This is an outdated version published on 2022-02-24. Read the most recent version.

Only behaviour can destroy behaviour

A useful behavioural interpretation of Ashby?


  • James Bryant Cybernetics society (UK)


Behavioural, Behaviour, Cybernetics, Variety, Requisite, Equilibrium, control, Displacement


Currently, we find ourselves with insufficient remedy to the way we behave towards each other and the planet and are in desperate need of unlocking, conceptually and practically, the creation of a better behaving world.

One potential source for such an enlightenment is Cybernetics.

This paper proposes a behavioural model based on displacement and control, derived from a critical examination and development of Ashby’s Law of Requisite Variety presented in An introduction to cybernetics. This outcome is that Only Behaviour can destroy behaviour and the Laws of Requisite Behaviour:

  1. A system experiencing a force that might displace it responds by generating a behaviour
  2. The purpose of the behaviour is to enable the system to continue to pursue its intent
  3. A displacement is always the result of a behaviour and a behaviour always causes a displacement.
  4. That behaviour may be to adjust the intent so that it may continue to be pursued
  5. Intents exist in a hierarchy and less important intents will be abandoned in favour of more important intents if required.

Hiding in plain sight within An introduction to cybernetics (Ashby R 1957)  is that cybernetics is about the behaviour of machines:

Cybernetics, too,

is a “theory of machines”, but it treats, not things but ways of

behaving. It does not ask “what is this thing?” but “what does it


When Ashby considers biological organisms he is most concerned with survival, and on the act of blocking communication:

the concepts of “survival” and “stability” can be brought

into an exact relationship;

In general, then, an essential feature of the good regulator is

that it blocks the flow of variety from disturbances to essential-variables


Ashby’s application of cybernetics to human behaviour is only explicit in explaining human behaviour when it parallels the regulation of a machine. However, placing Ashby’s “ways of behaving” as the central tenet provides the basis for an evolution of Behavioural Cybernetics.

This Behavioural hypothesis considers disturbance to generate Requisite Behaviour: the behaviour needed to control displacement to an extent that enables the organism to achieve its intents.

Variety of behaviour arises from a strategy of variable regulation towards displacement that ranges from zero to full control: ‘blocking’ is not the only successful strategy for survival. This is supported by research and observation from disciplines, including biological, behavioural and social sciences.

It is expected that subsequent papers on Requisite Behaviour will reveal new and much needed insight into the use of this interpretation of Cybernetics to effect change in human systems behave better: the requisite behaviour to achieve a better behaving world.


Keywords: Behavioural, Behaviour, Cybernetics, Variety, Requisite, Equilibrium, control, Displacement