From raosorio at fibertel.com.ar Sun Feb 1 09:13:02 2009 From: raosorio at fibertel.com.ar (raosorio at fibertel.com.ar) Date: Sun, 01 Feb 2009 11:13:02 -0300 Subject: [Retros] Orbit Informal Retro Tourney 2009 Message-ID: <431f1579262cd.498583be@fibertel.com.ar> Hi firends, The Orbit Informal Retro Tourney 2009 is opened. Every type (orthodox or fairy) of clasic retros and proof games are accepted and very wellcome. The 2009 judge is Thierry Le Gleuher. Kindly send your originals to raosorio at fibertel.com.ar Best, Roberto Osorio From raosorio at fibertel.com.ar Sun Feb 1 10:30:39 2009 From: raosorio at fibertel.com.ar (raosorio at fibertel.com.ar) Date: Sun, 01 Feb 2009 12:30:39 -0300 Subject: [Retros] Problem Paradise 45, january - march 2008 Message-ID: <3bbbfc38209ff.498595ef@fibertel.com.ar> R147 Stephan Dietrich Germany rnbqk1nr/pp1pppBp/8/8/8/8/PbPPP1PP/RN1QKBNR PG 6.0 (14 + 14) C+ R148 Stephan Dietrich Germany r3kbnr/p1pb1ppp/8/8/8/8/Pq2PPPP/2BQKBNR PG 8.0 (11 + 12) C+ R149 Michel Caillaud France Qq2kb2/2p1p1p1/2n1p1pn/p1B5/b1P2R2/4P1P1/B2PP1KP/1N4NR PG 24.5 (14 + 12) C+ R150 Paul Raican Rommania 1n3bnr/pqpkp1pp/4p1R1/1N6/6b1/3P1P1N/P1PK3P/8 PG 25.0 (9 + 13) Maximummer R151 Naoki Matsuzaki Japan A) 2b5/ppppppp1/8/5R2/1P6/8/4PPP1/R3KB2 (8 +8) B) 3Qk3/7P/8/8/P7/8/8/8 (3 + 1) Alice Chess Add 4 pieces so that you can prove wK has moved From naoki.matsuzaki at nifty.com Sun Feb 1 22:15:18 2009 From: naoki.matsuzaki at nifty.com (Naoki Matsuzaki) Date: Mon, 2 Feb 2009 12:15:18 +0900 (JST) Subject: [Retros] Correction: Problem Paradise 45, january - march 2008 Message-ID: <22891597.77721233544518485.naoki.matsuzaki@nifty.com> Dear retro friends, I found mistakes in R151 of the previous post. wQ at d8 is not on B, but on A. wR at f5 is not on A, but on B. The following is correct. R151 Naoki Matsuzaki Japan A) 2bQ4/ppppppp1/8/8/1P6/8/4PPP1/R3KB2 (8 + 8) B) 4k3/7P/8/5R2/P7/8/8/8 (3 + 1) Alice Chess Add 4 pieces so that you can prove wK has moved. The Alice Chess position is printed in one diagram on Problem Paradise; pieces on A are usual and pieces on B are upside-down. So it is easy to confuse R on A with R on B. Regards, Naoki Matsuzaki From andrew at anselan.com Sun Feb 8 19:25:00 2009 From: andrew at anselan.com (andrew buchanan) Date: Sun, 8 Feb 2009 16:25:00 -0800 (PST) Subject: [Retros] How many times could a Diagram be repeated during a proofgame? Message-ID: <176826.51999.qm@web304.biz.mail.mud.yahoo.com> Hi Jonathan, This is a reply to an old mail of yours. I found it in my draft Folder. > As I understand it, we're defining a position as "different" if different > moves are available to each side... (1) We don't get to define what is a position. That is defined for us in the Laws in the section 9.something on Draw by Repetition of Position. > ...even though logically in a game > having the extra option to castle shouldn't prevent one side from > claiming a draw if it wants to. (2) I like your idea that if the current position dominates a previous position, then it should be treated equivalently for Repetition purposes. So for example, if a position occurs 3 times (White to Play) with WKa1, except the first time there was also BQb1 present on the board, then does White have the moral right to claim a draw? After all, he now has all the moves and more that were at his disposal the first time round. But your example (if I've understood your words right) had the domination the wrong way round: White can only lose castling rights not gain them, and its less convincing an argument for a draw if White has less moves available than the first time the diagram occurred. Surely Black could claim that he is making slow but steady progress by whittling away White's castling rights. (Indeed there is a famous problem by somebody where White spends the first 4 double moves eliminating Black's castling rights, returning twice to the original diagram.) Of course if only White has lost castling rights, then Black may be considered to have the right to claim a draw. (Ignoring the mechanical arguments one sometimes gets about whether Black has to write his last move and not actually make it, yawn. By "mechanical", I mean "characteristic of the Laws pertaining to the mechanics of playing the physical game", e.g. touch move, clock management, recording the moves, disqualification for cheating, etc.) > Yet, unless I've missed something, we are defining two positions as > the same even if one is winning but the second is not because of > the 50 moves rule! > > We could argue that a position with 50 moves left is different from > one with 47 moves left is different from one with 2 moves left... (3) The notion of "position" *only* exists in the Laws to define draw by repetition thereof. I suggest that you might use the word "game" instead. Two *games* do map on to the same position even if one game is winning but the second is not because of the 50 moves rule. > Or does this way lie madness? (4) Madness lies all about on this crazy