Holons and System Adaptation

Holons are the basis for building very scalable yet simple architectures. They spring from the observation made by Koestler that the concepts of 'whole' and 'part' have no absolute meaning in the reality. A whole or a part can be easily identified in many contexts but at the same time they can be seen as opposite. This philosophical concept has a perfect correspondence with software architecture. Nowadays, it is very diffused to approach complex systems as systems of systems. They can be seen as intrinsically recursive when considering that each of the composing systems may be decomposed into its components that in turn may be individually addressed or regarded as an assembly of (sub-) systems/components/classes. Each of the parts at whatever level of abstraction has the dignity of a complete entity (a whole) but at the same time it may be further exploded at finer level of details (as parts). Holons offer a great way for representing complex systems and solving several real-world problems but their recursive, dynamic nature may be a challenge at design time. In this talk, holons will be the common denominator of a path that discusses the design of holonic systems and their great contribution in achieving runtime system-level adaptation of cognitive multi-agent systems, for instance during the execution of norm-constrained workflows. The presented contribution of holons towards system adaptation lies in the hierarchical self-similar structure of the holonic architecture. They allow the decomposition and representation of intentional systems that achieve effective goal-oriented solutions, at the same time they become a proficient structure to be learnt for future reuse.