James G. and Jessie MILLER describe in the following way the 20 critical subsystems in living systems (1990, p.159):
Subsystems which Process both Matter Energy and Information
1. Reproducer, the subsystem which is capable of giving rise to other systems similar to the one it is in.
2. Boundary, the subsystem at the perimeter of a system that holds together the components which make up the system, protects them from environmental stresses, and excludes or permits entry to various sorts of matter-energy and information.
Subsystems which Process Matter-Energy
3. Ingestor, the subsystem which brings matter- energy across the system boundary from the environment.
4. Distributor, the subsystem which carries inputs from outside the system or outputs from its subsystems around the system to each component.
5. Converter, the subsystem which changes certain inputs to the system into forms more useful for the special processes of that particular system.
6. Producer, the subsystem which forms stable associations that endure for significant periods among matter-energy inputs to the system or outputs from its converter, the materials synthetized being for growth, damage repair, or replacement of components of the system, or for providing energy for moving or constituting the system's outputs of products or information markers to its suprasystem.
7. Matter-energy storage, the subsystem which retains in the system, for different periods of time, deposits of various sorts of matter-energy.
8. Extruder, the subsystem which transmits matter-energy out of the system in the forms of products or wastes.
9. Motor, the subsystem which moves the system or parts of it in relation to part or all of its environment or moves components of its environment in relation to each other.
10. Supporter, the subsystem which maintains the proper spatial relationships among components of the system, so that they can interact without weighting each other down or crowding each other.
Subsystems which Process Information
11. Input transducer, the sensor subsystem which brings markers bearing information into the system, changing them to other matter-energy forms suitable for transmission within it.
12. Internal transducer, the sensory subsystem which receives, from subsystems or components within the system, markers bearing information about significant alterations in those subsystems or components, changing them to other matter-energy forms of a sort which can be transmitted within it.
13. Channel and net, the subsystem composed of a single route in physical space, or multiple interconnected routes, by which markers bearing information are transmitted to all parts of the system.
14. Timer, the subsystem which transmits to the decider information about time-related states of the environment or of components of the system. This information signals the decider of the system or deciders of subsystems to start, stop, alter the rate, or advance or delay the phase of one or more of the system's processes, thus coordinating them in time
15. Decoder, the subsystem which alters the code of information input to it through the input transducer or internal transducer into a "private" code that can be used internally by the system.
16. Associator, the subsystem which carries out the first stage of the learning process, forming enduring associations among items of information in the system.
17. Memory, the subsystem which carries out the second stage of the learning process, storing various sorts of information in the system for different periods of time.
18 Decider, the executive subsystem which receives information inputs from all other subsystems and transmits to them information outputs that control the entire system.
19. Encoder, the subsystem which alters the code of information input to it from other information processing subsystems, from a "private" code used internally by the system into a "public" code which can be interpreted by other systems in its environment.
20. Output transducer, the subsystem which puts out markers bearing information from the system, changing markers within the system into other matter-energy forms which can be transmitted over channels in the system's environment
In J.G. MILLER's original versions (1965, 1978), only 19 critical subsystems were described. The 20th., i.e. the "timer" was introduced by J. and J. MILLER (1990)
Note: The 20 critical subsystems are registered in their own alphabetic order in this encyclopedia.
- 1) General information
- 2) Methodology or model
- 3) Epistemology, ontology and semantics
- 4) Human sciences
- 5) Discipline oriented
To cite this page, please use the following information:
Bertalanffy Center for the Study of Systems Science (2020). Title of the entry. In Charles François (Ed.), International Encyclopedia of Systems and Cybernetics (2). Retrieved from www.systemspedia.org/[full/url]
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