planet where I seem to find myself. But I think here we just have a definitional question. Cheers, Andy --- A J Mestel wrote: > As I understand it, we're defining a position as "different" if different > moves are available to each side, even though logically in a game > having the extra option to castle shouldn't prevent one side from > claiming a draw if it wants to. > > Yet, unless I've missed something, we are defining two positions as > the same even if one is winning but the second is not because of > the 50 moves rule! > > We could argue that a position with 50 moves left is different from > one with 47 moves left is different from one with 2 moves left... > > Or does this way lie madness? > > Jonathan From afretro at yandex.ru Sun Feb 8 23:50:18 2009 From: afretro at yandex.ru (afretro) Date: Mon, 09 Feb 2009 07:50:18 +0300 Subject: [Retros] How many times could a Diagram be repeated during a proofgame? Message-ID: <952571234155018@webmail5.yandex.ru> Dear Andrew, A very fast and selective response to your mail. > So for example, if a position occurs 3 times > (White to Play) with WKa1, except the first time > there was also BQb1 present on the board, then > does White have the moral right to claim a draw? > After all, he now has all the moves and more that > were at his disposal the first time round. With or without BQb1 ? these are different positions. In some fairy types, e.g. Circe, castling rights CAN be restored. Two externally identical positions may appear one after another on the chessboard, differing in that e.g. white has lost the castling right in the first position and has regained it in the second. > Indeed there is a famous problem by somebody where > White spends the first 4 double moves eliminating > Black's castling rights, returning twice to the > original diagram. It was by Nenad Petrovic. > We could argue that a position with 50 moves left is > different from one with 47 moves left is different from > one with 2 moves left... Of course the Dead Reckoning rule can also come into play. Yours, Andrey From G.A.Rol at umcutrecht.nl Mon Feb 9 03:47:35 2009 From: G.A.Rol at umcutrecht.nl (Rol, Guus) Date: Mon, 9 Feb 2009 09:47:35 +0100 Subject: [Retros] How many times could a Diagram be repeated during aproofgame? In-Reply-To: <176826.51999.qm@web304.biz.mail.mud.yahoo.com> References: <176826.51999.qm@web304.biz.mail.mud.yahoo.com> Message-ID: Jonathan is right about "Or does this way lie madness?". The situation is equivalent to the ancient logical "barber-paradox" - the barber who shaves everyone in the village who doesn't shave himself; does he shave himself?". If we do make the assumption that a position 47 moves into a 50M series is "irreversibly" different from one 46 (and 45, 44 ... 1) moves into the series, then clearly these positions are all just the first species in their private 50M series. But if they are all number 1 in their own 50M space and they are all "reversible" into one another then they must all be considered "isomorph" in respect to the 50M convention! Indeed, if the barber shaves himself then he doesn't shave himself and vice versa. The same is (even more) true for the repetition convention. As in every paradox the solution lies in preventing self reference. The postions are part of the "game layer" and the counting of occurrences is part of the "evaluation layer". Entities in the evaluation layer should not be made properties of the game layer and then recycled into the evaluation process. This is an important principle which also affects formal definitions in other areas like AP-logic. Guus Rol. -----Oorspronkelijk bericht----- Van: retros-bounces at janko.at [mailto:retros-bounces at janko.at] Namens andrew buchanan Verzonden: maandag 9 februari 2009 1:25 Aan: The Retrograde Analysis Mailing List CC: Jonathan Mestel Onderwerp: Re: [Retros] How many times could a Diagram be repeated during aproofgame? Hi Jonathan, This is a reply to an old mail of yours. I found it in my draft Folder. > As I understand it, we're defining a position as "different" if > different moves are available to each side... (1) We don't get to define what is a position. That is defined for us in the Laws in the section 9.something on Draw by Repetition of Position. > ...even though logically in a game > having the extra option to castle shouldn't prevent one side from > claiming a draw if it wants to. (2) I like your idea that if the current position dominates a previous position, then it should be treated equivalently for Repetition purposes. So for example, if a position occurs 3 times (White to Play) with WKa1, except the first time there was also BQb1 present on the board, then does White have the moral right to claim a draw? After all, he now has all the moves and more that were at his disposal the first time round. But your example (if I've understood your words right) had the domination the wrong way round: White can only lose castling rights not gain them, and its less convincing an argument