e many incompatible "possible worlds", which, if properly
documented, will be recognized as incompatible.  We can define Newtonian
and relativistic mechanics using the same language -- that's my hope for
the SUO.
      The question your comment raises is whether there are some pairs
of concepts so fundamentally different that no common set of defining axioms

can serve to define both.  If we define both time points and time intervals,
and allow the users to decide which representation of time is best for
th