> (b) another thing we could do is to try to introduce more meaning into
>     inheritance. Right now there is no "algebra" that will tell us anything
>     useful about what a subclass might be relative to its super classes.

Could you elaborate some more on this? I don't quite understand what you
mean.

When I think of added meaning related to inheritance, C++ comes to mind.
There it is used both as a means of code reuse and type extension, causing
designs to rely heavily (often unnecessarily) on inheritance.

Could you give some example about what type of added meaning you are
thinking about?


Thanks, -- Kris