[Retros] On cylinder castling
lestourtereaux at free.fr
Sun Sep 8 14:36:18 EDT 2002
Greetings All !
The recent debate about cylindrical castling was quite entertaining. Let me
jump in. First, the problem I published can be found on
http://lestourtereaux.free.fr/chess/14.html . When I composed it, as Christian
said, I never thought that extended castling was possible. Why ? There are at
least two ways to define castling :
1. Explicitely, by stating that the king on e1 moves to g1/c1 and that the
rook on h1/a1 moves to f1/c1 if some conditions are satisfied.
2. Implicitely, by stating that the king moves two squares toward a rook
of the same color that hasnt move from its initial square and that the rook
jumps over the king, again if some conditions are satisfied.
For definition (1), extended castling on vertical cylinder is certainly not
natural, while for definition (2) it is. It seems that many composers consider
definition (2) to be valid for vertical cylinder chess.
Let us now consider horizontal cylinder boards. By definition (1), the are two
kinds of castling. However, definition (2) poses problem; since the initial
position is illegal, we could consider there is no such initial position and
that castling is impossible. I am pretty sure most composers will accept
castling in such a problem.
There are other fairy conditions which may lead to a debate. What about the
condition that a piece may move and check only if observed by another piece ?
White king e1, white rook h1 and black knight h2. May white castle ? Probably
no. Perhaps yes. Also, if there is n white pawns and more than 8-n white
fairy pieces in a direct mate, do we care that black has a last move since he
initial position is undefined ? Finally, can a paralysed rook be involved in
castling since it is usually considered as a king move ?
We get to the crucial point. There is an official set of rules for chess. There
is none for fairy chess; there is only a tradition. It is perfectly normal in
that case that there are some ideological debates.
If we come back to my published problem, the editor of StrateGems was in my
opinion awkward in dealing with the polemic. My problem can be corrected
(solutions with extended castling can be prevented) by changing slightly the
position of a single piece see my web site. The problem published as a
correction is not the correction, it is a variant on the same theme which I
found funny; using the extended castling the black king gets trapped in the h8
corner. This confusion is certainly unfortunate. As Christian, I do not
consider my original problem to be really cooked, however since it is extremely
easy to please everyone by moving one piece that I see no reason to not do it
P.S. When trying to define mathematically the rules of (fairy) chess I ran into
big problems. The board is defined without problems. But then a piece seems to
be defined by its moving abilities, which depend on the position, composed of
pieces on the board. I tried to circumvent the problem by naming pieces, but
this is possible only if the number of different pieces is countable, which I
think is not since it is basically an automorphism from the space of positions
to itself. I put everything aside thinking that I must be either mad or
insufficiently bright !
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