Die Schwalbe

27 problem(s) found in 6175 milliseconds (displaying 27 problem(s)). [COMMENTDATE>=20200919 AND NOT K='Hilfsrückzüger' AND G='Retro' AND K='Scherzaufgabe'] [download as LaTeX]

1 - P0001141
George Hume
Jamaica Gleaner 12/1891
Weihnachtsturnier 1891
1. Preis
P0001141
(9+9)
Auf welche Gedanken kommen Sie bei dieser Stellung?

Der Ld6 ist keine UWF und der sBg7 wurde auf seinem Ausgangsfeld geschlagen. Nach dem Autor muss der letzte Zug also Lf8-d6 gewesen sein, also illegale Stellung.
Datum der Originalpublikation nicht 100% sicher, laut ACM aus der "Jamaica Gleaner Christmas column".

Originalforderung: How has the position been arrived at and who is the winner, and in how many moves?

From the Jamaica Gleaner: "White mates in two moves. The last move made was by Black playing his Bishop and announcing mate. As it can be demonstrated that the Bishop is not a promoted Pawn and that Black's King's Knight's Pawn was captured on its original square by White's Queen's Knight's Pawn the Black Bishop must have been played from Bishop's square (f8) to Q3 (d6). This being an illegal move, White enforces the penalty of compelling Black to retract it and move his King whereupon White plays 1 PXB(Q) ch (1.gxf8=Q+) and mates next move by 2 Q-B4 (Qf4#). The following is a brief but pointed analysis, demonstrating the false move: White's Pawns have made six captures all on black squares. The Q Kt P (Pb2) made five of these and consequently captured the Kt P on the square upon which it now stands (g7). They could not have captured the Q B which is also lost. The White Bishop is the QRP (Pa2) promoted, the original KB having been captured on its own square as the unmoved Pawns show. To allow this promotion Black's QRP (Pa7) made two captures, the QKtP (Pb7) one, and the QBP (Pc7) two. The KRP (Ph7) has also made a capture, which accounts for the seven pieces White has lost. The Black Bishop is not a promoted Pawn, as if the Black KBP (Pf7) had played to the 7 th square (f2) and then captured a White piece on K or Kt square (e1 or g1) the captures by White Pawns cannot be accounted for without including the Black QB or KRP neither of which is available. As it can be demonstrated, then that the Black Bishop is not a promoted one, and that the KKtP was captured by the White Pawn which now stands on that square, in order to reach Q3 the Black Bishop must have an impossible move.

Der Kolumnist des ACM merkt aber zurecht an:
ACM: The above is a very fine piece of analytical work; but there is a slight flaw in connection with the minor condition, 'mate in two'. In a position of this kind we believe only that which can be proved; thus we do not think that White has any right to enact a penalty, as neither the analysis nor the conditions show that the Black Bishop came from Bishop's square on his last move; indeed, that Bishop may have played outside the Pawns on the very first move of the game which, being played, brought about the position.
HBae: White plays 1 PXB(Q) ch (1.gxf8=Q+). Muß der sK nicht auf f5 stehen? (2019-10-22)
Henrik Juel: Last move (supposedly) was Lf8-d6#, which is obviously impossible and hence illegal
The penalty for this is that Black must replace Ld6 on f8 AND instead make an arbitrary move with his king
So the forward play is
0... Kf5,Kf6,Kh6 1.gxf8=D+ Kg5,Ke5 2.Df4# (2019-10-22)
A.Buchanan: One long-standing approach to resolving illegal diagram jokes is to suppose that only the last move was illegal, with all prior play legal. The illegal move is then retracted, and play continues. Of course, the “illegal move” might in principle be from *any* legal position (even the game array!). So for sanity, we say the illegal move is a simple but somehow illegal shift of a single piece.

So here, candidates for the last move include Pe5-a4+, Sf4-e1+, Ke5-g5+ & B?-d6+. For all of these, White has 6 visible pawn captures, all on dark squares, so Black light-squared bishop is excluded. wPa must have promoted to light-squared bishop, so if the three Black pawns on a-file remain, there is only one unaccounted capture. Thus bPh could not promote, and must be bPg6 now. Thus bPg7 was captured at home, and bBf8 was thus locked in.

