Holon

1. Any stable sub-whole in an organismic, cognitive, or social hierarchy which displays rule-governed behaviour and/or structural Gestalt constancy. Sub-wholes are intermediary structures at different levels in a series in ascending order of complexity, such that with respect to the lower levels they function as autonomous wholes, and with respect to the higher levels, they function as a dependent part. (In other words, towards its subordinate parts, it behaves as a self-contained whole, and towards its superior controls as a dependent part.) The relativity of the terms part and whole when applied to any of its sub-assemblies is a general characteristic of hierarchies. A hierarchically organized whole cannot be reduced to its elementary parts; but it can be dissected into its constituent branches of holons. A holon may also be conceived as a system of relations which is represented on the next higher level as a unit in another system of relations.

2. Biological holons are self-regulating open systems governed by a set of fixed rules which account for a holon's coherence, stability and its specific pattern of structure and function. In symbolic operations, holons are rule-governed cognitive structures variously called frames of reference, universes of discourse, algorithms, etc., each with its specific grammar or canon; with the strategies increasing in complexity on higher levels of each hierarchy.