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Ternality Theory


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A ternary structured paradigm for cybernetics

We have arrived at a proposed structured paradigm consisting of three domains in a stratified arrangement. What would they contain? We are thoroughly familiar with the contents of the primary domain. It contains all the entities, concepts, and laws of classical natural science. We also know the contents of the secondary domain. It is well represented by the contents of Ashby's textbook (Ashby,1956). In other words, we are familiar with what structure within those domains looks like. The structure within the tertiary domain is rather less familiar than that in the first two, but we shall arrive at that after first considering what it would mean to have a structure across domains.

Figure button   The ternary domanial structure

As it happens, when we attempt to distribute concepts and laws into their appropriate domains, it rapidly becomes apparent that an entity, a concept or a law in one domain often, but by no means always, has its counterpart or equivalent in both of the other domains. A set of three such components, one in each domain and such that the three members of the set are recognisably the counterparts of each other in their respective domains, we call a 'tern'.

Figure button   'Tern' defined

The Principle of Ternality

If a sufficient number of terns are discovered, this justifies the postulation of a Principle of Ternality, stating that many such terns exist, and that they enable our knowledge to be expressed as having not only a structure within each domain, but also a structure which spreads across domains and ties them together in a structured whole. This not only enables us to work with structure across domains, as well as within domains; it also enables us to legitimise the inclusion of imparity and related tertiary matters within the structure in a way that was not possible with previous structured paradigms.

Some terns

I have identified Work as a tern (Stewart, 1989). This is because work can be primary, such as moving a pile of earth or winding up a clock, or secondary, such as adding up an invoice, or setting the hands of the clock, or it can be tertiary work, such as making aesthetic judgements or making moral decisions. The human abilities required by each of the three kinds of work are different, as also are the kinds of fatigue that can be produced by doing them. So Fatigue is also a tern. Also in connection with the doing of work, there is a tern of Laws of Requisite Powers, namely {requisite mechanical power—requisite variety—requisite tertiary power}. Several other terns were also identified, including Propagation {energy—differentiae—imparity} and {signal—message—judgement or wish}

In further work undertaken since the Principle of Ternality was first proposed, more than sixty terns have been identified, which may give some weight to the Principle, and some credibility to the proposed ternary structured paradigm.



© Copyright D J Stewart 1987, 1998, 2003. All rights reserved.