I agree with Moon also. And I agree that pg. 56 is ok too. It is pg.
69 that is a little shaky, and pg. 324 DEFINITELY states that NIL and T
are defined with DEFCONSTANT.
OK, we all agree that it is an error to redefine built-in constants,
whether or not we think of them as having been created by defconstant.
The manual should be made consistent on this point.
-- Scott