Suppose, for example, a player's Bishop is pinned (say, between his own
King and an opposing Rook). The Bishop thus cannot move, and
essentially it projects no power while it is pinned.

Can the opposing King move onto the pinned Bishop's diagonal?

Or, suppose a player blocks a check by moving his Knight (so the Knight
is pinned), but the Knight's new position (in theory) exerts power onto
a square occupied by the opposing King. Is the opponent in check?

My instinct tells me that a pinned piece cannot cause check, because it
could not actually play a part in the capture of the King. If the
piece becomes un-pinned (the player moves the king, etc) then it could
immediately place the opponent in check. But that's a guess...

Can anybody tell me the actual rule? Thanks!

--
David Filmer (http://DavidFilmer.com)

wrote:

Suppose, for example, a player's Bishop is pinned (say, between his own
King and an opposing Rook). The Bishop thus cannot move, and
essentially it projects no power while it is pinned.

Except the power to force an opponent to defend his King
from check.

Can the opposing King move onto the pinned Bishop's diagonal?

Not unless there is another man in between them.


Or, suppose a player blocks a check by moving his Knight (so the Knight
is pinned), but the Knight's new position (in theory) exerts power onto
a square occupied by the opposing King. Is the opponent in check?

Yes.


My instinct tells me that a pinned piece cannot cause check, because it
could not actually play a part in the capture of the King.

No piece may ever play a capture of the King in regular chess,
so this is not making any sense. You must get out of check,
and it makes no difference whether or not the checking man is
pinned, forked, skewered or all three.

If the
piece becomes un-pinned (the player moves the king, etc) then it could
immediately place the opponent in check. But that's a guess...

Can anybody tell me the actual rule? Thanks!

Yes, someone can.

The same thing applies to just-promoted pawns: the new
piece delivers check immediately, whether pinned or not.

Assuming your opponent has played a legal move, you
must immediately get out of check -- otherwise you are
checkmated or else you have replied with an illegal move.

The object of the game is to checkmate your opponent's
King, so it should come as no great surprise that King
safety cannot be ignored simply on account of a pin.

One of the drawbacks of chess is that not all its rules
are straightforward and intuitive. For example, suppose
I am playing a game at GetClub and have already
castled on the Kingside. Now a few moves later I take
a break and adjourn the game, to be resumed later.
Upon resumption, I note that I am (as usual) ahead in
material, but that as if by magic, my KR is back on h8,
where it had been before castling! My position is a bit
awkward now, since I am suddenly behind in development.
Do I steer my King toward e8 and clear the decks from
there to h8, so I can try castling again? Or do I write and
complain to Sanny *yet again*, risking that my antics will
result in forever being banned from GetClub, where I have
become -- according to the man himself -- a "star"? Ah,
what a dilemma. "Greatness" has its price. ;D

-- help bot

One of the drawbacks of chess is that not all its rules
are straightforward and intuitive. For example, suppose
I am playing a game at GetClub and have already
castled on the Kingside. Now a few moves later I take
a break and adjourn the game, to be resumed later.
Upon resumption, I note that I am (as usual) ahead in
material, but that as if by magic, my KR is back on h8,
where it had been before castling! My position is a bit
awkward now, since I am suddenly behind in development.
Do I steer my King toward e8 and clear the decks from
there to h8, so I can try castling again? Or do I write and
complain to Sanny *yet again*, risking that my antics will
result in forever being banned from GetClub, where I have
become -- according to the man himself -- a "star"? Ah,
what a dilemma. "Greatness" has its price. ;D


This is not the drawback of chess, simply the drawback of "GetClub".

A pinned piece such as a bishop can definitely deliver check while it
is pinned. Think of it another way: Imagine that the object of the
game is to capture the opponent's king. If this were the case, then
there could be no such thing as a piece being pinned by the rules of
the game. It might be 'pinned' in the sense that a smart player would
know not to move it, but it would still be legal to move it. If you
did that, then you would capture your opponent's king immediately
before he has a chance to capture yours.

Modern chess provides that the king is not actually captured - the game
ends one move before that happens.

wrote:
Suppose, for example, a player's Bishop is pinned (say, between his own
King and an opposing Rook). The Bishop thus cannot move, and
essentially it projects no power while it is pinned.

Can the opposing King move onto the pinned Bishop's diagonal?

Or, suppose a player blocks a check by moving his Knight (so the Knight
is pinned), but the Knight's new position (in theory) exerts power onto
a square occupied by the opposing King. Is the opponent in check?

My instinct tells me that a pinned piece cannot cause check, because it
could not actually play a part in the capture of the King. If the
piece becomes un-pinned (the player moves the king, etc) then it could
immediately place the opponent in check. But that's a guess...

Can anybody tell me the actual rule? Thanks!

