A living system is a Complex System that actively and autonomously upholds its System Boundary by exchanging energy and information with its Environment, thus “importing” order and staying in a Non-equilibrium Steady State.
How does the living organism avoid decay? The obvious answer is: By eating, drinking, breathing and (in the case of plants) assimilating. The technical term is metabolism.Schrödinger (1944), 75. This so-called metabolic view is opposed to the genetic or replication-first view of life.
What an organism feeds upon is negative entropy. Or, to put it less paradoxically, the essential thing in metabolism is that the organism succeeds in freeing itself from all the entropy it cannot help producing while alive.ibid., 76
A living system is subject to Adaptation and Evolution.
More specifically, living systems exist in near-critical states
because this maximises their information-processing capacity –
“evolutionary forces [keep them] poised at the edge of a Phase
Transition, or what amounts to the same thing, away from any
Attractor.”DeLanda (2002), 79
Living systems can … be characterized as systems that dynamically avoid attractors.This sounds like a contradiction to e.g. Friston (2017): “Complex systems are self-organising because they possess attractors. … Any time there’s a deviation from the attractor, this triggers flows of thoughts, feelings and movements that eventually take you back to your cycle of attracting, familiar states.” This is resolved two paragraphs below: “Of course, climbing out of one attractor just pushes the problem back to a higher-dimensional phase space, in which the system is again in the basin of some attractor. It is therefore possible to view evolution as a repeated iteration of the process whereby a system climbs out of one attractor into a higher-dimensional phase space, only to find itself in the basin of a higher-dimensional attractor, a process that gives evolutionary significance to the phrase ‘out of the frying pan, into the fire!’” (Langton 1992, 85)
The periodic regime is characterized by limit-cycle or fixed-point attractors, while the chaotic regime is characterized by strange attractors, typically of very high dimension. Living systems need to avoid either of these ultimate outcomes, and must have learned to steer a delicate course between too much order and too much chaos—the Scylla and Charybdis of Dynamical Systems.
They apparently have done so by learning to maintain themselves on extended transients—i.e., by learning to maintain themselves near a “critical” transition. Once such systems emerged near a critical transition, evolution seems to have discovered the natural information-processing capacity inherent in near-critical dynamics, and to have taken advantage of it to further the ability of such systems to maintain themselves on essentially open-ended transients.ibid.
Examples of living systems are biological and Social Systems.
- Brander (2022): “Coevolution creates living complexity”
- Deacon (2011): Incomplete Nature
- DeLanda (2002): Intensive Science and Virtual Philosophy
- Dennett (2017): From Bacteria to Bach and Back
- Friston (2017): “The mathematics of mind-time”
- Langton (1992): “Life at the Edge of Chaos”
- Schrödinger (1944): “What Is Life?”