Appendix 2: Glossary of rules for the viable system (Extracted from The Heart of Enterprise Beer, 1979) to which book the page numbers refer, taken from http://kybernetik.ch/dwn/Viable_System_Model.pdf

**Aphorisms**

The first regulatory aphorism It is not necessary to enter the black box to understand the nature of the function it performs (p.40)

The second regulatory aphorism It is not necessary to enter the black box to calculate the variety that it potentially may generate (p.47)

**Principles**

The first principle of organization

Managerial, operational and environmental varieties, diffusing through an institutional system, tend to equate; they should be designed to do so with minimum damage to people and to cost. (p.97)

**The second principle of organization**

The four directional channels carrying information between the management unit, the operation, and the environment must each have a higher capacity to transmit a given amount of information relevant to variety selection in a given time than the originating subsystem has to generate it in that time. (p.99)

**The third principle of organisation**

Wherever the information carried on a channel capable of distinguishing a given variety crosses a boundary, it undergoes transduction; the variety of the transducer must be at least equivalent to the variety of the channel (p.101)

**The fourth principle of organization**

The operation of the first three principles must be cyclically maintained through time without hiatus or lags. (p.258)

**Theorem**

Recursive system theorem

In a recursive organizational structure, any viable system contains, and is contained in, a viable system (p.118)

**Axioms**

**The first axiom of management**

The sum of horizontal variety disposed by n operational elements equals the sum of vertical variety disposed on the six vertical components of corporate cohesion (p.217)

**The second axiom of management**

The variety disposed by System Three resulting from the operation of the First Axiom equals the variety disposed by System Four (p.298)

**The third axiom of management**

The variety disposed by System Five equals the residual variety generated by the operation of the Second Axiom (p.298)

**Law**

The law of cohesion for multiple recursions of the viable system

The System One variety accessible to System Three of Recursion x equals the variety disposed by the sum of the metasystems of Recursion y for every recursive pair. (p.355)