You will see more examples of how inheritance works in the Database and other Units.
Note that it's not just Rules that can be overridden—Designs can be overridden as well. One Project can reference others in kBridge and you have already seen that all Projects reference the BaseLibrary as shown below.
If we were to create a Design named Block in the MyTable project above, it would override the one defined in the BaseLibrary. Just as in a mixin list, the Design that is higher in the reference list is the one that "wins." (We don’t recommend overriding the Block Design, though!)