Classic is a family of knowledge representation (KR) systems designed for applications where only limited expressive power is necessary, but rapid responses to questions are essential. The Classic systems are based on description logics (DLs), which gives them an object-centered flavor, and thus most of the features available in semantic networks are also available in Classic. Classic has a framework that allows users to represent descriptions, concepts, roles, individuals and rules. Classic allows for both primitive concepts, similar to the classes and frames of other knowledge representation systems and object-oriented programming languages, and defined concepts, i.e. concepts that have both necessary and sufficient conditions for membership. Concepts are automatically organized into a generalization taxonomy and objects are automatically made instances of all concepts for which they pass the membership test. Another type of reasoning that Classic does is to detect inconsistencies in information that it is told. In the presence of defined concepts these operations are non-trivial and useful.
There are other implemented description logics besides the Classic systems. Some other implemented systems are mentioned on this site, or for more complete information about description logics, see the official description logic home page.
There are three members of the Classic family. They are:
Classic has been distributed to over 100 research institutions. The C version is a vital component of the PROSE and QUESTAR configuration products which have been used to configure over 4 billion dollars worth of AT&T and Lucent products. A demonstration application on configuring home theater systems has been developed in LISP Classic. A new web version of the configuration system is sometimes available.
Online tutorials (co-developed with Rich Thomason, Violetta Cavalli-Sforza, Cristina Conati, and Johanna Moore from University of Pittsburgh) are available for the LISP version as well as the NeoClassic version. The LISP tutorial was distributed from the University of Pittsburgh and may be available on pogo.isp.pitt.edu from ~ftp/pub/classic-tutorial. Rich Thomason is the Pitt contact for the tutorial. Both tutorials (LISP and NeoClassic) are available from these pages.
Related research activities in description logics include explaining inferences in description logic systems, pruning object presentation, extensible description logics, default representation, machine learning applied to description logics, etc.
LISP Classic and NeoClassic are available for non-commercial use They are also available for commercial use, though this requires previous negotiation of terms and conditions. You should be able to obtain a copy of LISP Classic or NeoClassic, but the distribution mechanism is currently broken. To obtain a copy of LISP Classic or NeoClassic, go to the Bell Labs open innovation site, http://open-innovation.alcatel-lucent.com/ The page for Classic, including NeoClassic, is https://open-innovation.alcatel-lucent.com/projects/classic/
For more information write to Peter F. Patel-Schneider (firstname.lastname@example.org)