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Unit 2. General Systems Theory (GST)
31
10. Can/Must a system’s behavior always be decomposed into independ-
ent parts?
SPECIALIST READING
TEXT A
BASICS OF GENERAL SYSTEMS THEORY
13. Read the text and decide whether the following subjects are
discussed in the text.
• Systems theory’s practical applications.
• Hallmarks of GST.
• Ancient roots of GST.
• Chaos Theory.
General systems theory is a scientific effort to identify structural, behavioral and developmental features common to particular classes of living organisms.
Each body of theory has its implied assumptions or axioms which in reality are impossible to prove and hence must be accepted as value judgments. In
GST one of the basic assumptions embraces the concept of order – an expression
of man’s general need for imaging his world as an ordered cosmos within an
unordered chaos. A consequence implicit in this order is the presumed existence
of a low of lows which in turn inspired the name of the theory. The systematic
search of this low is a main task for GST. Another fundamental assertion is that
traditional science is unable to solve any real world problems because its approach is too often narrow and inclined toward abstract. Systems science in contrast is concerned with the concrete embodiment of the order and lows which are
uncovered.
Kenneth Boulding (1964) formulated five postulates which must be regarded as the starting point for the development of the modern GST. They may
be summarized as follows.
1. Order, regularity and non-randomness are preferable to lack of order or
to irregularity (chaos) and to randomness.
2. Orderliness in the empirical world makes the world good, interesting
and attractive to the systems theorist.
System analyses and control
32
3. There is order in the orderliness of the external or empirical world (order
to the second degree) – a low about lows.
4. To establish order quantification and mathematization are highly valu-
able aids.
5. The search for order and low necessarily involves the quest for those
realities that embody these abstract lows and order – their empirical referents.
Other well-known basic assumptions regarding GST as a philosophy of
world and life have been summarized by Downing Bowler (1981). A selection is
given below.
− The Universe is hierarchy of systems; that is, simple systems are syn-
thesized into more complex systems from subatomic particles to civilizations.
− All systems, or forms of organization, have some characteristics in com-
mon, and it is assumed that statements concerning these characteristics are universally applicable generalizations.
− All levels of systems have novel characteristics that apply universally
upward in the hierarchy to more complex levels but not downward to simpler
levels.
− It is possible to identify relational universals that are applicable to all
systems at all levels of existence.
− Every system has a set of boundaries that indicates some degree of dif-
ferentiation between what is included and excluded in the system.
− Everything that exists, whether formal, existential, or psychological, is
an organized system of energy, matter, and information.
− The Universe consists of processes synthesizing systems of systems and
disintegrating systems of systems. It will continue in its present form as long as
one set of processes doesn’t eliminate the other.
A short summary of Bowler’s assumptions could be expressed in the state-
ment that the design of the macrocosm reflects the structure of the microcosm.
A further perspective on systems has been provided by West Churchman
(1971). According to him, the characteristics of a system are the following:
− It is teleological (purposeful).
− Its performance can be determined.
− It has a user or users.
− It has parts (components) that in and of themselves have purpose.
− It is embedded in an environment.
Unit 2. General Systems Theory (GST)
33
− It includes a decision maker who is internal to the system and who can
change the performance of the parts.
− There is a designer who is concerned with the structure of the system
and whose conceptualization of the system can direct the actions of the decision
maker and ultimately affect the end result of the actions of the entire system.
− The designer’s purpose is to change a system so as to maximize its value
to the user.
− The designer ensures that the system is stable to the extent that he or she
knows its structure and function.
Ludvig von Bertalanffy (1955), Joseph Litterer (1969) and other distinguished persons of the systems movement have formulated the hallmarks of
GST. The list below sums up their efforts.
− Interrelationship and interdependence of objects and their attributes; un-
related and independent elements can never constitute a system.
− Holism: holistic properties not possible to detect by analyses should be
possible to define in the system.
− Goal seeking: systemic interaction must result in some goal or final state
to be reached or some equilibrium point being approached.
− Transformation process: all systems, if they are to attain their goal, must
transform inputs into outputs. In living systems this transformation is mainly of
a cyclical nature.
− Inputs and outputs: in a closed system the inputs are determined once and
for all; in an open system additional inputs are admitted from its environment.
− Entropy: this is the amount of disorder or randomness present at any
system.
− Regulation: the interrelated objects constituting the system must be reg-
ulated in some fashion so as its goals can be realized. Regulation implies that
necessary deviations will be detected and corrected. Feedback is therefore a requisite of effective control. Typical of surviving open systems is a stable state of
dynamic equilibrium.
− Hierarchy: systems are generally complex wholes made up of smaller
subsystems. This nesting of systems within other systems is what is implied by
hierarchy.
− Differentiation: in complex systems, specialized units perform special-
ized functions. This is a characteristic of all complex systems and may also be
called specialization or division of labour.
