Rule of Three
A local branching cap for adaptive recursive coordination.
A holon can have at most three direct children. Three is a maximum fan-out, not a requirement to keep three fixed seats alive.
If a manager has too much work, they can split it into up to three smaller chunks. If only one chunk is needed, they use one. If two are enough, they use two.
The Rule of Three bounds local complexity while still allowing large structures through recursion. It is intended to adapt: lanes can open, combine, fold, park or close as work changes. That makes the rule a topology constraint rather than a staffing chart.
Where this concept shows up
Local invariant
The child cap applies per holon. Recursive levels can therefore create larger structures without any single node coordinating an unbounded number of direct children.
Adaptive, not fixed
The programme's topology work uses OPEN/KEEP/FOLD/PARK/CLOSE style evaluation. Capacity should follow justified work rather than preserving empty roles.
Relationship to expert routing
The Rule of Three is an orchestration topology principle. Expert-selection caps and ±3 relevance neighborhoods are related design ideas but should not be silently treated as the same contract.
Source lineage
Concept pages preserve whether an idea is canonical, proposed or working theory. That label is independent from whether a related product feature is implemented.