Penny
Penny is an expert system development toolkit designed as a teaching aid for those interested in rule based systems. Built in 4D, Penny is released under an open source license and the current version is available for download here. Source code versions require at least 4D version 12 (not supplied) and are available in either Windows or Macintosh versions. A sponsored, compiled version is available for those people not requiring source code. Penny is a new initiative and is in the earliest stages of development; expect regular updates to the software.
Penny license agreement (please read first)
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