Pinned Knight Cannot Move

This question is based upon the rules of Chess and why I think they should be changed. It has to do with pinned knights, or more to the point, any pinned piece. 8/3k4/3R4/4r3/4N3/4K3/8/8 b KQkq - 0 1 Take for example a pinned knight. Who is protecting a Rook as well. I propose that whenever a piece is pinned, ie.. cannot move or their king would be mated, that whatever other pieces they are protecting can be taken by the opposing King. The rules say that the opposing king cannot take one of the protected pieces because that would be moving them into check. However, I believe a King should be able to take the 'protected' piece because the pinned piece is unable to protect their King and other pieces at the exact same time. That is why other pieces can take the so called 'protected' pieces. So why can't an opposing King take a 'protected' piece? Whar would happened if the rules changed to allow this?

 

Hmm.  Chess is a beautiful game as it is.

Still, it might be fun to experiment with some rule variations to see what would happen.

Many beginners have posted outraged threads about the stalemate rule and I think I understand pretty well why it is a necessary rule.

 

Who would lose their King first?

 

If you're allowed to move your king into a square attacked by a piece, i.e. moving into check, then why can't your opponent use the same option to expose their king to check by moving a pinned piece?

 

The rules have to be the same for both players.

Hi, unfortunately you haven't been clear. "Cannot move or their king would be mated" should mean what it implies, which is that there isn't an absolute pin. An absolute pin is when a piece cannot move according to the rules, because if it moved, the K would be in check. There's some sense to that, but quite simply, the rules have been decided upon, in such a way that the K is checked by a piece, even if it's in an absolute pin against its own K. If it isn't an absolute pin: for instance, a queen could be taken or maybe the King would be checkmated **after at least one more move by the opponent**, then that isn't an absolute pin and therefore it cannot apply to this question.

I think the OP's point is that the pinned Knight should not be able to give check, because it's not able to move. So taking the Rook would not be considered moving into check.

No idea what would happen it the rules were changed that way. Also no idea why that change should happen.

But unfortunately he didn't specify an absolute pin.

Let's just assume that because otherwise it doesn't make any sense.

 

I understood that distinction but don't think the idea is a logical one. If a king is allowed to move to a square that would normally be a normally allowed movement option for a pinned piece, then that opponent should be allowed to also open their king to attack by moving that piece to take the king off the board, ending the game.

 

You are correct. I am talking about an absolute pin. I propose that if a piece is absolutely pinned... cannot move otherwise the king would be in check, then any potential moves are invalid, as long as the absolute check exists. 

With black to move the king should be able to take the rook, because the white knight is powerless to move because it would cause the king to be in check.

The difference would be that the latter would be a normal check delivered by an unpinned piece. If you introduce the premise that a piece has to be able to move to deliver check, it looks consistent. Not that I particularly like the idea.

Thinking about it, there are probably edge cases with mutual absolute pins that actually make it confusing.

Now that I think about it, the above diagrams would not work, because as it has been pointed out, the one king is in check. This condition will not even happen so lets remove that from the thought experiment. Here is the condition I am talking about:

According to the current rules, what I propose breaks that rule, that a king cannot move into check. What I propose is that absolute pinned pieces cannot move, therefore any legal move that can be made by the piece involved in the absolute pin cannot be made until the absolute pin is removed.

If any piece is held in place(cannot move) by an absolute pin then the piece that is protecting the king loses its ability to make any move until the absolute pin is removed. 

In most cases this is implied because the absolute pin enables all other protected pieces to be taken without being taken by the pinned piece the next move. In only one condition is this implication not allowed to be implied and that is having the king of the opposing side take a piece that the pinned piece would otherwise have protected, had that piece not been absolutely pinned. That is why it is called "ABSOLUTE".

It's actually funny because you would be able to unpin a piece by pinning the pinning piece.

There is a logic to the rules as they stand. It would take another move for the opponent to take the piece that's pinned. So in a way, the rule change you propose would credit the opponent with being able to make an extra move.

This calls for finesse. 

This is certainly interesting because under the rule you propose, after black takes the rook, then white moves Kd4 to unpin the white K thus putting black into check, so black either takes the N with the rook, giving a draw, or moves the K to the only available square which protects the R, which is e6 and then white has some more checks, and you'd think the game would be drawn, as it seems to be under the normal rules.

 

#3 is enough to solve this supposed dilemma.

interesting idea

Black (to move) Ka3, Pa4, Rb4, Bb3

White Kb1, Ra1, Pa2 Qb2

Currently Black is mated.  With a rule change Black plays either ... Bxa2(not+) and white responds with Rxa2# or with Qxb4+ Kxb4+ (an interesting discovery), Rxa2 or black plays ... Bc2+, Kxc2+ Rxb2+, Kc3 Rxa2, Rxa2+ Kxa2, Kc2 and a draw.

 

I am guessing this is a rule change asked for by people who have lost because of a pinned piece still giving check, and once the rule change goes against them they will ask for it to be changed back.

     In the ancient warfare that was the model for the origin of chess, two monarchs were quarrelling over possession of a town or watershed or trade route or whatever. Kingdoms were considered the personal property of the king. In a battle, should a king be killed or captured, the quarrel was settled. For example, as recently as 1805 at the battle of Austerlitz, when the Russians and Austrians beat back the French attacks on both sides of the battlefield and started chasing them, Napoleon's hidden mass of troops overwhelmed the now-undermanned center position, destroyed the Russian Imperial Guards, captured Emperor Francis of Austria and sent Tsar Alexander of Russia fleeing for his life. The Russian and Austrian armies fled in panic and the war was won.

     Likewise in the position pictured here, should the black king capture the white rook, the white knight will kill the black king and the war will be over.