Not really.  I think I included all the libraries needed (except base, of course), didn't I?

A week ago I made a small change to a previous iteration of the project and suddenly half the tests (even simple ones) were failing.  The faults seemed to be totally unrelated to the changes.

I suspect the problem has to do with my assumption that I can change the way NATURAL and NATURAL_REF classes work.  I say this because the two failures I pointed out fail in odd ways.  In `is_negative' I pass an agent with closed target which is a local variable just created, but when `is_negative' is run in the debugger, the type reported for the closed target is NOT the local but is the type of the enclosing class.  ???