So Bf8-d6 is certainly a possible illegal move, but so are e.g. Be8-d6 (as the light-squared bishop is otherwise unexplained) and Pe5-a~. This is an example of an "implausible" joke according to Dawson & Hundsdorfer, because there is more than one retraction to the current position, and one just has to arbitrarily pick the one that makes the forward logic work. (2023-04-02)
A.Buchanan: Another issue is that according to the 1883 laws, White cannot force Black to move their king. The 1883 rules stated:
- If a player touches a piece or Pawn of his own he must move it.
- If he touches one of his adversary's he must take can be taken.
- If he touches plurality of pieces or Pawns of the same colour, in either of these instances his adversary may elect which such piece or Pawn he will call upon him to play or to take, as the case may be.
- If the rules governing the moves of pieces do not admit of the adversary exacting penalty as above, the player must move his King, but may not Castle. If the King cannot be moved without exposure to check, no penalty can then be exacted
So according to this, Black must play Bf8xPg7 as the penalty move.
Was there another revision to the rules between 1883 & 1891? (2023-04-02)
more ...
comment
Keywords: Illegal position, Joke, Retract illegal move (stuck at home), Touch Move, Volet Pawn, Obvious promotion (L)
Genre: Retro
FEN: 6B1/4p1P1/p2b2p1/p5kq/p7/4P1K1/2PPP1PP/3n4
Reprints: American Chess Monthly 1, p. 11, 03/1892
Jamaica Gleaner 30/04/1892
17 Europe Echecs 14 10/1959
Input: Gerd Wilts, 1995-06-03
Last update: A.Buchanan, 2023-04-02 more...
2 - P0001924
Bedrich Formanek
Ass. Slovaque 1966
3. Preis
P0001924
(8+2)
#1 (-:
2 Lösungen
1) 1. gxh8=G# justified by history R: 1. Kg6xGh5 & e.g. Gf5-h5+
2) 1. g8=CM# justified by history R: 1. Kg6xCMh5 & e.g. CMe4-h5+
play all play one stop play next play all
Im orthodoxen Schach hat Schwarz keinen letzten Zug. Schwarz muß deshalb im letzten Zug eine Märchenfigur entschlagen haben. Und sehen P1390927
Henrik Juel: something is wrong here: the claimed mates are not even checks
also, the stipulation should probably be something like
Black and White retract, then #1 (2021-04-30)
A.Buchanan: Yes the problem was the word "dann" which indicates help retractor. The retro is just justification for the forward moves, showing that the relevant fairy piece existed earlier in the game so can be promoted to. What's the name of that principle? (2021-05-01)
Henrik Juel: Thanks for the clarification, Andrew
I think that this principle should remain unnamed and just stay in the joke realm (2021-05-01)
A.Buchanan: Sorry not to be clear: I am talking about the standard fairy principle that if you want to promote to a Princess, there should be one on the problem diagram. Not talking about the joke extension which riffs off this. I thought this was called "Bartel Theme", but it turns out that is something different. (2021-05-01)
Henrik Juel: I see; that principle probably was established soon after the invention of grasshoppers and nightriders
I do not think it has a name, but it is so well established that it should be in the Codex (2021-05-01)
more ...
comment
Keywords: Joke, Last Moves?, Minimal
Pieces: du = Grasshopper (G), lu = Camel (CM)
Genre: Retro, Fairies
FEN: 7b/6P1/7B/6Pk/2P5/3B3K/2P1P3/8
Reprints: (17) diagrammes 97 04-06/1991
MatPlus.net Forum 6/4/2021
Input: Gerd Wilts, 1995-06-03
Last update: A.Buchanan, 2021-06-19 more...
3 - P0002006
Benjamin Glover Laws
Leeds Mercury 12/12/1891
P0002006
(4+7)
#1
Beide Könige stehen im Schach. Schwarz hat zuletzt gezogen, nimmt seinen illegalen Zug zurück und muß stattdessen einen Strafzug mit dem König machen, worauf W mattsetzt.

