Holon (philosophy)
A holon (, from , holos, 'whole' and , -on, 'part') is something that is simultaneously a whole in and of itself, as well as a part of a larger whole. In other words, holons can be understood as the constituent part–wholes of a hierarchy. Holons are sometimes discussed in the context of self-organizing holarchic open (SOHO) systems. The word holon () is a combination of the Greek holos () meaning 'whole', with the suffix -on which denotes a particle or part (as in proton and neutron). According to Arthur Koestler, holons are self-reliant units that possess a degree of independence and can handle contingencies without asking higher authorities for instructions (i.e., they have a degree of autonomy). These holons are also simultaneously subject to control from one or more of these higher authorities. The first property ensures that holons are stable forms that are able to withstand disturbances, while the latter property signifies that they are intermediate forms, providing a context for the proper functionality for the larger whole. The holon represents a way to overcome the dichotomy between parts and wholes, as well as a way to account for both the self-assertive and the integrative tendencies of organisms. The term was coined by Arthur Koestler in The Ghost in the Machine (1967). In this way, a holon is a subsystem within a larger system: it is simultaneously an evolving structure while also a part of a greater system composed of other holons. Holons are sometimes discussed in the context of self-organizing holarchic open (SOHO) systems. Prior to introducing the term holon itself, Koestler articulated the concept in The Act of Creation (1964), in which he refers to the relationship between the searches for subjective and objective knowledge:

Einstein's space is no closer to reality than Van Gogh's sky. The glory of science is not in a truth more absolute than the truth of Bach or Tolstoy, but in the act of creation itself. The scientist's discoveries impose his own order on chaos, as the composer or painter imposes his; an order that always refers to limited aspects of reality, and is based on the observer's frame of reference, which differs from period to period as a Rembrant nude differs from a nude by Manet.Koestler would finally propose the term holon in The Ghost in the Machine (1967), using it to describe natural organisms as composed of semi-autonomous sub-wholes (or, parts) that are linked in a form of hierarchy, a holarchy, to form a whole. The title of the book itself points to the notion that the entire 'machine' of life and of the universe itself is ever-evolving toward more and more complex states, as if a ghost were operating the machine. The first observation was influenced by a story told to him by Herbert A. Simon—the 'parable of the two watchmakers'—in which Simon concludes that complex systems evolve from simple systems much more rapidly when there are stable intermediate forms present in the evolutionary process compared to when they are not present. The second observation was made by Koestler himself in his analysis of hierarchies and stable intermediate forms in non-living matter (atomic and molecular structure), living organisms, and social organizations. References

Further reading
Koestler, Arthur. [1967] 1990. The Ghost in the Machine . London: Hutchinson (Penguin Group). . Mella, Piero. 2009. The Holonic Revolution Holons, Holarchies and Holonic Networks: The Ghost in the Production Machine. Pavia University Press. . Simon, Herbert A. 1990. The Sciences of the Artificial (6th ed.). Cambridge, MA: MIT Press. . See also
Holism
Unity of opposites

External links
 Arthur Koestler text on holon

Holism
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