Since January 2008, NARS is developed as open source software at http://code.google.com/p/open-nars/.
It is a Java program that demonstrates the implemented NARS functionalities. You can either open a HTML file to run it as an applet, or download a JAR file (about 300K), and run it locally as an application by typing the following line in a command window:
java -jar "NARS.jar"
Two types of example are available, one showing representative single inference steps, and the other representative multi-step inference processes. After trying them, you can modify them, as well as make your own examples.
It is a Prolog program that implements all the inference rules in NAL 1-6, without memory structure and control mechanism for multiple-step inference. The source code comes with a user's guide and examples. The examples are tested with SWI-Prolog.
All the NAL truth-value functions are collected in a spreadsheet file NAL-TruthFunctions.xls.
The file contains three tables showing the relations among uncertainty measurements, the truth-value functions of the one-premise rules, and the truth-value functions of the two-premise rules, respectively. In each table, the input values can be modified, and the outputs of the functions change accordingly. The system parameters used in the functions can also be adjusted.