for a draw if White has less moves available than the first time the diagram occurred. Surely Black could claim that he is making slow but steady progress by whittling away White's castling rights. (Indeed there is a famous problem by somebody where White spends the first 4 double moves eliminating Black's castling rights, returning twice to the original diagram.) Of course if only White has lost castling rights, then Black may be considered to have the right to claim a draw. (Ignoring the mechanical arguments one sometimes gets about whether Black has to write his last move and not actually make it, yawn. By "mechanical", I mean "characteristic of the Laws pertaining to the mechanics of playing the physical game", e.g. touch move, clock management, recording the moves, disqualification for cheating, etc.) > Yet, unless I've missed something, we are defining two positions as > the same even if one is winning but the second is not because of the > 50 moves rule! > > We could argue that a position with 50 moves left is different from > one with 47 moves left is different from one with 2 moves left... (3) The notion of "position" *only* exists in the Laws to define draw by repetition thereof. I suggest that you might use the word "game" instead. Two *games* do map on to the same position even if one game is winning but the second is not because of the 50 moves rule. > Or does this way lie madness? (4) Madness lies all about on this crazy planet where I seem to find myself. But I think here we just have a definitional question. Cheers, Andy --- A J Mestel wrote: > As I understand it, we're defining a position as "different" if > different moves are available to each side, even though logically in a > game having the extra option to castle shouldn't prevent one side from > claiming a draw if it wants to. > > Yet, unless I've missed something, we are defining two positions as > the same even if one is winning but the second is not because of the > 50 moves rule! > > We could argue that a position with 50 moves left is different from > one with 47 moves left is different from one with 2 moves left... > > Or does this way lie madness? > > Jonathan _______________________________________________ Retros mailing list Retros at janko.at http://www.pairlist.net/mailman/listinfo/retros From andrew at anselan.com Mon Feb 9 19:45:14 2009 From: andrew at anselan.com (andrew buchanan) Date: Mon, 9 Feb 2009 16:45:14 -0800 (PST) Subject: [Retros] How many times could a Diagram be repeated during a proofgame? References: <952571234155018@webmail5.yandex.ru> Message-ID: <609728.3621.qm@web301.biz.mail.mud.yahoo.com> Dear Andrey, > A very fast and selective response to your mail. >> So for example, if a position occurs 3 times >> (White to Play) with WKa1, except the first time >> there was also BQb1 present on the board, then >> does White have the moral right to claim a draw? >> After all, he now has all the moves and more that >> were at his disposal the first time round. > With or without BQb1 ? these are different positions. Yes of course in real life these cannot be claimed to be the same. But I was trying to salvage an interesting conceit from Jonathan's mail, of what I term "moral right" to claim a draw where the positions are not precisely the same. It's possibly not a fruitful idea, but I just thought it was novel. For example: 5k1K/8/5n2/8/8/8/8/N7 After 1.Nb3 N~ 2.Na1 Nf6 3.Nc2 N~ 4.Nd4 Nf6. The position now dominates the initial position and the identical position after 2 moves from each side. Since White's first and third moves were different, he cannot draw with his next move. But I claim that White has the "moral right" to claim a draw now, since his position dominates the earlier two similar positions. >In some fairy types, e.g. Circe, castling rights CAN be restored. Two externally identical positions may appear one after another on the >chessboard, differing in that e.g. white has lost the castling right in the first position and has regained it in the second. This is true and interesting, but I was thinking about orthodox chess to keep this simple. >> Indeed there is a famous problem by somebody where >> White spends the first 4 double moves eliminating >> Black's castling rights, returning twice to the >> original diagram. >It was by Nenad Petrovic. Yup. As I typed those lines, I was remembering a radio program from the weekend where Stephen Fry, a very entertaining British broadcaster, was talking about language and in particular quotations. He was taking the whimsical position that inaccurate or incomplete quotations were more sincere that complete ones, because they came from the heart, while complete quotations can just be looked up. Particularly, I feel, now that search engines make the world omniubiquitous. It was with that curious thought in mind that I decided not to look up the author. >> We could argue that a position with 50 moves left is >> different from one with 47 moves left is different from >> one