Rule Engine

A rule engine is a software implementing a logic-like rule-based system. It basically consists of:

• A fact base, which stores information about the state of the world in the form of facts.
• A rule base, which stores rules describing how to process certain facts stored in fact bases.

• An inference engine, which controls the process of selecting and executing rules which can fire on the basis of certain states of the fact bases.

Rule engines are commonly used for expert systems, for which similar requirements exist as for reasoning techniques of autonomous agents in multi-agent simulation models. In OCOPOMO, agents’ processors are rule engines that take facts represented as logic-like clauses and put them together according to rules of inference to produce new clauses representing new facts. The input facts are taken from fact bases and the output facts are inserted into fact bases.  The totality of the fact bases available to each agent (equivalently, each rule engine) constitutes the environment as perceived by the agent.

S. Moss, R. Meyer, U. Lotzmann, M. Kacprzyk, M. Roszczynska and C. Pizzo (2010): D5.1 Scenario, policy model and rule-based agent design. Deliverable 5.1. OCOPOMO, 2010.

U. Lotzmann and R. Meyer (2011): A Declarative Rule-Based Environment for Agent Modelling Systems. In: The Seventh Conference of the European Social Simulation Association, ESSA 2011, Montpellier, 2011.