logical

logical adj.  [from the technical term `logical device',
   wherein a physical device is referred to by an arbitrary
   `logical' name] Having the role of.  If a person (say, Les
   Earnest at SAIL) who had long held a certain post left and were
   replaced, the replacement would for a while be known as the
   `logical' Les Earnest.  (This does not imply any judgment on the
   replacement.)  Compare {virtual}.

   At Stanford, `logical' compass directions denote a coordinate
   system in which `logical north' is toward San Francisco,
   `logical west' is toward the ocean, etc., even though logical
   north varies between physical (true) north near San Francisco and
   physical west near San Jose.  (The best rule of thumb here is that,
   by definition, El Camino Real always runs logical north-and-south.)
   In giving directions, one might say: "To get to Rincon Tarasco
   restaurant, get onto {El Camino Bignum} going logical north."
   Using the word `logical' helps to prevent the recipient from
   worrying about that the fact that the sun is setting almost
   directly in front of him.  The concept is reinforced by North
   American highways which are almost, but not quite, consistently
   labeled with logical rather than physical directions.  A similar
   situation exists at MIT: Route 128 (famous for the electronics
   industry that has grown up along it) is a 3-quarters circle
   surrounding Boston at a radius of 10 miles, terminating near the
   coastline at each end.  It would be most precise to describe the
   two directions along this highway as `clockwise' and
   `counterclockwise', but the road signs all say "north" and
   "south", respectively.  A hacker might describe these directions
   as `logical north' and `logical south', to indicate that they
   are conventional directions not corresponding to the usual
   denotation for those words.  (If you went logical south along the
   entire length of route 128, you would start out going northwest,
   curve around to the south, and finish headed due east, passing
   along one infamous stretch of pavement that is simultaneously route
   128 south and Interstate 93 north, and is signed as such!)