Biomedical Engineering Reference
In-Depth Information
1.
INTRODUCTION
The historical framework and ideas presented here feature the disciplines
that spawned the science of complex systems (e.g., self-organizing, autopoietic
networks, dissipative structures, chaos, fractals). In particular, we use general
systems theory (GST), control system theory (i.e., cybernetics, homeodynam-
ics), and dynamical systems theory (nonlinear, chaotic), the forerunners of crea-
tive systems thinking, to formulate a coherent theory and elucidate the essential
properties of biological phenomena such as structural and functional organiza-
tion, regulatory control mechanisms, and robustness and fragility.
The defining aims of systems thinking
:
— The Believing: why do I see what I see?
— The Being: why do things stay the same?
— The Becoming: why do things change?
The notion of a system comprised of interdependent elements has been the
subject of human concern and inquiry for centuries. Man has explored the solar
system and the constellations since the beginning of recorded time. We, as a
species, have struggled with the complicated array of interconnected elements
that control our internal and external world. The more formal understanding of a
system, offered by systems science, as a complex of components and their inter-
actions has not changed dramatically through the years.
An inkling of systems science was anticipated by the
Gestalten
in physics, a
natural worldview proposed in the 1920s. According to the great leader in the
field of GST, Ludwig von Bertalanffy, the ideas of physical
Gestalten
were the
precursors intended to elaborate the most general properties of inorganic com-
pared with organic systems. It is worth mentioning that physicists study closed
systems, as compared with real systems, that communicate and exchange energy
(information) with the environment and thus self-organize, learn, and adapt. Of
particular note is the historical precedence that gave rise to the genesis of sys-
tems theory as a reaction to the confinement of reductionism and motivated by a
keen desire to reestablish the unity of science. Some aspects of intellectual tradi-
tion and scientific history are worthy of repetition.
Systems
was and remains a fashionable catchword. In the introduction to his
seminal topic,
General System Theory
(1), von Bertalanffy wrote in 1967 that
the concept of systems permeated all fields of science as well as popular think-
ing, jargon, and mass media. Common parlance continues to include concepts
such as adaptation, control, differentiation, dynamic behavior, hierarchy, robust-
ness, reliability, and sensitivity.
