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Constitutional Characters. A systematic set of names for Major and Minor pieces.[All Comments] [Add Comment or Rating]

Tony Paletta wrote on Sat, Dec 13, 2003 03:15 PM UTC:

Charles,

While dictionary definitions provide a rough guide to the meaning of words
have, they (of course) only tell us part of the story. Case in point: Why
are the Rooks commonly said to move orthogonally when a Bishop's lines of
movement are also in orthogonal directions? 

One historic and important role of orthogonal lines in mathematics and its
applications is in the measuring of distance. While the King may have the
title, the Wazir is the natural 'ruler' of the chessboard. Start on c1,
move up three Wazir moves, then four Wazir units to the right to g4 and
(using the Pythagorean theorem) you can calculate that you are five
'Wazir units' away from your starting point. This also works with a
'Ferz' -- but on one color only (from c1 three Ferz units NE, four Ferz
units NW puts you at b8, five 'Ferz units' from the starting point).    
 

So both the Wazir or Ferz could be used to measure (Euclidean) distances.
The difference is the Wazir directly measures ALL the whole unit distances
that come up in talking about the square grid of the chessboard. So it
probably was more natural to think of the Wazir/Rook as THE orthogonal
directions on the chessboard.

Of course this isn't 'the way it happened' and it isn't the only way
it could have turned out based on the dictionary definitions, but the
convention for usage is not paradoxical, contradictory or especially
confusing.