From: Pieter Stouten <stoutepf <at> CHEMSCI5 <dot> dmpc <dot> com>
Date: 8 oct 1995
Subject: Re: King in check

At 14:38 95/10/08, Jeff Mallett wrote:

>Note that if you're taking your definition of "stalemate" from the world of
>chess, they are identical.
>
Part of the word "stalemate" implies that there is a mate (albeit reached
via a route that is not considered legal in chess (i.e., a player moving
her/his own king into check)). When one has no legal moves whatsoever, but
is not in check or mate, it cannot be called stalemate. Also, I do not
think that the definitions of stalemate and having no possible moves are
the same in chess. I think the second concept is unknown there, but I
really am not qualified to say anything about chess.

>In chess, stalemate simply means that "the
>player cannot make any legal move" [USCF Rule I.12.C].  A move that puts
>your king in check and a move that causes a piece to make a half-twist
>spiral around the board while simultaneously capturing all the opponent's
>pieces at once are both equally illegal, i.e. 100%.
>
I am not sure I understand the point you want to make. The logical
consequence of [ transfering the above chess rule to Shogi .AND. taking
into account that stalemate is legal in Shogi ] is that not being able to
make legal moves (i.e., only able to make illegal moves) is legal in Shogi.
I am not sure what the consequences of this conclusion are, though. Apart
from that, if one has no moves, one cannot make any legal or illegal moves
(disregarding what I would call impossible moves such as the spiral move
you describe).

>As for whether stalemate should be a win or draw, you can pick whatever
>rule you like.
>
> [...]
>
>I don't believe it's too pedantic to require that the rules for a game
>should cover ALL possible positions of the game, not just the ones
>reachable by reasonable play.
>
I do not think it is pedantic, although it is a truism that any rule will
be abused. I would think that when a player cannot make any move (this is
NOT stalemate, as that concept is unknown in Shogi), the game is over
(unless you want to allow a player to pass). As to the question who wins in
such a case, one can pick whatever rule one likes.

There are real life cases that are more problematic than the no-move
problem. E.g. when both kings have escaped, but one (or both) player does
not want to start moving all her/his pieces into the promotion zone because
1) they would lose pieces, or 2) they would lose by counting, then the rule
of thumb is that counting will happen anyway when neither player can mate
the other. The player who does not want to resort to counting can of course
always claim he has still mating potential. What to do in those cases? Go
to your local Shogi authority and let him decide <g>?

Cheers, Pieter.

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Pieter Stouten                              ||  Nothing shocks me;
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