R: 1. ... d2xSe1=S, dann 1. Kxc3 Dh8#
play all play one stop play next play all
Lösung gemäß 'Retrograde Analysis':
"... both Kings are in check, and we are obviously confronted with something decidedly illegal.
...
In No. 7A Black has just played Pd2xS=S. Replace the move and exact the King move penalty. Then Qh8 mate."
Henrik Juel: Accprding to Retrograde Analysis, 1915, the intended solution does not involve adding pieces as such, rather:
Black retracts the illegal move Pd2xSe1=S+ (exposing Kb2 to a selfcheck from Dh2)
and instead pays the penalty of a king move, Kxc3 (only possibility)
Then White mates by 1.Dh8# (2023-04-13)
Mario Richter: @Andrew: Why did you remove the "illegal position" keyword?
Instead of removing this keyword, I suggest to remove the "Add pieces" KW ... (2023-04-14)
A.Buchanan: Hi Mario, yes good question. I removed "Illegal position" from some genuine "Add pieces" compositions, because it suggests some error in the composition. But on reflection, I think I will put the "Illegal position" back for these, and instead edit the description for the keyword.

Now this problem was in fact incorrectly marked as Add pieces. It's one of Dawson & Hundsdorfer's canonical examples of an "implausible" joke. I.e there is no reason why the intended retraction is the right one, except that it works. These too should be marked as illegal position. Sorry for all confusion (2023-04-14)
comment
Keywords: Joke, Retract illegal move, Illegal position
Genre: Retro
FEN: 6B1/8/8/8/1n3p2/b1N2K2/1k5Q/r1q1n3
Reprints: 7A Retrograde Analysis 1915
Input: Gerd Wilts, 1995-06-03
Last update: A.Buchanan, 2023-04-14 more...
4 - P0004346
Gerhard Paul Latzel
Die Schwalbe 1950
P0004346
(10+3)
#1,5
-sBg5 1. Lxb5,Lxb3 Ta8#
play all play one stop play next play all
-sBg5 (=Vollendung e.p.- Schlag). Nicht Ta1-d1 (=Vollendung w0-0-0), denn Schwarz hätte keinen letzten Zug
Henrik Juel: a slight flaw is that we cannot say whether the entire move was fxg6ep or hxg6ep (2022-07-05)
more ...
comment
Keywords: Castling (wg), Complete an unfinished move, En passant, Joke
Genre: Retro, h#
FEN: 7k/7P/2P1PPPP/1P4p1/b7/1P6/8/R1K5
Reprints: Problem 101-102 09/1966
Input: Gerd Wilts, 1995-06-03
Last update: A.Buchanan, 2022-07-10 more...
5 - P0004870
Hans Apholte
Mannheimer Morgen 1961
P0004870
(5+3)
#0
R: 1. 0-0?
play all play one stop play next play all
See P1388763
James Malcom: Black has no last move, so they must have castled illegally out of checkmate. (2021-04-18)
A.Buchanan: “dann” is used in retractor animation when shifting from retro to forward moves (2021-04-19)
comment
Keywords: Joke, Retract illegal move, Castling
Genre: Retro
FEN: 3R1rk1/5N1n/4KB1P/8/8/8/8/8
Reprints: (XV) Die Schwalbe 8 04/1971
Input: Gerd Wilts, 1995-06-03
Last update: A.Buchanan, 2021-04-19 more...
6 - P0005585
Hieronymus Fischer
56 Fern vom Alltag 1925
P0005585
(5+12)
#0
Einer der sTT muß nach a8 zurückgestellt werden.
play all play one stop play next play all
Lösung aus '64 Schach-Scherze': "Da noch sämtliche schwarze Bauern vorhanden sind, kann keiner der beiden schwarzen Türme durch Umwandlung entstanden sein.
Nun kann aber der schwarze Turm von a8 unmöglich 'herausgekommen' sein. Mithin ist einer der beiden schwarzen Türme nach a8 (oder a7 oder b8) zurückzustellen.
Nach dieser Korrektur ist Schwarz von selbst matt."
in '64 Schach-Scherze' nachgedruckt mit der Forderung "Matt in gar keinem Zug"

