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A way to view the 50-move rule?

#1

I was thinking about it, and some conclusion came to mind:

Every position since the last capture or pawn move, and none before those, can be reconstructed by means of legal moves.

That is, when a game meets the 50-move rule, it means no definite change has happened within the last 50 moves, and within those only.

But I think my conclusion might not always be right, because it's technically possible that a sequence of legal moves can't avoid ending in checkmate. For example, a check situation in which the only legal move is to take the checking piece and deliver checkmate at the same time.

I was thinking about it, and some conclusion came to mind: Every position since the last capture or pawn move, and none before those, can be reconstructed by means of legal moves. That is, when a game meets the 50-move rule, it means no definite change has happened within the last 50 moves, and within those only. But I think my conclusion might not always be right, because it's technically possible that a sequence of legal moves can't avoid ending in checkmate. For example, a check situation in which the only legal move is to take the checking piece and deliver checkmate at the same time.
#2

One could consider changing the 50-move-rule in such a way that 50 consecutive "reversible" moves would be needed for the game to be drawn. (With a move being "reversible" if the position before that move could still be reached by a series of legal moves.) That would exclude the example you gave.
Not sure how much of a difference it would make anyway. (Also, it might be difficult to identify "reversible" / "irreversible" moves as it might not always be so clear as it is in your example.)

Btw, trying the same kind of rule in crazyhouse would have the funny effect that every game would be automatically drawn by move 50...

One could consider changing the 50-move-rule in such a way that 50 consecutive "reversible" moves would be needed for the game to be drawn. (With a move being "reversible" if the position before that move could still be reached by a series of legal moves.) That would exclude the example you gave. Not sure how much of a difference it would make anyway. (Also, it might be difficult to identify "reversible" / "irreversible" moves as it might not always be so clear as it is in your example.) Btw, trying the same kind of rule in crazyhouse would have the funny effect that every game would be automatically drawn by move 50...
#3

I like the idea of considering a change in the rule, but yeah, "reversible"/"irreversible" is not a very clear matter... In fact, sometimes the only legal continuation(s) will have a piece taken or even a forced pawn move, which would reset the count after the 50-move-ruling point.

A simple case problem is when the 50th move without capture or pawn move is a check that can only be met with capture (regardless of the mate in the example I gave originally).

And you are right about crazyhouse, haha.

I like the idea of considering a change in the rule, but yeah, "reversible"/"irreversible" is not a very clear matter... In fact, sometimes the only legal continuation(s) will have a piece taken or even a forced pawn move, which would reset the count after the 50-move-ruling point. A simple case problem is when the 50th move without capture or pawn move is a check that can only be met with capture (regardless of the mate in the example I gave originally). And you are right about crazyhouse, haha.
#4

I like this idea. This would also include things like first king moves resetting the 50-moves-timer because they take away the castling-right and are thus non-reversible.

I like this idea. This would also include things like first king moves resetting the 50-moves-timer because they take away the castling-right and are thus non-reversible.
#5

Thre rules of chess dont need changed. They need left alone forever. WTF

Thre rules of chess dont need changed. They need left alone forever. WTF
#6

@GMScuzzBall Minor changes do happen. We've just recently had a change in the game result rules regarding time-out. You used to get a draw if your opponent timed out and you had the classical "insufficient material", but now you get a win if there's any possible continuation leading to mate.

Similarly, the proposal here is: the game is declared a draw if there's any possible continuation leading to the position 50 moves ago. Which is very similar to the current 50-move rule, except for some rare cases in which EVERY legal continuation has a capture or pawn move or checkmate. (Not to be confused with forced mate, because the winning side may very well not go for it.)

@GMScuzzBall Minor changes do happen. We've just recently had a change in the game result rules regarding time-out. You used to get a draw if your opponent timed out and you had the classical "insufficient material", but now you get a win if there's any possible continuation leading to mate. Similarly, the proposal here is: the game is declared a draw if there's any possible continuation leading to the position 50 moves ago. Which is very similar to the current 50-move rule, except for some rare cases in which EVERY legal continuation has a capture or pawn move or checkmate. (Not to be confused with forced mate, because the winning side may very well not go for it.)

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