The hardest chess problem in the world?

This article was the second post for the Hebden Bridge Chess Club blog by the Duchess of Blunderboro. It was published in February 2011 and at the time of writing it is one of the most viewed posts on the website.

Hebden Bridge Chess Club members will be well acquainted with my passion for digging up chess curiosities from across the ‘interweb’. Recently I came across the perplexing puzzle below. It’s White to play and mate in 1.


White to play and mate in 1

Yes, in 1! Try putting that one through your computer and it will fry it’s chips before it finds the answer. If I told you that the solution is a VERY unusual move that is no longer strictly within the bounds of the rules of the game then that might help you a little bit. The solution will be revealed at the bottom of this post.

Anyway, the legend around this particular problem is shrouded in mystery. No-one knows who composed it, nor do they know when, but it is evident that this puzzle pre-dates the publication of FIDE’s official rules of the game (another little clue there).

As usual, I was not satisfied with this lack of provenance and so, having tried to cultivate a lead from the internet and failed, I turned to this blog’s old friend and oracle on chess history, Lady Cynthia the Duchess of Blunderboro, to see if she might be able to provide me with a clue. So, last week I sent her an instant message with the problem attached. Here is how our chat developed:

Intermezzo: Hi Duchess. Any idea who composed this problem?

Duchess: Oh yes! That is one of Grandfather's. It’s a funny story actually.

Intermezzo: Wow! Care to elaborate for me? How about a blog post?

Duchess: Certainly!

So, without further ado, I’ll hand over to Lady Cynthia, who will explain all.

The Duchess of Blunderboro

“I first encountered this position in June 1937 when I was 15 years old. It was a warm summer’s day. I had taken my chess set out to the conservatory and was thumbing through one of my Grandfathers old score books in a bid to convince my Father that I was taking my chess education seriously. I had idly played through several games without taking too much time to consider the ideas behind the moves when I reached the final stages of the game in which the position in question appeared. Noticing that the game lasted only a few moves more I paused for a moment to visualise them as I couldn’t be bothered to play them out over the board. As I did this a voice from just behind me said “There’s an amusing story behind that position”.

Jumping with the shock of the sudden interruption, I turned to see that Daddy had sneaked up behind me and was smiling at the recollection of some long distant memory. “It looks like a perfectly straightforward position to me. Black should really have resigned long ago” I observed a little put out that I was being spied upon.

“I’d have to agree with you,” said my Father as he moved round the table to sit down opposite me. “But how about if I told you that Granddad had missed a very unusual and extremely witty mate in one in this very position?”

A cursory glance at the board told me that there was no such mate in one. “Impossible!” I announced, "There is no way for White to mate in one move, even by some such sneaky means as an under promotion.”

“Again, I agree with you,” my Father beamed back, “and so did Granddad. But when you’ve been told that there is a mate in one by non-other than the great Adolf Anderssen, you have to take it seriously.”

“What? “ I spluttered. “Anderssen saw this game and found mate in one?”

The Cafe de la Regence

“Indeed he did,” confirmed my Father. “Your Granddad played this game in Paris at the Café de la Regence in 1878. It was a casual game against a fellow of no particular consequence but, as was his habit in those days, he recorded the score so that he could study the game at a later date. It just so happened that there was a big international tournament taking place in Paris at that time and consequently several of the world’s best were taking their leisure in the café which was renowned as a venue for chess playing. Anderssen, who was nearly 60 years old at that point and competing in what turned out to be his last tournament, happened to be one of small group kibitzing Granddad’s game right at it’s very end and had had a joke with him at it’s conclusion saying,

Adolf Anderssen in later life

“Did you know that you missed a very amusing check mate in one a couple of moves before the end?”

Your Granddad had been dumbstruck as he well knew who Anderssen was but was totally convinced that no such mate existed so he didn’t know how to respond. Anderssen had quickly set up the crucial position on the board again and then said.

“The solution really is most unusual. In fact I’d say it would make a striking problem. Check mate in one move. Can you find it?”

Your Granddad told me that he, his opponent and the growing group of kibitzers stared in stunned silence for a couple of minutes trying to find the answer. After a while it became evident that they couldn’t do it so, quietly, Anderssen reached across the board and pushed the White pawn to b8. He then picked it up and replaced with… a black knight!”

As he said these words my Father replicated the great man’s actions, under promoting the pawn to a black knight. He chuckled merrily as he did so. I starred open mouthed in amazement for it was, undeniably, checkmate.

1. b8=N (black) and check mate!

“But, surely that’s illegal,” I stammered.