vgl. P1309484
Erich Bartel: weiterer Nachdruck (oder Erstquelle?!):
3) 28) 64 Schachscherze 1916 (in dieser Quelle ist kein
Hinweis ob Urdruck oder Nachdruck) (2007-10-30)
Alain Brobecker: Same position and stipulation as P1265678, except the latter one is dated 1910. (2022-11-15)
comment
Keywords: Joke, Illegal position (can't leave home)
Genre: Retro
FEN: 2b5/1pppR1p1/p4p2/3p3p/4r3/4kr1R/2P1N3/4K3
Reprints: 28 64 Schach-Scherze 1915
Das Geheimnis des schwarzen Königs 1960
(III) Die Schwalbe 22 08/1973
Input: Gerd Wilts, 1995-06-05
Last update: A.Buchanan, 2019-10-22 more...
7 - P0006092
Bedrich Formanek
Breyer Gedenkturnier 1973
3. Preis
P0006092
(4+5)
h#1
1. "cxd6"ep b5 2. axb6"ep"#
play all play one stop play next play all
Henrik Juel: Quite cute: the two 'half' white moves add up to one white move
First White removes a black pawn, and after b7-b5 he does not (2021-04-30)
comment
Keywords: Joke, En passant, Complete an unfinished move, Start a move but do not finish it
Genre: h#, Retro
FEN: 8/kpK5/p2P4/P2p4/8/8/8/1r5B
Reprints: (28) diagrammes 97 04-06/1991
Input: Gerd Wilts, 1995-07-17
Last update: A.Buchanan, 2022-02-10 more...
8 - P0008793
Andrej N. Kornilow
Shakhmaty v SSSR 1978
P0008793
(15+8)
#1.5
a) 1. "Ta1-d1+?" ... Td4 2. Txd4# (Completing the illegal castling!)
b) 1. "xc5ep+?" ... Tb5 2. Txb5# (Completing the illegal e.p.!)
c) 1. "xe8=S+?" ... e6 2. Sf6# (Completing the illegal promotion!)

0) 1. Sxe7+! Lxe7 2. f8=B# (Truncating the promotion move!)
play all play one stop play next play all
n in directmate stipulation #n means that White has n moves to do the job. With n=1.5, therefore, one of the White moves is fractional, so we know we are in the realm of jokes, ho ho!

If White's first move is the fractional one, there are three retro tries which attempt to complete: castling, ep & promotion. However all are illegal:
castling: 8 white pawns, so wTa5 came from h1, dislodging wK.
ep: retracting sBc5 to c7 means wLb8 is promoted, but 8 white pawns.
promotion: white made 7 pawn captures, while sBgh were waylaid.