System analyses and control
34
− Equifinality and multifinality: open systems have equally valid alterna-
tive ways of attaining the same objectives from different initial conditions (convergence) or, from a given initial state, obtain different, and mutually exclusive,
objectives (divergence).
General Systems Theory aims at seeking principles common to systems
in general that may allow scientists and researchers to think more clearly about
the goals of any possible system and about the methods for reaching them [2].
VOCABULARY IN USE
14. Refer back to the text and match the following word combinations.
1. identify
2. solve
3. formulate
4. change
5. affect
6. constitute
7. transform
8. attain
9. establish
a. the end result
b. objectives
c. problems
d. postulates
e. inputs
f. a system
g. order
h. the performance
i. features
15. Fill in the blanks with the word combinations from 14.
1. General systems theory is a scientific effort to _____ common to partic-
ular classes of living organisms.
2. Traditional science is unable to _____ any real world _____.
3. Kenneth Boulding _____ five _____ which must be regarded as the
starting point for the development of the modern GST.
4. A decision maker can _____ of the parts.
5. A designer can _____ of the actions of the entire system.
6. Unrelated and independent elements can never _____.
7. All systems, if they are to attain their goal, must _____ into outputs.
8. Open systems can _____ the same _____ from different initial condi-
tions by equally valid alternative ways.
9. To _____ quantification and mathematization are highly valuable aids.
16. Replace the italicized words with the equivalents from the box.
novel, prove, basic, affect, embodies
Unit 2. General Systems Theory (GST)
35
1. In GST one of the fundamental assumptions embraces the concept of
order
2. All levels of systems have new characteristics that apply universally up-
ward in the hierarchy to more complex levels.
3. Each body of theory has its implied assumptions or axioms which in
reality are impossible to confirm.
4. The search for order and low necessarily involves the quest for those
realities that incorporate these abstract lows and order.
5. There is a designer whose conceptualization of the system can influence
the end result of the actions of the entire system.
COMPREHENSION CHECK
17. Decide whether the following statements are true or false (T/F) by
referring to the information in the text. Then make the necessary changes
so that the false statements become true.
1. In GST one of the basic assumptions embraces the concept of order.
2. Traditional science is able to solve any real world problem.
3. All levels of systems have novel characteristics that apply universally
upward in the hierarchy to more complex levels.
4. It is impossible to identify relational universals that are applicable to all
systems at all levels of existence.
5. A system has components that don’t have any purpose.
6. A decision maker is internal to the system and can change the perfor-
mance of the parts.
7. The designer’s purpose is to change a system so as to minimize its value
to the user.
8. Unrelated and independent elements can constitute a system.
9. All systems, if they are to attain their goal, must transform inputs into
outputs.
10. In a closed system additional inputs are admitted from its environment.
11. General Systems Theory aims at seeking principles common to systems
in general.
18. Answer the questions.
1. What is a main task for GST?
2. Why is the traditional science unable to solve any real world problems?
System analyses and control
36
3. What is systems science concerned with?
4. What is the Universe?
5. Is it possible to identify relational universals that are applicable to all
systems at all levels of existence?
6. What do system boundaries indicate?
7. What does the designer do? What is his purpose?
8. What is entropy?
9. What is Equifinality? multifinality?
10. What does General Systems Theory aim at?
SPECIALIST READING
TEXT B
SYSTEMS THINKING
19. Read the text, make up a plan of the main content and write out
key words for every point of your plan.
points
key words
One of the major breakthroughs in understanding the complex world is
the field of systems theory. The application of this theory is called systems analysis. One of the major tools of systems analysis is systems thinking.
The approach of systems thinking is fundamentally different from that of
traditional forms of analysis. Traditional analysis focuses on the separating the
individual pieces of what is being studied. Systems thinking, in contrast, focuses
on how the thing being studied interacts with the other constituents of the system
of which it is a part.
Systems thinking is not stepping back to look at the whole, the big picture,
or a higher level. Nor is it realizing that when a butterfly flaps its wings in one
place, that could cause a hurricane far away. This helps, but does not lead to the
major insights that emerge when the feedback loop structure of the system becomes visible. When this happens night becomes day. Systems thinking is the
first step to an even higher level: system dynamics, where instead of just thinking
in terms of system structure you model it.
Unit 2. General Systems Theory (GST)
37
Systems thinking revolves around a handful of concepts that anyone who
is determined to learn can master, with study and practice. The key concepts are:
− All systems are composed of inter-connected parts. The connections
cause behavior of one part to affect another. All parts are connected. A change
to any part or connection affects the entire system.
− The structure of a system determines its behavior. Structure is the pat-
tern of part connections, which is how the system is organized. System behavior
is at least a thousand times more dependent on connections than parts because
that’s what determines how the parts work together. To understand a system’s
gross behavior, understand its structure. To change a system’s gross behavior,
change its structure.