“Yet again, I must agree with you,” laughed my Father. “But in fact, at the time this game was played there was no specific rule stating that a pawn had to be promoted to a piece of the same colour!"

So, this then is the story behind the position which has since become known as a chess problem of unknown origin. For myself I like to think that the origin was Anderssen himself for he was a renowned composer of chess problems and had said himself that the position would have made a striking puzzle. Being as he died not long after the Paris tournament I often imagine that this position might have been found amongst his documents after he died unpublished and uncredited. This is fanciful of me perhaps, but it's plausible.”

Thanks, as ever, go to the Duchess for bringing us this 'exclusive' story. As a final note on this, the hardest of chess problems, I should add that FIDE’s official rules now require that a pawn reaching the eighth rank must promote to a piece of the same colour.

The French, fried!

"I see you stand like greyhounds in the slips,
Straining upon the start. The game's afoot:
Follow your spirit; and, upon this charge
Cry 'God for Harry! England and Saint George!'"

- from 'Henry V' by William Shakespeare

Readers who are not medieval historians may not be aware that the 15th of October is a truly auspicious date for Englishmen. This year the 15th of October was the 596th anniversary of the Battle of Agincourt where Henry V’s English army took on a numerically superior force of Frenchmen and absolutely thrashed them. With the black pieces too!

This year the anniversary was leant added poignancy by the fact that, on Saturday, Wales played France in the Semi-Final of the Rugby World Cup in New Zealand. As I watched the brave men of Wales, losing gallantly on this occasion, I couldn't help thinking how ironic it was that this fixture should have been played on the 15th of October. In 1415 it was, not just the English, but primarily the renowned longbow men of Wales who were instrumental in helping good king Harry defeat the French knights on away soil.

Today then, in commemoration of the stout Welshmen who fought the French on two battle fields nearly 600 years apart, I would like to offer another thrashing of the French. This time on the chess board.

D.Shapland  vs. D.Heron

(C06) French Defence: Tarrasch Variation 

Wandering Dragons Club Championship,

Edinburgh,

17th of November, 1998

	A	B	C	D	E	F	G	H
8									8
7									7
6									6
5									5
4									4
3									3
2									2
1									1
	A	B	C	D	E	F	G	H