So we consider that White's second move was the fractional one, by omitting the replacement of wBf8 by an officer.
Henrik Juel: Completing the key isn't legal, 1.'Rd1'/'-bPc5'/'e8S'+, but omitting the promotion in the mating move is, 1.Sxe7+ Bxe7 2.'f8'#. Excellent joke. (2003-09-19)
James Malcom: A very witty joke Valladao! (2020-09-24)
A.Buchanan: Really like this joke (2020-09-25)
Henrik Juel: To see the illegality of completing 1.fxe8=S+?, note the captures:
Black captured fxDe, so [Pg7,h7] were captured on their files, while the other six missing black men were captured by white pawns
The illegality of completing 1.0-0-0,bxc6ep? is rather obvious (2020-09-26)
James Malcom: And for those you don't find it obvious: If the White king hasn't moved, then where did wRa5, and wBb8 if bPb5 has just done a double-step, come from? Neither can be promoted pieces, as White still has all eight pawns. Trying to finish castling and en passant therefore both produce illegal positions and thus cannot be the solution. (2020-09-26)
Henrik Juel: Continuing beating the dead horse...
How does the white player actually perform an entire move?
1.0-0-0+: Ke1-c1 and Ta1-d1
1.bxc6ep+: Pb5-c6 and remove sPc5
1.fxe8=S+: remove sYe8 and Pf7-e8 and replace wPe8 with wSe8 (three fractional actions)
2.f8=Y#: Pf7-f8 and replace wPf8 with wYf8
So a marginally better stipulation might be: 'White to move mates in less than 2 moves' (2020-09-26)
A.Buchanan: Hurray I've got the animation working! I agree with Henrik's stipulation. There is a dummy pawn on f8, but not by the Dummy Pawn rule. Instead it's the joke that does it. If Dummy Rule applied, the move would be full length! :) (2022-02-09)
more ...
comment
Keywords: En passant, Start a move but do not finish it, Castling, Promotion (S,B), Valladao Task (half!), Joke (End move, Start move), Dummy Pawn (not! Start move), Complete an unfinished move, waylaid (sBgh)
Genre: Retro, 2#
FEN: 1B1N1bB1/p2ppP2/2P5/R1pk1N2/1r2p3/1P2P1P1/4PP1P/R1K5
Reprints: (III) Quartz 4 1997
Input: Gerd Wilts, 1997-06-21
Last update: A.Buchanan, 2023-04-08 more...
9 - P1066829
Imants Dulbergs
The Ural's Problemist 04-06/2004
2. Thematurnier
Spezielle ehrende Erwähnung
P1066829
(8+6)
s#4.75
a) 1. dxe6ep Tb2 2. Sxe8 g5 3. Sd6 g4 4. Se4 g3 5. Sf2 gxf2#
play all play one stop play next play all
Beide Könige im Schach - wie entstand die Stellung? Zulaetzt geschah 0. Td4-d1+ Be7-e5
Mario Richter: Shouldn't this rather be a "s#4.75"? (2010-08-13)
Mario Richter: What was the theme of that tourney? (2010-08-13)
A.Buchanan: I think the theme was retro selfmates (2021-02-15)
A.Buchanan: What does wLg8 do? (2021-02-15)
comment
Keywords: En passant, Complete an unfinished move, Joke
Genre: Retro, s#
FEN: 1r2r1BB/2N5/6p1/3P4/8/8/p5P1/kn1RKN2
Input: Frank Müller, 2004-11-01
Last update: A.Buchanan, 2021-02-15 more...
10 - P1108458
Werner Keym
Main-Post 1968
P1108458
(14+0)
Ergänze den sK, dann #1
a) +sKd3 1. 0-0-0? Castling rights lost
b) +sKf7 1. g8=D#
play all play one stop play next play all
+sKd3? und 1.0-0-0# macht nicht, veil die Stellung ist illegal (saB & sbB).
Das Brett wird um 180° gedreht, dann +sKf7 und 1. g7-g8=D#
Henrik Juel: I believe that the try is
add sK on d3 and 1.0-0-0#
This addition is illegal, however:
the white h-pawns captured all 15 missing black men, but [Pa7,b7] need three captures to promote, and only two white men are missing (2023-04-13)
comment
Keywords: Joke, Board Rotation (180), Add pieces (sK), Cant Castler
Genre: Retro
FEN: 6B1/4R2P/P6P/B6P/7P/7P/1P5P/R3K1N1
Input: Gerd Wilts, 2010-06-23
Last update: A.Buchanan, 2023-04-15 more...
11 - P1184603
Frank Melville Teed
891 Dubuque Chess Journal 05/1874
P1184603
(5+5)
s# in wieviel Zügen?
In einen eineinhalb Zügen.
Weiß komplettiert die Rochade mit Kc1, dann Da1,Db1,Tb1#
play all play one stop play next play all
Henrik Juel: Of course, the correct way of castling is K to c1 and then T to d1 (2022-03-03)
comment
Keywords: Joke, Complete an unfinished move
Genre: s#, Retro
FEN: 8/8/8/8/p7/kp2Q3/qrPB4/3RK3
Reprints: CS9 Maryland Chess Review 08/1874
Input: Frank Müller, 2011-01-10
Last update: A.Buchanan, 2022-03-03 more...
12 - P1260207
Charles Henry Wheeler
892 Dubuque Chess Journal 05/1874
P1260207
(4+7)
s# in wieviel Zügen?
1) R: 1. ... 0-0-0, dann 1. Txg6#
2) R: 1. ... 0-0-0, dann 1. Df7#
play all play one stop play next play all
Weiß kann Selbstmatt ohne einen eigenen Zug erzwingen.
Schwarz rochierte im letzten Zug, obwohl er im Schachstand und ignorierte dabei auch das Schach auf d8. Beides ist illegal. Er muss diesen Zug zurücknehmen und statt dessen Df7# oder Txg6# spielen.
A.Buchanan: No retro analysis to show that last move was in fact castling. Position is not illegal. (2019-10-21)
James Malcom: Perhaps that's why it labeled as a joke then. Andrew. (2020-10-20)
A.Buchanan: Yes it’s a joke but there is an existing species of problem where the position Is illegal. This is kind of like Conan Doyle vs Agatha Christie: here we are only told the key clue after the fact. I am sadly interested in classifying the main families of jokes, identifying which ones are fairies as well etc. This one is not fairy I think. In constraint promotion into foreign units can be joke depending on stipulation, but is definitely fairy (2020-10-21)
comment
Keywords: Joke, Retract illegal move (castling)
Genre: s#, Retro
FEN: 2kr1b2/p3p3/4K1Br/B3R3/8/5q2/8/8
Input: Frank Müller, 2013-01-19
Last update: Alfred Pfeiffer, 2019-10-22 more...
13 - P1322154
Antoine Huberty
AJEC (Belgischer Fernschachbund) 01/10/1935
P1322154
(13+12)
#1 (Wer?)
1. Dc4#
play all play one stop play next play all
Mit Weiß von unten nach oben spielend wäre die Stellung illegal, also spielt Weiß von oben nach unten (Drehung um 180°) und kann mit 1. Dc4 (oder präziser 1. Df5 beim richtig orientierten Brett) mattsetzen.
eingebettet in eine Geschichte "Un peu de fantaisie - qui fait mat en un coup"
Henrik Juel: The reason for illegality is too many white pawn captures
axb, bxcxd, hxg need four missing black men, which is indeed the case, but [Lc8] was captured at home by an officer (2016-07-10)
A.Buchanan: 1.Sg3#? is the thematic try (2023-04-03)
comment
Keywords: Joke, Illegal position, Whose move?, Board Rotation
Genre: Retro
FEN: 1rn5/NpQp2b1/1P2p1P1/p2P1p2/1k2P2p/5P2/R1PP2P1/1N1K1n1r
Input: Mario Richter, 2016-07-10
Last update: A.Buchanan, 2023-04-03 more...
14 - P1340386
Georges Emile Barbier
Recreationist 06/1873
P1340386
(6+8)
#2
1) R: 1. ... 0-0, dann 1. Kxd8 Lf6+ 2. Ke8 De4#,bxc8=D/T
1. ... bxc8=D/T+ 2. Kxc8 Da8#
2) R: 1. ... 0-0, dann 1. Tg8,Tf8 De4+ 2. Kxd8 De7#
play all play one stop play next play all
Heft 7 (08/1873) S.91: The position being one occuring in actual play with White to move, the question is 'What was Black's last move?'. Clearly not a pawn or bishop. Neither could it have been the Kt, for it must have moved from B4 or Kt5, and from either square it would have checked the White K, which must consequently have moved, and therefore could not occupy K 3, as given on the diagram. Nor could the Rook have moved from K square for a similiar reason, the check requiring one of the white pieces to cover it, or the King to move. Then the Black King must have moved - but from where? Not from B or R squares, which are guarded by two pieces. It must have moved therefore from K square, which necessitates the placing of the Rook on its square. Black therefore Castled on his last move, which by the Chess law was an illegal move, and he must pay the penalty by replacing the King and Rook on their original squares, and move one of the pieces touched.
Originalforderung: How is it possible for White to effect mate in two moves by strict chess?

