A Former Loophole-The “Legal” Triple Check

[David Sedgwick]

Yeah, but it's possible that the months question is a poor comparison. We know all the months have at least 28 days, and that when one asks "which month has 28 days" they are either seeking the answer "February" or asking a trick question. We also know that nobody intended to frame the Laws of Chess such that we could escape check by moving into three simultaneous checks, because it would be ludicrously silly.

Obviously, if an arbiter had been called to the board after 3. g7+, there could have been only one possible answer, even before the Thurlow amendment to the Laws.

Nevertheless, I agree with Rewan that it is a lovely gem. That was not the view of the young Polgar sisters.

The study does seem to polarise opinion a lot. Some are amused and impressed, others just think it stupid.

Anyway, welcome to the Forum, Rewan

[Geoff Chandler]

Recall reading about this jokey one from a very old BCM.

6RK/8/7k/8/6Pp/7P/8/8 w - - 0 1

White has just played g2-g4 and Black claimed stalemate.

White pointed out the en passant capture.

Black said the rules say it is only an option, therefore it's a choice, and I choose not too!

[Matt Mackenzie]

Weren't the Laws changed in that instance too, to make it clear you had to capture en passant if it is the only legal move?

[E Michael White]

I expect quadruple and higher checks are possible too. Will think about it unless someone else does it first.

The average number of days in September over the last 300 years is not 30.

[Alex McFarlane]

I expect quadruple and higher checks are possible too. Will think about it unless someone else does it first.

The average number of days in September over the last 250 years is not 30.

While singing a Gregorian chant I have a legal position in which the king moves into check from 9 pieces. Without previous pawn promotion I think that is the maximum.

[E Michael White]

I guess that's right. The other Bishop is clearly conducting your singing.

Lets hope the Gregorian chant you were practising was not the famous "He who Dwells" which could be a disaster in Blitz chess.

[David Sedgwick]

The average number of days in September over the last 300 years is not 30.

Is it 29.96?

[E Michael White]

Yes well done; I think that's correct. Gosh our senior arbiters are sharp (#) tonight. Not only do they solve the problems but encode a reply which demonstrates they have without spoiling the puzzle for others. Question is would the Polgars like the extended problems?

I can think of a few more which may or may not be possible:-

1. octochecking with 8 knights (promotions allowed) . This might be difficult working the king into position avoiding the other knight checks to satisfy the legal position bit. (9 or 10 knights would not work)
2. maximum number of queen multi checks (promotions allowed)
3. maximum number of multi checks any combination of pieces ( promotions allowed)

[Nick Ivell]

Silly question if I may.

I take it that if I deliver double check and the opposing king can't move, that ends the game in all cases? There can never be a defence by capture?

I seem to recall Nimzowitsch writing that when faced with double check, even the most timid king must scuttle...

[Matthew Turner]

So there are three ways out of check, take, block or run. If it is double check then you cannot take off both pieces. The checks most come from different direction, so you cannot block, so yep it is just run left.

[Paolo Casaschi]

The old versions of the FIDE rules of chess said that, regarding check, “The king is in check when the square it occupies is attacked by one or two of the opponent’s pieces.” This left an a potentional ambiguity-if the king was left attacked by three pieces then it was not in technically in check-it was is left in a “legal” triple check.

If you want to be really really pedantic you might want to point out that, even in the case of a triple-check it is still true that "one of the opponent's pieces attacks the king's square". The fact that two other pieces attacks the same square does not invalidate that. It does not say "by one or two but no more than two".

[Kevin Thurlow]

Actually, FIDE did foul it up as it previously said "one or more", then they changed it to "one or two", before changing it back.

And if it said "one or two" then "three" does invalidate the Law. Laws need to be clear, and if you are arguing about what they mean, then they are not clear.

[MJMcCready]

There have been problems inspired by another previous "loophole" of the Laws - they never originally specified that you had to promote a pawn to a piece of the *same* colour. Of course, the spoilsports at FIDE have now fixed that one as well.

That's curious. I didn't know that. I wonder if anyone has promoted to another colour. I suppose there could be positions where an underpromotion of that nature might be beneficial if it means that the promotion blocks a check and thus cannot be captured by the opponent.

[MJMcCready]

Are we certain check in triplicate is as far as it goes? A quadruple check doesn't exist or does it?

[John McKenna]

Nonuple already -

I expect quadruple and higher checks are possible too. Will think about it unless someone else does it first.

The average number of days in September over the last 250 years is not 30.

While singing a Gregorian chant I have a legal position in which the king moves into check from 9 pieces. Without previous pawn promotion I think that is the maximum.