Shapland, D. 103 - Heron, D. 161

1-0 (Wandering Dragons Club Championship) 17/03/1998

[#] 1.e4 I mentioned my time living in Edinburgh and playing chess at the "Wandering Dragons" club in a previous post "An Equine Tribute". This game was played as part of the club's own championship which was held annually and progressed at a sedate pace over the course of the league season on nights when there were no fixtures. 1...e6 For the first time on this blog here is a French Defence. It will make regular reappearances as it is such a popular reposnse to 1.e4. This is the opening that Wilhelm Steinitz famously claimed to be "the dullest of all". For many years I would have tended to agree with him because I used to hate playing against the French. I simply couldn't find a system that I liked playing with the White pieces. For quite some time I floundered around pretty badly until eventually I settled on the Tarrasch variation and committed myself to familiarising myself with it's strategic and tactical themes. Since I made the effort to do this I have found that I rather enjoy playing some of the main lines of this variation and indeed, the reader will find quite a number of games against the French on this site from this point forwards. This game, more than any other, was the one that changed my negative perceptions of White's possibilities against the French Defence. 2.d4 d5 3.Nd2 This move is the signature move of the Tarrasch variation. White develops his queen's knight in such a way as to avoid having it pinned after 3.Nc3 Bb4 (the Winawer variation) and indicates his willingness to try and support his strong central pawns by leaving the c3 square available for his c-pawn to occupy. This method of development can sometimes cause White difficulties as his pieces strive to activate themselves harmoniously but, this is a secondary concern compared to the objective of taking and holding a dominant space advantage in the centre of the board. 3...Nf6 This is the "closed" variation of the Tarrasch. With this move Black indicates that he is prepared to accept a slightly cramped position in order to lure White's pawns to squares on which they are more susceptable to a counter attack. Black will surrender the centre to White's pawns and then attempt to undermine them as the game develops. The other frequently employed method for Black to employ against the Tarrasch is the "open" system which involves playing 3...c5 at once. This forces early pawn exchanges in the centre which succeed in dissolving White's spacial advantage but allow him instead to develop his pieces quite actively and rapidly. As always with openings it is a matter of personal taste with each exponent trying to direct the game down an avenue that they will feel most comfortable playing. 4.e5 White accepts the bait and takes the central space that Black has offered him. Into the bargain he also gains a tempo on the Black knight which will now have to relocate. 4...Nfd7 5.Bd3 c5 Black begins his counter measures. From c5 this Black pawn aims to undermine White's pawn on d4 and, indirectly therefore, also the pawn on e5. 6.c3 Nc6 7.Ne2 It may seem odd to develop the king's knight here but White is preparing for Black to add further pressure to d4 by putting his queen on b6. In such an eventuality it is important for White to be able to play Nd2-f3. As we can see the d4 square is pivotal to the battle at this early stage of the game. 7...cxd4 Another viable option here for Black is to maintain the tension in the centre for the moment and heap up pressure on d4 by playing 7...Qb6. I've faced this line several times before and will be posting games in this line here in future. 8.cxd4 f6 The second part of Black's plan to undermine the White pawn centre now comes into play. Having weakened the d4 pawn by exchanging on that square Black now attacks the pawn on e5. White can't support e5 so he must either exchange pawns on f6 or play a gambit line. 9.exf6 This was my choice (and it is the mainline choice) in this variation for a number of years. More recently I have unearthed and prepared a sharper alternative (9.Nf4!?) which has served me well and provided me with a great deal of fun and some very interesting games. 9...Qxf6!? An interesting choice from my colleague. Most of the time Black plays 9...Nxf6 here. The concept behind this move is to immediately put pressure on the d4 square again. Black is also preparing for the third part of his strategy in this variation which is to play e5. The down side to this move (as Lev Psakhis points out in his wonderful bible of a book on the Tarrasch variation) is that the queen can become vulnerable to a counterattack from the White pieces on this square. 10.Nf3 h6 Black prevents his opponent from playing 11.Bg5 which of course is highly desirable. This may be in keeping with his strategy but the downside is a further weakening of his king's side pawn structure. 11.O-O Bd6 This is still all straight out of the opening book. Black's plan is to castle short and then play e5. If he succeeds in doing this then he will have equalised and, in all likelihood, gained an isolated but passed pawn on d5. The game still pivots around the central dark squares and, in particular, the d4 square. 12.Nc3 White seeks to prevent an immediate e5 by placing Black's d5 pawn under survaillence. This choice is a popular one although Psakhis prefers

[12.Bc2 when there can follow 12...O-O 13.Be3 Rd8 14.Qd2 Bb4 15.Qd3 Bd6 16.a3 Nf8 and a dynamic position has arisen which is fairly typical of this variation.]

12...O-O 13.Re1? This mistake should have allowed my opponent to gain a meaningful advantage. White can't afford to leave f2 so vulnerable. Instead of this the most frequently chosen alternative is 13.Be3 which continues to maintain the tension. 13...Rd8?! Not so much an error as a missing opporunity. My opponent played this move very quickly. Had I played 13.Be3 then this response would have been correct, (at least according to the opening manuals anyway) so it would appear that Black simply banged out the "book" move without realising I had made an error.

[Why did Black not play 13...Nxd4 when the following line is practically forced 14.Nxd4 Qxf2+ 15.Kh1 Qh4 16.g3 Bxg3 17.Re2 Ne5 18.Rg2 Bf2 19.Nde2 Nxd3 20.Qxd3 Bc5 and Black has three pawns (two of them connected and passed!) for his piece? More than enough for him to claim to be holding the balance in my view.]