'Recreationist': "A CHESS PUZZLE. We give below an interesting position which is to be looked upon as an end game occuring in actual play. It is calculated to test the ingenuity of those of our subscribers who delight in unravelling mysteries."

Erinnert von der Machart her an P1323153 und ähnlich gelagerte Probleme.

Interessanter Leserbrief von F. Dunne Okt. 1873 S.121: "It appears to me (albeit I amone of the solvers), that Mr. Barber's 'logical' solution of his Chess Puzzle is 'il'-logical, and I believe the following will clearly prove it so. Mr. Barbier says, 'What was Black's last move? Clearly not a pawn or bishop'; and he proceeds to prove that Black 'must' have made a false move with his King, 'because' he could not legally have moved it or any other piece into the position it or they now occupy.
Now surely that is not 'logically' proving that he 'must' have moved his King! For by the same 'logic' I can prove that he must have made a false move with, say, the Knight or any other piece.
'What was Black's last move? Clearly not the King, for all the squares from he could have reached the one he now occupies, are already occupied, either by his own, or by his opponet's pieces, or under the range of the latter's pieces; and he could not have Castled, as the square over which he would have to pass is commanded by one of the adverse pieces.
It is quite evident the pawns have not been moved, and, therefore also, not the bishop. The Rook cannot have been move last, or the White King would not occupy the square he now does. The he 'must' have moved the Kt, and as he could not legally have moved this piece to the square it now occupies, he must have made a false move with it.
Now, one conclusion is as logically arrived at as the other, and by parity of reasoning any other of Black's pieces can be proved to be te one last moved, as Castling across check is no more strict Chess, than wrongly moving a piece."

