From: Tom Bombadil <bombadil <at> NMAA <dot> ORG>
Date: 21 nov 1996
Subject: Re: Basic Rules of Shogi

I like Sam Sloan's rendition of the Shogi rules.
George F.'s comments are useful and fix some misleading ideas.
I think these points need to be spelled out more rigorously, though.
Two thoughts.

I think George's point about promotions can be clarified and added
like this:

1) Unlike the other pieces, the R, B, & P's promotions only increase =
their mobility and do not decrease any of the moving options, i.e., the =
set of move options for unpromoted R, B, or P is always a proper subset =
of the set of the set of move options for a promoted one.
2) Therefore, these pieces in should be promoted when possible, except =
for just those cases in which having less mobility and fewer squares =
attacked can potentially be advantageous.
3) Such cases exist.  The rule prohibiting a pawn drop for checkmate =
creates such exceptions, in which case declining a promotion may either =
allow or prevent an otherwise illegal pawn drop.  These situations are =
very common in Shogi problems.=20
4) In chess, the analog to this would be an underpromotion of P to B or =
R instead of Queen to avoid stalemate.

As for 'material advantage':
Sam writes that 'it doesn't mean much at all.'  Clearly this is =
blatantly false, otherwise the handicap system would be meaningless.  =
George adds that it is important in the opening.

As I see it, there are two types of variables, static and dynamic.  =
Material is static; space and time are dynamic.  In chess, the static =
variables (material and pawn structure) are more important than in =
Shogi.  Even in cases where one trades static for dynamic advantage =
(e.g., a gambit or sacrifice), the goal in chess is usually to cash in =
the dynamic advantage and get your material back with interest.  In =
chess, creating a materially won endgame, e.g., creating a passed pawn, =
is implemented more often than directly assaulting the opponents king =
for checkmate.  The exception is the mating sacrifice.

In Shogi, the dynamic elements carry much more weight than in chess.   =
This increases as the game gets farther advanced, as George points out.  =
 In the endgame, in fact, sacrificing material for mate is the rule and =
not the exception.  Another variable to look at is the pace of the game. =
 Material will play more of a factor in a slow-paced game than it will =
in a fast-paced game, which tends to favor the side with a dynamic =
advantage.   Since the opening starts rather slowly, this is another =
reason that material is very important in the beginning of the game.  =20

-Tom Eigelsbach