Loom - Knowledge base

Loom is a knowledge base created in 1987.

#2649on PLDB

37Years Old

Loom is a language and environment for constructing intelligent applications. The heart of Loom is a knowledge representation system that is used to provide deductive support for the declarative portion of the Loom language. Declarative knowledge in Loom consists of definitions, rules, facts, and default rules. A deductive engine called a classifier utilizes forward-chaining, semantic unification and object-oriented truth maintainance technologies in order to compile the declarative knowledge into a network designed to efficiently support on-line deductive query processing.

Loom website
Loom first developed in Information Sciences Institute
Loom on HOPL
Read more about Loom on Semantic Scholar: 1.

Example from the web:

(defconcept air-base
             :is-primitive
                     (and military-installation
                     (exactly 1 name)
                     (at-least 1 runway-length)))