Gedanken dieser Art haben vermutlich Roberto Osorio & Co. zur Einführung des Begriffs MDR (Minimum Deviation from the Rules) inspiriert (s. Hinweis P0005584)

Antwort vom Autor im 'Recreationist 12/1873 S.154: "In reply to Mr. Dunne's letter in No.9 I beg to say that the solution of the Puzzle cannot be taken apart from the conditions attached to it. Any solution means the solution of something or other, and must be taken inconnection with that something.
The question is to find a way in which White mates in two moves. I agree that if, saying nothing about a mate in two moves as a condition, I endeavoured merely to prove Black's last move, Mr. Dunne's argument would be perfectly sound. But the fact of Black's castling is not an absolute fact; it is only relative. He castled because thereby I can mate him in two moves which Mr. Dunne's move does not do, and which is the very thing that is required to be done.
Henrik Juel: So even if one accepts the dubious retro reasoning intended, the problem is cooked by 0... Kxd8 1.bxc8=DT,Lf6+ (2017-09-30)
A.Buchanan: Dubious or not, retract-and-replay *is* one of the canonical chess problem jokes that our great-great-grandparents must have split their sides laughing over. I am pretty sure there is a typo in the diagram. sLc8 should be b8. This restores soundness and adds a retro try. wBb7 is still necessary to cover c8. (2017-09-30)
A.Buchanan: Have pushed sLc8 to b8, to remove the obvious typo. (2018-10-06)
A.Buchanan: I would classify these problems as jokes, not because the positions are illegal, but because imprecise reasoning is required to determine the illegal move. This is a particularly nice example though. Any thoughts? (2018-10-06)
SP: Your "obvious typo" is imaginary; the intended solution after Kd8: is
explicitly stated to be 1.bc8:=Q+ Kc8: 2.Qa8# (p. 91, viii/1873), quite
impossible with a bBb8. Please correct the position. (2023-02-18)
A.Buchanan: Hi SP. thanks for your research. Have you got a link to this material - that would be very helpful for checking similar situations. Otherwise our discussions here are often speculative. Bad news for the composer though: what I had thought was a typo turns out to be a cook. It would be good to know the version of the touch move rules applying in 1873, as the rook penalty move is clearly thematic. (2023-04-03)
A.Buchanan: The stuff about bS having just made an illegal move is basically Dawson & Hundsdorfer's distinction between plausibility & implausibility. This is an implausible composition, and having said that, one need agonize no longer, and just enjoy it for the best it can be at this silly idea (2023-04-03)
comment
Keywords: Illegal position, Joke, Retract illegal move (castling), Touch Move, Castling
Genre: Retro, 2#
FEN: 2bN1rk1/1Ppp1pBp/6Nn/8/8/4K3/8/7Q
Reprints: 617 Dubuque Chess Journal 08/1873
Input: Mario Richter, 2017-09-30
Last update: A.Buchanan, 2023-04-03 more...
15 - P1346371
Tomislav Petrovic
H3 Problemkiste (159-160) 07/2005
P1346371
(9+4)
h#0,5
3 Lösungen
1) 0,5 ... -sBb5# (Teil von axb6ep)
2) 0,5 ... -sBf5# (Teil von gxf6ep)
3) 0,5 ... Tad1# (2. Teil von 0-0-0)
play all play one stop play next play all
A.Buchanan: This is definitely not h#0.5 rather it's h#0.25 or #0.5.
This is retro joke not fairy, imho (2022-03-03)
comment
Keywords: Half-moves, Castling, En passant, Complete an unfinished move, Joke
Genre: Retro
FEN: 8/7Q/BP3P2/1p2Rp2/3p4/1P1k4/1P6/R1K5
Input: Erich Bartel, 2018-01-31
Last update: A.Buchanan, 2022-03-03 more...
16 - P1370911
James Malcom
Andrew Buchanan

