Maude is a high-performance reflective language and system 
supporting both equational and rewriting logic specification 
and programming for a wide range of applications. Maude has 
been influenced in important ways by the OBJ3 language, which 
can be regarded as an equational logic sublanguage. Besides 
supporting equational specification and programming, Maude 
also supports rewriting logic computation.

Because Maude needs some help for finding its own files,
you may:
 - logout and login again, then run maude
 
 - run maude with explicit reference to its files' location
   $ MAUDE_LIB=/usr/share/maude/ maude
 
 - export the variable to the environment, then run maude
   $ export MAUDE_LIB=/usr/share/maude/
   $ maude
