[Retros] Castling ambiguity officially resolved

Andrej Jakobcic Andrej.Jakobcic at guest.arnes.si
Mon Aug 23 07:34:58 EDT 2004

>>My point is: as a mathematician I am looking for right and good definition

of Position. I

>>think math definition is different from "chess rules definition (if any)".

>I think that is pretty unambiguous. And if an e.p. is illegal because it

would leave/put the

>player in check, then the pawn can't be captured by e.p. So the positions

are the same.

My opinion is that case is unambiguous but this way: after first move pawn
(at least theoretically) could be captured by e.p., later (even
theoretically!) couldn't ever be captured again. So the positions are NOT
the same.

>Francois Perruchaud points out that the International FIDE Arbiter Geurt

Gijssen has in the

>last few weeks made some modifications to the Laws of Chess. Since the Laws

are subject

>to arbiters' judgment (see Preface) this pretty much has the force of law.

As good arbiter as Gijssen is, himself can't modify FIDE rules. But his
formulation it is much better than FIDE:
Castling rights has been lost if:
a. if the king has already moved, or
b. with a rook that has already moved

In practical chess games that was usual interpretation of FIDE castling

Andrej Jakobcic

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