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GameKnot related: Absolute Pin?
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shotgunblast2dfc
01-Mar-12, 18:40

Absolute Pin?
Can a king ever attack a piece if it will put the attacking King in check? ? What if the piece that would attack the king once the king captured the covered piece is acting as a cover piece preventing the defending king from going into check?
rockall
01-Mar-12, 21:44

No
A king can never move into check, even if the piece attacking the square is pinned.
rockall
01-Mar-12, 21:48

FIDE rule 3.9
"3.9
The king is said to be 'in check' if it is attacked by one or more of the opponent's pieces, even if such pieces are
constrained from moving to that square because they would then leave or place their own king in check. No piece
can be moved that will either expose the king of the same colour to check or leave that king in check."
www.fide.com
baronderkilt
03-Mar-12, 01:47

That is
an interesting and understandable question, answered by rockall. So I just want to expand to the next question one might ask ...



Here if WT can only play Kb3 it gives MATE ! But alas, he cannot move his king to the square attacked by the Black Queen. Notice, even if there were a black piece on b3 which would be captured by the WT King, that can make no difference.

Sometimes it helps to think of the situation as if playing blitz on a real set rather than online. And in those games Kings can be taken. In a regular game it can be asked Which King would be TAKEN FIRST? If the could be taken. Whoever could be Taken First, simply cannot go there. And there are No Mitigating factors.

If it Did happen that a King went into check during a live tournament game, otb, either player could point it out later and the game would need reinstated back to the position just prior to the illegal move, and a different move made. It cannot be done if the game concluded without it being noticed and claimed to the TD, however.

Of course in my position above one might ask "But does not Kb3# end the game, since Mate ends the game!". Well these are the things that give Directors nightmares. lol. Ordinarily yes Mate ends the game, the instant the piece was released on the mating square, without regard to a punching of the clock in time. As I understand it, correct me if that has changed, someone.
I believe what would have to be done in such case would be view the illegal Mate as requiring acceptance by the "mated", who would otherwise be considered to be "On the Move" and therefor able to make Claims. Thus can make an Illegal Move Claim requiring retraction of the illegal move that would have otherwise been a mate.

That is my perspective from my 1990's USCF directing. So I dont know if present USCF or FIDE Rules might address such a thing clearly and precisely now ... But if you ever find yourself playing a tournament in the 1990's .... well now you know. lol.

(I hope I get a chance to look it up online tho. Sounds interesting.)  
baronderkilt
03-Mar-12, 01:51

YES Thank You Rockall ...
We can see Article 5.1 FIDE from his link to FIDE Rules, does address it very specifically, as follows:

5.1 The game is won by the player who has checkmated his opponent’s king. This immediately ends the game, provided that the move producing the checkmate position was a legal move.
shotgunblast2dfc
05-Mar-12, 08:58

Deleted by shotgunblast2dfc on 05-Mar-12, 09:04.
shotgunblast2dfc
05-Mar-12, 09:04

thank you so much..
to all that answered.. You are the bomb.. would such a move be allowed here on gameknot? i resigned a game i was winning because i second guessed my strategy, and would have allowed my rook to be taken by my opponents king that rook was covered by a bishop that was blocking my opponents queen from having me in check. The exchange was very much in my favor but i am confident my opponent was counting on his ability to take my rook with his king to change the flavor of the exchange on his end... i am sorry now that I did such a foolish thing.. I am very passionate about playing flawless games (which I very rarely do) if I make foolish blunders then I automatically forfeit the game and allow my injured pride to turn my loss into a great lesson..
rockall
05-Mar-12, 13:11

shotgun
I have not tried your particular example, but GK's programing limits you to legal moves, and is good at it. I have
a high degree of confidence the GK software will not allow you to move your king into check. I would be
interested if anyone has a contrary example.

Yes, it often makes sense to resign if you are far behind in material, but sometimes it is worthwhile to continue
playing for a time. If your opponent is good, then you can learn from the manner in which he takes advantage of
his material advantage. If your opponent is not very good, then you might treat it as a game in which you have
given a handicap and must battle back. You might also want to consider the possibility that your opponent's
material advantage is not meaningful. Do you have an attack going that can win the game?

Are your pieces fully developed while some of his pieces are still sitting undeveloped on the back rank, because
he made the mistake of moving his queen or one of his knights three or four times in the opening while you were
developing all of your pieces at the earliest opportunity? This situation is very common among beginners, and if
you move promptly to take advantage of it, your material disadvantage may be unimportant.