14.g3?! This is an odd looking move. As I remember it my idea here was to try to play Nh4-g6. Aside from the fact that this doesn't really threaten anything, Black can easily prevent the plan by moving his rook back to f8 and taking advantage of White's suicidal weakening of the f2 and f3 squares. Simply completing my development with 14.Be3 would have been a far more sensible approach. 14...Nf8 Fortunately for me, my opponent, having played the opening fairly actively and energetically up to this point, suddenly becomes very jumpy and cautious. Perhaps he had been on the end of some defeats in this line were White had taken advantage of the weak g6 and h7 squares. At least this move also enables his light squared bishop to dream about entering the fray. 15.Be3 Bd7 16.h4!? Having thought better of my original plan to occupy g6 I know decided to attempt to bother the Black queen with the manouevre Nf3-h2-g4. On this occasion the plan has some merit as Black has renounced the opportunity to counter attack down the f-file, at least for the moment. 16...Be8 Black is going through contortions in order to rid himself of his "bad" bishop. The idea is to try and engineer its exchange on g6 or h5. 17.Rc1 Continuing with the plan of 17.Nh2 immediately would have been more consistent but I wanted to get my last piece developed and enable my king's bishop to retreat to b1 without blocking the queen's rook. 17...Bh5 18.Be2 Rac8 19.Nh2 19.a3 should also have come into consideration. With this move I demonstrated that I felt my knight was more valuable than my bishop. As the game goes this judgement turned out to be correct but objectively it might have been the wrong judgement. 19...Bxe2 20.Rxe2 White is aiming to double his rooks on the c-file so recapturing with the queen or knight were rejected. 20...Na5 After something of a hiatus over the last 8 or 9 moves the game is beginning to stutter back to life again. Black is aiming to land his knight on c4 which White can easily prevent by playing 21.b3 but this will, in turn, allow Black play 21...Ba3. In this position I felt that I needed to get active fairly quickly as otherwise Black would simply keep improving his position. 21.Ng4 Qg6 22.Ne5 Black can't allow this knight to remain on this outpost and so must exchange off his nice bishop for it. 22...Bxe5 23.dxe5 Nc4 Now Black's knight has found its way to its target outpost. White could drive it off with b3 now but only at the cost of losing his own bishop after 24.b3 Nxe3 25. Rxe3 and Black's passed pawn must give him some sort of advantage. It was for this reason that I decided it was time to try and mix things up a little. 24.Bxa7! Grabbing a hot pawn and setting up a little trap. 24.Bd4 would have been playable too but it's pretty passive. 24...Nd7 Black returns his second knight to the fray and aims to capture the e5 pawn. White could now justifiably play 25.Bd4 but I had seen something else that I liked the look of. 25.Nxd5!? This certainly puts the cat amongst the pigeons! Of course, it isn't totally sound, but it does set Black some challenging practical problems and changes the nature of the game from slow positional manouevring to a tactial fire fight. 25...exd5 26.Qxd5+ Kh8? Wrong square! Black had one chance to refute my combination and this could have been done by playing

[26...Kh7! We'll see in a moment why putting his king here would have made all the difference. 27.Rxc4 Nb6 28.Bxb6 Rxd5 29.Rxc8 The point of 26...Kh7! is that now this move is played without a check! This means that White can't keep his bishop on the board 29...Qxb6 30.e6 and White is lost although Black will have a little work to do rounding up the e-pawn.]

27.Rxc4 The point now is that on 27...Nb6 White plays 28.Rxc8! Nxd5 (or 28...Rxc8 29.Bxb6) 29.Rxd8+ Kh7 30.Rxd5 and Black is done for. The threats to Black's king along the back rank are crucial to these tactics being successful. 27...Qb1+!? Seeing that the above variation leads no where my opponent tries to create confusion. This cunning move is aimed at capturing on a2 when the White bishop will be attacked and the White rook on c4 pinned to the queen. A devious resource that I had overlooked in my analysis. 28.Kh2 It is now important for the White king to choose the correct flight square. On g2 he would have been susceptable to Black capturing on d5 with check. Furthermore the defending pawns are all on black squares so h2 is the safest option. 28...Qxa2 29.Rxc8! White turns the tables on the Black queen. The rook may have been pinned but it turns out to be of now concern. The pinned rook now moves with a tempo to deliver a discovered attack on Black's queen! This compels Black to accept the exchange of his two rooks for the White queen. 29...Qxd5 Black has no other option. 30.Rxd8+ Again, an extra tempo for White's attack due to the Black king's position. Now the passed e-pawn will decide the game. 30...Kh7 31.e6 Qh5 A last desperate attempt at creating problems. White can ignore the threat to the rook. 32.exd7! Qxe2 33.Re8 I think it was only now that my opponent realised he couldn't capture on f2 because the bishop is defending it! There is no way of stopping the d7 pawn from queening now so he resigned. [1-0]

Generated by Aquarium

Points to remember from this game:

1. Sometimes there is no escaping the need to study some opening theory. For several years I had a miserable time playing against the French Defence and eventually realised that I'd have to stop playing 1.e4 or find a line I was happy to research thoroughly. The result of my study was positive both psycologically and in terms of my results.
2. When you have a space advantage in a game the correct strategy is to closely control and restrict your opponent's active possibilities. With 13.Re1? I singularly failed to do that and could have been severly punished. Fortunately my opponent forgot the corollary of this rule which is that when you have a cramped position you should look for ways to activate your pieces and break out even at the cost of a little material. He continued to play a bit passively and eventually I found a way to take advantage.
3. When your king is in check and you are forced to move him be careful to analyse the pros and cons of each available square and don't assume it doesn't make any difference where you place him. In this game Black's choice made the difference between winning and losing.