with 2 moves left... > Of course the Dead Reckoning rule can also come into play. I am not sure that it does. If the draw by 50 is optional, then DR wouldn't get a look in. So let's say that we have the conventions so draw by 50 is mandatory. Fine: but who's to say whether DR is "aware" of the conventions? But it seems to me that there are two possible worlds: (a) DR is aware of the mandatory draw by 50, and factors that into all its thinking. (b) DR is innocent of the mandatory draw by 50. Mandatory draw by 50 will come in like a deus ex machina without any anticipation. Option (a) is probably more interesting, but that doesn't make it more likely to be correct. Cheers, Andrew. From elkies at math.harvard.edu Mon Feb 9 22:49:52 2009 From: elkies at math.harvard.edu (Noam Elkies) Date: Mon, 9 Feb 2009 22:49:52 -0500 (EST) Subject: [Retros] How many times could a Diagram be repeated during a proofgame? Message-ID: <20090210034952.BAD8EF7C5@abel.math.harvard.edu> Note that there is a way for two WTM positions A,B to have the property that for every move from A to some position A' there is a move from B that reaches the same A', and yet A is drawn while B is lost... NDE From G.A.Rol at umcutrecht.nl Tue Feb 10 03:25:15 2009 From: G.A.Rol at umcutrecht.nl (Rol, Guus) Date: Tue, 10 Feb 2009 09:25:15 +0100 Subject: [Retros] How many times could a Diagram be repeated during aproofgame? In-Reply-To: <609728.3621.qm@web301.biz.mail.mud.yahoo.com> References: <952571234155018@webmail5.yandex.ru> <609728.3621.qm@web301.biz.mail.mud.yahoo.com> Message-ID: I just sent 2 problems to "Probleemblad" regarding castling rights in Circe and AP-logic as well. They show amongst others that even "the same castling right" is not always "the same"! These examples are particular to AP-logic; I doubt it makes sense in general to distinguish "an original Circe castling right" from "a restored Circe castling right". Compare it to two knights switching position. The knight identities may be different but their combined impact on the board position is the same. For those interested here one of the Circe-problems: Stipulation: H#2.5 Circe (AP), 2 solutions (use Circe retro-analysis) White: Kb5, Qa2, Pa4,Pb2,Pc4,Pd5 Black: Ke8, R:a8, Pc5. Guus Rol. >In some fairy types, e.g. Circe, castling rights CAN be restored. Two externally identical positions may appear one after another on the >chessboard, differing in that e.g. white has lost the castling right in the first position and has regained it in the second. From per.olin at luukku.com Tue Feb 17 14:05:29 2009 From: per.olin at luukku.com (per olin) Date: Tue, 17 Feb 2009 21:05:29 +0200 (EET) Subject: [Retros] Supercastling Message-ID: <1234897529585.per.olin.64005.IJ5sW3sEq7ViGCi1rgKYFA@luukku.com> Supercastling means castling with a promoted rook. Due to changed FIDE rules it is nowadays illegal. It is said to have been invented by Max Pam, which inspired Tim Krabbe in 1972 (Hesse gives a different year) to compose a threemover including three different white castlings: http://en.wikipedia.org/wiki/Joke_chess _problem#Offbeat_interpretations_of_the_rules_of_chess With the same supermove I composed a twomover (Stella Polaris 1975), Bengt Ingre has published a twomover (Mora Tidning 1993) and we have recently even seen an endgame study with this speciality. Back in the good old seventies I was informed that there is a helpmate fourmover Ke1 pe7 - Ke8 (2+1) with the supercastling: 1.Kf7 e8T 2.Kg6 0000 3.Kh5 Kf4 4.Kh4 Th2#. Could be that as composer was mentioned Dawson, could be that it was somebody else. Could be that this is the first supercastling, could be that I have dreamt the whole problem. Can anybody trace this problem? Best regards Per Olin ................................................................... Luukku Plus paketilla p??set eroon tila- ja turvallisuusongelmista. Hanki Luukku Plus ja helpotat el?m??si. http://www.mtv3.fi/luukku From joost at sanguis.xs4all.nl Tue Feb 17 14:36:22 2009 From: joost at sanguis.xs4all.nl (Joost de Heer) Date: Tue, 17 Feb 2009 20:36:22 +0100 Subject: [Retros] Supercastling In-Reply-To: <1234897529585.per.olin.64005.IJ5sW3sEq7ViGCi1rgKYFA@luukku.com> References: <1234897529585.per.olin.64005.IJ5sW3sEq7ViGCi1rgKYFA@luukku.com> Message-ID: <499B11B6.7070008@sanguis.xs4all.nl> per olin wrote: > Supercastling means castling with a promoted rook. Due to changed FIDE > rules it is nowadays illegal. Tim Krabb? mentions in 'Schaakcuriosa' that he deliberately misquoted the FIDE rules to make this supercastling ('ellenlange rokade' in Dutch) possible. The clauses 'two neighbouring squares' and 'on the same file' were present in the 1971 Dutch translation of the official FIDE rules when he composed this problem in 1972. So if there ever was an error in the FIDE rules, it was changed before Krabb?'s famous composition. The position given in Schaakcuriosa is different from the one given on the wikipedia page by the way: 8/8/4P1p1/3p4/2pP2p1/1pP1k1Pp/1P5P/R3K2R Joost