perfect system

A perfect system, is one in which an upper ontology can be perfected and reliably imposed by a ruleset. By definition, all variables are contrained, all interactions are known, all terms are exactly defined and each component of the system is optimally contructed to serve it's function.

A perfect system, by its nature must also be a closed system: an isolated system having no interaction with an environment. (Von Bertalanffy, p.3)
Principia Cybernetica

By contrast, an open system relies on an imperfect, active and evolving ontology which relies in turn more on mindset than on a ruleset. It is not perfect. It arises from constraint, precedent and means to self-organize - like the common law or any electoral system it is a series of imperfections raised to an art. A living ontology cannot be a perfect system because of its evolution and willingness to accomodate sometimes-arbitrary constraint. The naming conventions are an example of how attempts to define rules for any such open system are bound to fail to be comprehensive.