From “Academic Resources : Autopoiesis“: “Systems are structure determined. That is, anything a system does at any moment in time is determined by its structure – its component bits and pieces, and the relationships between them.”
“Maturana and Varela are at pains to take account of the perspective of the observer when talking of systems and how they behave in relation to their environment. The behaviour of a system is something ascribed to it by someone observing it in interaction with its environment. Hence behaviour is not something that is ‘in’ a system, and to refer to how a system relates to its environment whilst trying to understand it as an autonomous entity violates that very notion of autonomy. This is why all of the mechanics of the process of Autopoiesis as described by Maturana and Varela are kept strictly within the bounds of the Autopoietic system. This strict requirement is enforced via concepts like ‘operational closure’ and ‘organizational closure.’
The consequences of this perspective are not always obvious. A good example however, is the immune system’s ability to distinguish between self and non-self. Varela has been pointing out for some time that this is an observed behaviour, produced by the operational dynamics of the immune system in its environment, and that it is wrong to look for some discriminatory recognition mechanism within the immune system. Attention should be focused on the internal dynamics of the immune system, and how this is affected by and affects its environment of operation in such a way as to give rise to the behaviour observed. A similar approach is taken to the nervous system.
Autopoietic theory of course recognises that systems exist within environments, relate to them, and at low enough material level are entirely open to them. ”