SATM 4.7.3 Variety Engineering

Managers are unable to make accurate predictions either about the organizations they manage or the environments within which those organizations are situated. Ashby (1956, An Introduction to Cybernetics, Methuen, London.) takes the credit because of his invention of the key concept of variety. The variety of a system is defined here as the number of possible stated it is capable of exhibiting. Obviously, variety is a subjective concept depending on the observer.

The problem for managers, as Ashby's "law of requisite variety" has it, it that only variety can destroy variety. In order to control a system, we need to have as much variety available to us as the system itself exhibits. 

What if we are faced (like managers) with systems exhibiting apparently massive variety? How can we cope with this? The answer is that we must either reduce the variety of the system we are confronting (variety reduction) or increase our own variety (variety amplification). This process of balancing varieties is known as "variety engineering" (Beer, 1979, The Heart of Enterprise, Wiley, Chichester.) 

Managers have to learn how to use variety reduces, filting out the vast complexity of operational and environmental variety and capturing only that of relevance to themselves and the organization. And they have to learn how to use variety amplifiers, amplifying their own variety vis-a-vis the operations and the organization's variety vis-a-vis its environment. 

(Jackson, 2000, Systems Approaches to Management, Kluwer Academic/Plenum Publishers. NY. P72~73)