greater than the
sum of its parts”. In fact, this was a
frequently employed catchphrase of E P Odum, the influential 20th C
American ecosystem ecologist. In the
fifth and final edition of his influential textbook Fundamentals of Ecology Odum defines emergent property as those
that emerge from components are combined to form larger wholes.[13]
Such properties are, he claimed, “nonreducible”. To illustrate he suggests that
when the components of water of combined its fluid properties are unpredictable
from an inspection of its gaseous components.
We can now summarize that the characteristics
of the theory of wholes and parts in hierarchy theory are that entities are
defined by the rates of processes associated with various parts arranged as
progressively larger wholes in a hierarchical sequence. A consequence of rate defined entification is
1) that parts are only loosely coupled with higher and lower levels in a
hierarchy and 2) that holons are loosely coupled horizontally with other
holons. A third component, emergence,
has been incorporated into systems analysis in computer science, psychology,
ecology, and even into the traditional physical sciences.
The view of parts and wholes
emerging in systems theory has quite clearly got parallels in Husserl’s
account. I will have to defer a full
treatment of these parallels for another time and remain satisfied that by
lining these two accounts up side-by-side that I have at least provided an
entry-point into a larger discussion. It
is apparent that hierarchy theory is concerned especially with an analysis of
concrete objects and with the way in which they may be (psychologically) encountered
by a scientist. This corresponds
somewhat with Chapter 1 of Logical
Investigation III The difference
between independent and non-independent objects, even if there remain
striking differences in the specifics of the analysis. However, it is also apparent that there is no
development in hierarchy theory that concern itself in an analysis of
Ideals. It is the tracking back of the
concrete analysis into a priori
relations that makes Husserl’s account especially provocative. Even if we must leave such a comparison of
Husserl’s theory and hierarchy theory aside for now, I will say briefly say something
about the third aspect of hierarchy theory – emergence – in relation to Husserl’s
work.
[1] von Bertalanffy, Karl Ludwig
(1968) General System theory: Foundations, Development, Applications, New York:
George Braziller, revised edition 1976 p38
[2] Ibid, xxvi
[3] Simon, Herbert A. (1973) The Organization of Complex Systems in Hierarchy Theory: The Challenge of Complex
Systems (The International Library of Systems Theory and Philosophy),
editor H H Pattee, p5
[4] Ibid,
[5] Ibid., 6
[6] O'Neill, R. V., D. DeAngelis, J.
Waide and T. F. H. Allen. (1986) A Hierarchical Concept of Ecosystems.
Princeton University Press.
[7] Simon, 9
[8] In the ecological hierarchy
literature the fairly reasonable approach of calling the level of proximate
interest in a given system “n”, the level below it is then n-1, the level about
n+1 etc. Most ecologists restrict
themselves to a “triad” of n-1, n, n+1.
Explanations of behavior are typically sought in the n-1 level (and
though one might reduce the system future it is usually deemed not useful to do
so) and the systems constraints are located at the n+1 level.
[9] O’Neill et al, 76
[10] A popular expression of this
sentiment is from John Muir, who in My First Summer in the Sierra (1911) wrote
“When we try to pick out anything by itself, we find it hitched to everything
else in the Universe.”
[11] O’Neill et al, 86
[12] Ibid., 93
[13] Odum Eugene and Barrett Gary W.
Fundamentals of Ecology Brooks Cole; 5 edition (July 27, 2004)
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