--
David Filmer (http://DavidFilmer.com)

Shijith wrote:

One of the drawbacks of chess is that not all its rules
are straightforward and intuitive. For example, suppose
I am playing a game at GetClub and have already
castled on the Kingside. Now a few moves later I take
a break and adjourn the game, to be resumed later.
Upon resumption, I note that I am (as usual) ahead in
material, but that as if by magic, my KR is back on h8,
where it had been before castling! My position is a bit
awkward now, since I am suddenly behind in development.
Do I steer my King toward e8 and clear the decks from
there to h8, so I can try castling again? Or do I write and
complain to Sanny *yet again*, risking that my antics will
result in forever being banned from GetClub, where I have
become -- according to the man himself -- a "star"? Ah,
what a dilemma. "Greatness" has its price. ;D


This is not the drawback of chess, simply the drawback of "GetClub".

Right. You must have missed my winking smiley. Of
course I will not clear the decks just to try and see if the
program will allow me to castle once more -- that would
be silly (and take around a week to accomplish, if not
longer). Regulars will note that in spite of my going
easy on Sanny -- at least in comparison to his bitter
enemies -- I am one of the most frequent critics of this
program's many flaws.

--------

Not all the rules of chess are intuitive. For example,
castling *through* check could have been legal or not,
based on a majority vote. Obviously, the King which
passes through check cannot actually be captured, as
it is not the opponent's move until after this move has
been completed. Once completed, the King is in no
danger of capture, so this was an arbitrary decision.
The same thing applies -- even today -- regarding touch
move. The USCF, for instance, frequently "revises" its
interpretations and rules on what this means in practice,
depending on the latest round of complaints.

Yet as far as I know, the pinned man (yes, a pawn can
be pinned just as well as pieces) has for centuries effected
check on the King despite being pinned.
I have played several opponents who were fairly good, yet
who nevertheless lacked a basic understanding of the
technical rules, such as this. A quick glance at the
rulebook reveals a boring, repetitive style of prose, which
tends to discourage extensive study. Bot it didn't stop me!
:D

-- help bot

It could be understood as follows.

The first person to kill opponents king is the winner. King can not be
exchanged.

In case of pin if you bring king where Bishop can give Check. The
Bishop will kills the King and win despite being pinned between it's
king as Bishop will be the first to Take the King.

Bye
Sanny

Play Chess at: http://www.GetClub.com/Chess.html

Sanny wrote:
It could be understood as follows.

The first person to kill opponents king is the winner. King can not be
exchanged.

In case of pin if you bring king where Bishop can give Check. The
Bishop will kills the King and win despite being pinned between it's
king as Bishop will be the first to Take the King.


If I am not mistaken, this is precisely the same style of
prose as to be found in the aforementioned "rules of chess".
Is it any wonder, then, that no one seems to have actually
read the horrid tome? I rest my case.

-- help bot

wrote in message
ups.com...
Suppose, for example, a player's Bishop is pinned (say, between his own
King and an opposing Rook). The Bishop thus cannot move, and
essentially it projects no power while it is pinned.

Can the opposing King move onto the pinned Bishop's diagonal?

Or, suppose a player blocks a check by moving his Knight (so the Knight
is pinned), but the Knight's new position (in theory) exerts power onto
a square occupied by the opposing King. Is the opponent in check?

My instinct tells me that a pinned piece cannot cause check, because it
could not actually play a part in the capture of the King. If the
piece becomes un-pinned (the player moves the king, etc) then it could
immediately place the opponent in check. But that's a guess...

Can anybody tell me the actual rule? Thanks!


As others have pointed out, a pinned piece can indeed cause check, the
actual rule is "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."

The rules of chess can be found he
http://www.fide.com/official/handbook.asp?level=EE101 and the above quote
is from 3.8.

Regards,
Arfur

wrote:
Suppose, for example, a player's Bishop is pinned (say, between his own
King and an opposing Rook). The Bishop thus cannot move, and
essentially it projects no power while it is pinned.

Can the opposing King move onto the pinned Bishop's diagonal?

no


Or, suppose a player blocks a check by moving his Knight (so the Knight
is pinned), but the Knight's new position (in theory) exerts power onto
a square occupied by the opposing King. Is the opponent in check?

yes


My instinct tells me that a pinned piece cannot cause check, because it
could not actually play a part in the capture of the King. If the
piece becomes un-pinned (the player moves the king, etc) then it could
immediately place the opponent in check. But that's a guess...

Your instinct guessed wrong.


Can anybody tell me the actual rule? Thanks!

Have you considered purchasing a rulebook?




--
Kenneth Sloan
Computer and Information Sciences +1-205-932-2213
University of Alabama at Birmingham FAX +1-205-934-5473
Birmingham, AL 35294-1170 http://www.cis.uab.edu/sloan/

Sanny wrote:
It could be understood as follows.

The first person to kill opponents king is the winner. King can not be
exchanged.

In case of pin if you bring king where Bishop can give Check. The
Bishop will kills the King and win despite being pinned between it's
king as Bishop will be the first to Take the King.

Bye
Sanny

Play Chess at: http://www.GetClub.com/Chess.html




Now I understand why your program plays so badly (and so slowly).

--
Kenneth Sloan
Computer and Information Sciences +1-205-932-2213
University of Alabama at Birmingham FAX +1-205-934-5473
Birmingham, AL 35294-1170 http://www.cis.uab.edu/sloan/