Heuristic.  A heuristic is a higher order psychological adaptation, a useful mental shortcut, an approximation, or a rule-of-thumb, specialised for certain classes of problem, for guiding search and enabling adaptive decision-making.

Hierarchy.  Hierarchy is the principle according to which entities meaningfully treated as wholes are built up of smaller entities which are themselves wholes.

Human Activity System.  A notional purposive system which expresses some purposeful human activity, activity which could in principle be found in the real world.

Please contact Argos Press to obtain information on licensing this site's content (such as this entry on System Dynamics). © Argos Press Pty Ltd, Canberra, 2003-2005. All rights reserved.