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Ternary Analysis


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Domains of work

In Ternary Analysis, work is a tern (Stewart, 1989).

The primary component is the usual mechanical kind of work. Physical labour involving energy.

The secondary component involves the handling of information, such as calculating.

The tertiary component involves handling imparity-that is, judging between things and preferring some states of affairs to others.

Figure button   The tern of Work

There is often a leading domain, which characterises the type of work that is being performed-primary, secondary, or tertiary.

The tern of Machines

Similarly, many machines are designed to process essentially one component.

Just as many machines are designed to process essentially one component, so that the essential function of a primary machine is to handle energy, that of a secondary machine to handle information, and that of a tertiary machine to handle imparity.

Figure button   The tern of Machines

Laws of Requisite Power

There is a well-known law of mechanics to the effect that a primary machine needs to have a certain amount of power to be able to carry out its tasks. In the secondary domain, we have Ashby's Law, which says the same thing about the amount of information, or variety, that a secondary machine needs to carry out its tasks (Ashby,1956).

In human beings, there is an equivalent Law of Requisite Tertiary Power, so these three laws form a tern. Fatigue, too, has its three components and so is a another tern (Stewart, 1989). Most human work, however, usually contains all three components in some degree. There will be some physical labour, however little, an element of calculation or ratiocination, and a certain amount of evaluating or judging.



© Copyright D J Stewart 1999, 2003. All rights reserved.