Basic autopoiesis

The notion of boundary is, in fact, one central concept in the theory of autopoiesis. Inside the boundary of a cell, many reactions and correspondingly many chemical transformations occur. However, despite all these chemical processes, the cell always maintains its own identity during its homeostasis period. This is because the cell (under steady-state conditions and/or homeostasis) regenerates within its own boundary all those chemicals that are being destroyed or transformed, ATP, glucose, amino acids, proteins, etc. 

The chain of processes occurring inside the boundary essentially serves the purpose of self-sustenance, or auto-maintenance. Of course, this takes place at the expense of nutrients and energy coming from the medium. As discussed earlier, the cell is a dissipative, open system. 

From these simple, basic observations, Maturana and Varela (often referred to as the Santiago school) arrived at a characterization of living systems based on the autopoietic unit. An autopoietic unit is a system that is capable of sustaining itself due to an inner network of reactions that regenerate the system s components (Varela etal., 1974 Maturana and Varela, 1980 Luisi, 1997 Maturana and Varela, 1998 Varela, 2000 Luisa et al, 1996). 

In other words, it can be said that an autopoietic system organizes the production of its own components, so that these components are continuously regenerated and can therefore maintain the very network process that produces them. 

It is perhaps pertinent at this point to cite a recent definition by Maturana himself (in Poerksen, 2004)  

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We go back now to basic autopoiesis, in order to consider what came as an interesting, and unexpected, development of this theory. By unexpected, I mean that even the authors of the Santiago school had not foreseen it. This is social autopoiesis. The main feature of autopoiesis is self-maintenance due to a process of self-generation from within. Although this concept came from the analysis of a living cell, it can be metaphorically applied to social systems. 

The question of the criteria of autopoiesis is formalized at length, but not always clearly, in the primary literature on autopoiesis. Varela, in his latest book (2000), has simplified these criteria into three basic ones, which can he expressed as follows Verify (1) whether the system has a semi-permeable boundary that (2) is produced from within the system and (3) that encompasses reactions that regenerate the components of the system. Thus, a virus is not an autopoietic system, as it does not produce the protein coat of its boundary or the nucleic acids (the host cell does this, and it is living). A computer virus is also not autopoietic, as it needs a computer system that is not produced hy the virus itself. A growing crystal is not autopoietic, as the components are not generated from an internalized network of reactions. 

One advantage of the idea of autopoiesis is its extreme simplicity. This comes at the cost of a lack of structural and mechanistic details. Ganti s chemoton provides a more detailed and more complex view of the unit of cellular life (Ganti, 1975 2003). Let s now sketch the basic theory of the chemoton in order to draw a comparison with autopoiesis. 

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