− System behavior is an emergent phenomenon. How a system behaves
cannot be determined by inspection of its parts and structure. This is because
parts are tightly coupled, the parts and structure are constantly changing, feedback loops are present, nonlinear relationships exist, behavior paths are history
dependent, the system is self-organizing and adaptive, emergent behavior is
counterintuitive, time delays exist, the human mind has very limited calculation
abilities, etc. Once you realize how complex the behavior dynamics of even a
simple system really is, you will never again assume you can look at a system
and predict how it will behave.
− Feedback loops control a system’s major dynamic behavior. A feedback
loop is a series of connections causing output from one part to eventually influence input to that same part. This circular flow results in large amplification,
delay, and dampening effects, which is what causes the gross behavior of the
system. Every part is involved in one or more feedback loops. Systems have more
feedback loops than parts, which causes unimaginable complexity. Feedback
loops are the main reason a system’s behavior is emergent.
The universe contains only two kinds of feedback loops: reinforcing and
balancing, also called positive and negative feedback loops.
A feedback loop occurs when a change in something ultimately comes
back to cause a further change in the same thing. If the further change is in the
same direction, it is a positive or reinforcing loop. If it is in the opposite direction
it’s a negative or balancing loop, also called a goal-seeking loop.
An example of a reinforcing loop is Population Growth. As population
goes up, so does births per year. As that goes up, so does future population. The
System analyses and control
38
loop goes round and round, growing exponentially until the loop hits its limits,
which are not shown.
An example of a balancing loop is Constrained Population Growth. Here
the constraint is carrying capacity, which is the maximum number of people a
system can support. Population will grow until it reaches this constraint, also
known as a limit or target.
Another example of a balancing loop is a Thermostat. Suppose you set the
target temperature to 65 degrees. The higher the target the greater the temperature
gap. The greater the gap the more heat that flows into the system. That increases
the temperature. As this goes up the temperature gap goes down. It keeps going
down until the gap is zero, at which point the system has reached the target.
These are causal loop diagrams. They can't be simulated but are very useful for simple or high level feedback loop modeling.
Arrows indicate that one node influences another. Solid arrows are a direct relationship. One node varies directly with another. If A goes up then so
does B, or if A goes down then so does B. Dashed arrows are an inverse relationship. If A goes up then B goes down and vice versa. As simple as models like
these are, they can allow problem solvers to understand the relevant behavior of
complex systems well enough to solve surprisingly difficult problems [3].
COMPREHENSION CHECK
20. Decide whether the following statements are true or false (T/F) by
referring to the information in the text. Then make the necessary changes
so that the false statements become true.
1. Traditional analysis focuses on interaction between system’s elements.
2. A change to a part of the system does not affect the entire system.
Unit 2. General Systems Theory (GST)
39
3. A feedback loop is system structure that causes output from one node to
eventually influence input to another node.
4. A feedback loop is like an input, but its origin is from within the system
itself, not from outside the system.
5. A feedback loop is either negative or balancing.
6. The behavior of all dynamics systems is generated by its boundaries.
7. The important behavior of a system emerges from its key feedback
loops.
8. Positive feedback loops are effective for creating change, but generally
result in negative consequences if not moderated by negative feedback loops.
9. Negative feedback loops are effective for resisting change.
21. Think about a system and try to determine feedback loops
controlling the system’ behavior.
SUPPLEMENTARY READING
THE ICEBERG MODEL
One systems thinking model that is helpful for understanding global issues is the iceberg model. We know that an iceberg has only 10 percent of its
total mass above the water while 90 percent is underwater. But that 90 percent is
what the ocean currents act on, and what creates the iceberg’s behavior at its tip.
Global issues can be viewed in this same way.
LEVELS OF THINKING
1. The Event Level
The event level is the level at which we typically perceive the world–for
instance, waking up one morning to find we have caught a cold. While problems
observed at the event level can often be addressed with a simple readjustment,
the iceberg model pushes us not to assume that every issue can be solved by
simply treating the symptom or adjusting at the event level.
2. The Pattern Level
If we look just below the event level, we often notice patterns. Similar
events have been taking place over time — we may have been catching more
colds when we haven’t been resting enough. Observing patterns allows us to
forecast and forestall events.
System analyses and control
40
3. The Structure Level
Below the pattern level lies the structure level. When we ask, “What is
causing the pattern we are observing?” the answer is usually some kind of struc-
ture. Increased stress at work due to the new promotion policy, the habit of eating
poorly when under stress, or the inconvenient location of healthy food sources
could all be structures at play in our catching a cold. According to Professor John
Gerber, structures can include the following:
Physical things – like vending machines, roads, traffic lights or terrain.
Organizations – like corporations, governments, and schools.
Policies – like laws, regulations, and tax structures.
Ritual – habitual behaviors so ingrained that they are not conscious.
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