The necessity of hierarchy for living systems.

We present a short critique of living systems and of hierarchy, and then present model hierarchy as the parent of other less elaborate schemes. Model hierarchy consists of a number of organizational levels, each a scaled model of the entire system under consideration. Cross-hierarchy coherence is paramount. The model-hierarchical representation of an organism splits into two partial hierarchies, one of the model levels, the other of the intervening complex regions. We propose that model hierarchy is the most fundamental aspect of living systems, in that it permits the operation of all other characteristics of life. We present a computational analogue to model hierarchy - AQUARIUM - and integrate the two representations. Neural processing suffers from an omission in its formulation, and we link this processing duality to classical simulation of quantum processes. We describe the way in which inter-organizational transit may be accomplished by means of a generic form of quantum error correction. We conclude that model hierarchy is fundamental to the existence of living systems, as is the classical simulation of quantum processes.