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History of Cybernetics and Systems Science
Perhaps one of the best ways of seeing the strength and the impact of the systemic approach is to follow its birth and development in the lives of men and institutions.
The Search for New Tools
We need new tools with which to approach organized complexity, interdependence, and regulation. These tools emerged in the United States in the 1940s from the cross-fertilization of ideas that is common in the melting pot of the large universities.
In illustrating a new current of thought, it is often useful to follow a thread. Our thread will be the Massachusetts Institute of Technology (MIT). In three steps, each of about ten years, MIT was to go from the birth of cybernetics to the most critical issue, the debate on limits to growth. Each of these advances was marked by many travels back and forth--typical of the systemic approach--between machine, man, and society. In the course of this circulation of ideas there occurred transfers of method and terminology that later fertilized unexplored territory.
In the forties the first step forward led from the machine to the living organism, transferring from one to the other the ideas of feedback and finality and opening the way for automation and computers. In the fifties it was the return from the living organism to the machine with the emergence of the important concepts of memory and pattern recognition, of adaptive phenomena and learning, and new advances in bionics (Bionics attempts to build electronic machines that imitate the functions of certain organs of living beings.): artificial intelligence and industrial robots. There was also a return from the machine to the living organism, which accelerated progress in neurology, perception, the mechanisms of vision. In the sixties MIT saw the extension of cybernetics and system theory to industry, society, and ecology.
Three men can be regarded as the pioneers of these great breakthroughs: the mathematician Norbert Wiener, who died in 1964, the neurophysiologist Warren McCulloch, who died in 1969; and Jay Forrester, professor at the Sloan School of Management at MIT. There are of course other men, other research teams, other universities--in the United States as well as in the rest of the world--that have contributed to the advance of cybernetics and system theory. I will mention them whenever their course of research blends with that of the MIT teams.
Do the following tasks:
- Make up a detailed plan of each part of the text.
- Retell each part of the text separately.
A robot is defined as a mechanical device which can be programmed to perform some task. An automatic machine, stationary or mobile, containing a manipulator and a reprogrammable device of program control, is called an industrial robot.
Industrial robots are made up of some basic components: the manipulator, the control and the power supply. Being hydraulically, pneumatically or electrically drive, the manipulator performs the useful functions of the robot. Engineers consider robots to have same manipulators with up to seven degrees of coordinated motions. Feedback devices on the manipulator provide information on its motions and positions to the robot control, the control storing the necessary motions of the robot in its memory. The control directs the manipulator operations by means of a program upon a command. A power supply is certain to provide energy for driving the manipulator.
Industrial robots perform production processes better and faster than men. The job changing, robots may be reprogrammed. They can imitate the manual actions of people, being able to substitute manual actions of man. Thus, the industrial robot is the most important form of automated means.
Do the following tasks:
- Translate into Russian.
- Write a summary to it.
Norbert Wiener had been teaching mathematics at MIT since 1919. Soon after his arrival there he had become acquainted with the neurophysiologist Arturo Rosenblueth, onetime collaborator of Walter B. Cannon (who gave homeostasis its name) and now at Harvard Medical School. Out of this new friendship would be born, twenty years later, cybernetics. With Wiener's help Rosenblueth set up small interdisciplinary teams to explore the no man's land between the established sciences.
In 1940 Wiener worked with a young engineer, Julian H. Bigelow, to develop automatic range finders for antiaircraft guns. Such servomechanisms are able to predict the trajectory of an airplane by taking into account the elements of past trajectories. During the course of their work Wiener and Bigelow were struck by two astonishing facts: the seemingly "intelligent" behavior of these machines and the "diseases" that could affect them. Theirs appeared to be "intelligent" behavior because they dealt with "experience" (the recording of past events) and predictions of the future. There was also a strange defect in performance: if one tried to reduce the friction, the system entered into a series of uncontrollable oscillations.
Impressed by this disease of the machine, Wiener asked Rosenblueth whether such behavior was found in man. The response was affirmative: in the event of certain injuries to the cerebellum, the patient cannot lift a glass of water to his mouth; the movements are amplified until the contents of the glass spill on the ground. From this Wiener inferred that in order to control a finalized action (an action with a purpose) the circulation of information needed for control must form "a closed loop allowing the evaluation of the effects of one's actions and the adaptation of future conduct based on past performances." This is typical of the guidance system of the antiaircraft gun, and it is equally characteristic of the nervous system when it orders the muscles to make a movement whose effects are then detected by the senses and fed back to the brain.
Thus Wiener and Bigelow discovered the closed loop of information necessary to correct any action--the negative feedback loop--and they generalized this discovery in terms of the human organism.
During this period the multidisciplinary teams of Rosenblueth were being formed and organized. Their purpose was to approach the study of living organisms from the viewpoint of a servomechanisms engineer and, conversely, to consider servomechanisms with the experience of the physiologist. An early seminar at the Institute for Advanced Study at Princeton in 1942 brought together mathematicians, physiologists, and mechanical and electrical engineers. In light of its success, a series of ten seminars was arranged by the Josiah Macy Foundation. One man working with Rosenblueth in getting these seminars under way was the neurophysiologist Warren McCulloch, who was to play a considerable role in the new field of cybernetics. In 1948 two basic publications marked an epoch already fertile with new ideas: Norbert Wiener's Cybernetics, or Control and Communication in the Animal and the Machine, and The Mathematical Theory of Communication by Claude Shannon and Warren Weaver. The latter work founded information theory.
Do the following tasks:
- Define the main facts mentioned in the text.
- Ask 10 questions to the text.
- Write down a resume of it.
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