The Homeostat is one of the first devices capable of adapting itself to the environment; it exhibited behaviours such as habituation, reinforcement and learning through its ability to maintain

homeostasis In biology, homeostasis (British English, British also homoeostasis) Help:IPA/English, (/hɒmɪə(ʊ)ˈsteɪsɪs/) is the state of steady internal, physics, physical, and chemistry, chemical conditions maintained by organism, living systems. Thi ...

in a changing environment. It was built by

William Ross Ashby W. Ross Ashby (6 September 1903 – 15 November 1972) was an English psychiatrist and a pioneer in cybernetics, the study of the science of communications and automatic control systems in both machines and living things. His first name was not ...

in 1948 at

Barnwood House Hospital Barnwood House Hospital was a private mental hospital in Barnwood, Gloucester, England. It was founded by the Gloucester Asylum Trust in 1860 as Barnwood House Institution and later became known as Barnwood House Hospital.Royal Air Force The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) and ...

bomb control units with inputs,

feedback Feedback occurs when outputs of a system are routed back as inputs as part of a chain of cause-and-effect that forms a circuit or loop. The system can then be said to ''feed back'' into itself. The notion of cause-and-effect has to be handled ...

, and magnetically driven, water-filled

potentiometers A potentiometer is a three-terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider. If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat. The measuring instrum ...

. It illustrated his law of requisite variety — automatically adapting its configuration to stabilize the effects of any disturbances introduced into the system. In 1946, Ashby described the design of the units thus "Its principle is that it uses multiple coils in a milliammeter & uses the needle movement to dip in a trough carrying a current, so getting a potential which goes to the grid of a valve, the anode of which provides an output current." It was the realization of what he had described in 1946 as an "

Isomorphism In mathematics, an isomorphism is a structure-preserving mapping between two structures of the same type that can be reversed by an inverse mapping. Two mathematical structures are isomorphic if an isomorphism exists between them. The word is ...

making machine". When

Alan Turing Alan Mathison Turing (; 23 June 1912 – 7 June 1954) was an English mathematician, computer scientist, logician, cryptanalyst, philosopher, and theoretical biologist. Turing was highly influential in the development of theoretical com ...

heard of Ashby's intention to build the Homeostat, he wrote to Ashby to suggest that he could run a simulation on Turing's

Automatic Computing Engine The Automatic Computing Engine (ACE) was a British early Electronic storage, electronic Serial computer, serial stored-program computer designed by Alan Turing. It was based on the earlier Pilot ACE. It led to the MOSAIC computer, the Bendi ...

(ACE) instead of building a special machine. The first published account of the homeostat appeared under the title of "Design for a Brain" in the December 1948 issue of 'Electronic Engineering', where he speculates about a perfected homeostat that could eventually play chess "with a subtlety and depth of strategy beyond that of the man who designed it." In 1949 ''Time'' described it as "the closest thing to a synthetic brain so far designed by man". In 1952, Ashby demonstrated it at the ninth Macy conference on

cybernetics Cybernetics is a wide-ranging field concerned with circular causality, such as feedback, in regulatory and purposive systems. Cybernetics is named after an example of circular causal feedback, that of steering a ship, where the helmsperson m ...

. In the same year he published a description of the Homeostat in his influential book ''

Design for a brain A design is a plan or specification for the construction of an object or system or for the implementation of an activity or process or the result of that plan or specification in the form of a prototype, product, or process. The verb ''to design'' ...

''. In total, between 1946 and 1967, he wrote 38 entries about the Homeostat in his journal.Ashby's journal references to the Homeostat
The W. Ross Ashby Digital Archive. In her online biography of Ashby, Jill Ashby wrote of the Homeostat, that "In 1961, Ross took it with him to the Biological Computing Laboratory, University of Illinois and left it there when he retired in 1970. Apparently, it was damaged soon after that when the area where it was being kept was flooded."

References

External links

The Thinking Machine: W. Ross Ashby and the Homeostat

British Library The British Library is the national library of the United Kingdom and is one of the largest libraries in the world. It is estimated to contain between 170 and 200 million items from many countries. As a legal deposit library, the British ...

Science Blog, 20 April 2016.
The W. Ross Ashby Digital Archive
includes a biography, bibliography, letters, photographs, movies, and fully indexed images of all 7,189 pages of Ashby's 25 volume journal.

Principia Cybernetica Web, 1999. * ttp://pespmc1.vub.ac.be/ASC/HOMEOSTAT.html Homeostatin the

Principia Cybernetica Web Principia Cybernetica is an international cooperation of scientists in the field of cybernetics and systems science, especially known for their website, Principia Cybernetica. They have dedicated their organization to what they call "a computer-su ...

. {{Systems Cybernetics

See also

References

External links