Extend the definition of ebg so that after it constructs a new rule, it asserts it to the logic database where it may be used in future queries. Test the performance of the resulting system using a theory for a suitably rich domain. You might do this by constructing a theory for a domain of your choice, or extending the theory from the cup example to allow it to explain different types of cups such as Styrofoam cups, cups without handles, etc.