Abstract: A control system is implemented by provision of parts which are data structures with identities, properties, and references to other parts, and clusters which are structures of associated parts. Clusters are assembled into meanings, and contexts are built from meanings and logic components. A current behavior expression consisting of a cluster is established and a meaning analysis procedure searches a set of meanings in a current context for correspondence between one or more meanings and the current behavior expression. When correspondence is found, further analysis switches the current behavior expression to a meaning matched in the current context. The process continues, switching context if necessary, until no meaning can be matched to a portion of the current behavior expression. Those portions of the current behavior expression for which no meaning is found represent primitive actions which are executed to carry out a system intention.