Systems and Observers

Ashby’s system triad

W. Ross Ashby in his 1956 book An Introduction to Cybernetics, in section 3/11 answers the question “What is a “system”?”:

Our first impulse is to point at the pendulum and to “the system is that thing there”. This method, however, has a fundamental disadvantage: every material object contains no less than an infinity of variables and therefore of possible systems. The real pendulum, for instance, has not only length and position; it has also mass, temperature, electric conductivity, crystalline structure, chemical impurities, some radio-activity, velocity, reflecting power, tensile strength, …

He goes further to state that (emphasis mine).

Any suggestion that we should study “all” the facts is unrealistic, and actually the attempt is never made. What is try is that we should pick out and study the facts that are relevant to some main interest that is already given.

So, Ashby makes a clear distinction between “machine”, “system” and “model”.

In Design for a Brain in chapter 2/5 Ashby explains in more details his use of the word system:

Because any real ‘ machine ‘ has an infinity of variables, from which different observers (with different aims) may reasonably make an infinity of different selections, there must first be given an observer (or experimenter); a system is then defined as any set of variables that he selects from those available on the real ‘ machine ‘. It is thus a list, nominated by the observer, and is quite different in nature from the real ‘ machine ‘. Through- out the book, ‘ the system ‘ will always refer to this abstraction, not to the real material ‘ machine ‘.

We strictly follow Ashby’s interpretation and define the basic terms like this:

  • Machine (that what is observed in a common phenomenal domain of interaction by two or more observers)
  • System (an organized set of variables selected by an observer to study the machine’s function and/or behaviour)
  • Model (an organized structure made from selected system variables by the observer for sharing with other observers).
  • Variable (noun) – a selected element, feature, or factor (property) of the machine that is liable to variation or change. A variable must be a quantifiable entity (scalar) within well defined boundaries. The current state of the system is then defined by the vector containing current values of all selected variables.


  • Many authors do not make a clear distinction between machine and system and between system and model. The word system is frequently used to describe any of the three. The difference is, however, the same as between an observed triangular object (machine) or a drawing shaped as a triangle (model) and the concept of a triangle (system). A system is just an idealized concept of the machine containing a selected set of the machine’s properties.
  • Systems and machines exist in two different (non-intersecting) phenomenal domains that are internal and external to the observer. The model and the machine, however, reside in the same phenomenal domain external to the observer and can be readily investigated by other observers.

So, the system is not something that is already given and exist in the real world independent from us observers, That’s the the machine. The system is the result of as observes exercising our free will and selecting a finite list of variables and finding their interrelationships by observing (or imagining) the inner working of the machine.

When this is understood, then it is not too much of a stretch of our imagination to conclude that things like structure, hierarchy, information, etc. are also just constructs used to aid our ability to discuss systems and build models for sharing our observations with other observers.

HvFoerster’s Observer Triad

Heinz von Foerster in his famous speech from 1979 Cybernetics of Cybernetics speaks about:

three concepts that are in a triadic fashion connected to each other. They are: first, the observers; second, the language they use; and third, the society they form by the use of their language.

He goes further to state:

This interrelationship can be compared, perhaps, with the interrelationship between the chicken, and the egg, and the rooster. You cannot say who was first and you cannot say who was last. You need all three in order to have all three.

We beg to differ. We think that there is a clear historical timeline in place. In the beginning there was the lone observer who, by observing their environment observed some other entities that behave in a strangely familiar way and started socializing with them. And then these observers invented signs, sounds and words to describe (model) that what they observed. Not sure where the chicken, rooster or egg fits in, though.

Earlier in the same speech Foerster recognizes:

… Maturana’s proposition, which I shall now baptize “Humberto Maturana’s Theorem Number One”:

“Anything said is said by an observer.”

And proceeds with the blunder of adding a completely superfluous corollary:

… to Maturana’s Theorem … which, in a modesty, I shall call “Heinz von Foerster’s Corollary Number One”:

“Anything said is said to an observer.”

In fact the whole statement from Maturana’s Biology of Cognition, written back in 1970 reads like this:

“Anything said is said by an observer. In his discourse the observer speaks to another observer, who could be himself;”

Caution: Work in progress from this point forward !

Scientific Explanations

Maturana in Ontology of Observing (1988) states:

there are no such things as scientific observations, scientific hypotheses or scientific predictions: there are only scientific explanations and scientific statements

He further explains that:

the criterion of validation of scientific explanations entails four operational conditions:

a) The specification of the phenomenon to be explained through the stipulation of the operations that a standard observer must perform in his or her praxis of living in order to also be a witness of it in his or her praxis of living.

b) The proposition, in the domain of operational coherences of the praxis of living of a standard observer, of a mechanism, a generative mechanism, which when allowed to operate gives rise as a consequence of its operation to the phenomenon to be explained …
…. the phenomenon to be explained and its generative mechanism take place in different non-intersecting phenomenal domains in the praxis of living of the observer

c) The deduction, that is, the computation, in the domain of operational coherences of the praxis of living of the standard observer entailed by the generative mechanism proposed in (b), of other phenomena that the standard observer should be able to witness in his or her domain of experiences as a result of the operation of such operational coherences, and the stipulation of the operations that he or she should perform in order to do so.

d) The actual witnessing, in his or her domain of experiences, of the phenomena deduced in (c) by the standard observer who actually performs in his or her praxis of living the operations stipulated also in (c).

The above citations contain several, fundamental revelations about autopoiesis and systems sciences in general:

  1. The observer is an autopoietic (living) system with the capability to explain (model) phenomena observed in its praxis of living;
  2. This explanations can be interpreted by other standard observers living in the same phenomenal domain
  3. The praxis of living of the observers spans through two adjacent but non-intersecting phenomenal domains:
    • the domain of interactions (function) of its elements as a composite entity
    • the domain of interactions in the environment as a simple unity (behaviour).

  • The oldest type of modelling is storytelling, first by pictures and then by spoken and written language.
  • The model is a message produced by the observer to communicate with other observers.
  • Except DNA where the model is part of the machine?
  • All autopoietic (living) machines are observers trying to make sense from their environment?
  • What is the relationship between life (autopoiesis), observation and cognition?