(4) MatPlus.net Forum Retro/Math 21/12/2019
P1370911
(12+14)
PG in 12.5
(-:
1. e4 d5 2. e5 Dd6 3. exd6 Kd7 4. dxe7 Kc6 5. Lb5+ Kxb5 6. c4+ Kxc4 7. e8=T Kd3 8. Df3+ Kc2 9. d3 Lh3 10. Ld2 Lxg2 11. Lb4 Lxh1 12. Sc3 Lg2 13. 0-0-0-0-0-0#
play all play one stop play next play all
http://matplus.net/start.php?px=1609818957&app=forum&act=posts&fid=xshowr&tid=2402&pid=20379#n20379
Objective: Staugaard (Pam-Krabbé) castling as mating move.
more ...
comment
Keywords: Unique Proof Game, Staugaard castling, Joke, Prenix, Promotion (T), Castling as mating move, Superseded by (P1385595)
Genre: Retro, Fairies
Computer test: C+ Natch 3.1 has no solutions in 12.5 moves & 1 solution for first 12.0 moves. (H.Juel)
FEN: rn3bnr/ppp2ppp/8/3p4/1B6/2NPKQ2/PPk1RPbP/R5N1
Input: A.Buchanan, 2019-12-23
Last update: James Malcom, 2022-02-26 more...
17 - P1375286
Andrew Buchanan
James Malcom

PDB Website 30/4/2020
P1375286
(6+3)
#2
(-:
1. dxc7ep! b4 2. c8=D,T#

R: 1. ... c8-c6?! and earlier c8=sB?!
play all play one stop play next play all
Supersession of P1380851

Superseded by P1380851

The 2018 FIDE laws state: "3.7.2 on its first move the pawn may move as in 3.7.1 or alternatively it may advance two squares along the same file, provided that both squares are unoccupied."

Hence Black's newborn 8th rank pawn, which has never been moved before, reserves the right to commence a double-step on its first move, and likewise White receives the right to capture it en passant as they do with a 7th rank pawn.
Henrik Juel: This un-dummy-pawn is like a pawn created on c8 by the Einstein condition
The retroplay looks wrong, what about 1... d8-d6!? 2.d7-d8=sB!? c6xYb5 (2020-04-30)
James Malcom: That makes much more sense Henrik. I have edited it accordingly. (2020-04-30)
A.Buchanan: You don't like Adrian's (: haha? What about :) then? In heraldic terms, it would be described as "regardant". See 270 on https://www.heraldica.org/cgi-bin/atlas.pl?12. I don't know the word for "non-regardant", which is the default direction for the head, e.g. most of the others on that page.
We could replace wBa6a7 with wSa6, but alas having the 3rd knight is non-thematic & distracting. The other thing I would've liked to do is empty b2 so the promotion is forced to be to D. Such a tiny problem should have precision promotion. Needs more thinking. (2020-05-01)
James Malcom: UPDATE: The position has been edited to have one less piece and a precise queen promotion. (2020-10-12)
A.Buchanan: There is dialogue here which is now orphaned by a change of diagram with new matrix. Suggest we revert to the older diagram and mark it superseded by a new PDB entry here (2020-10-12)
James Malcom: I agree-it is now done. (2020-10-12)
more ...
comment
Keywords: En passant as key, Joke, Joke promotion (b), Tolerated dual promotion (D/T), Promotion (D/T), Superseded by (P1380851)
Genre: 2#, Retro
FEN: k7/PN1N4/PKpP4/1p6/8/8/8/8
Input: James Malcom, 2020-04-30
Last update: A.Buchanan, 2022-09-18 more...
18 - P1375777
James Malcom
PDB Website 10/4/2020
nach Josef Cumpe
P1375777
(1+8)
Last two moves?
(-:
R: 1. 0-0-0# a7-a8=sT
play all play one stop play next play all
See P1234039
Henrik Juel: Missing Joke keyword, I guess (2020-05-11)
A.Buchanan: Curious that retro a7-a8=sT discomforts the animation still - maybe you should report to Gerd? (I trouble him with enough stuff already - don't want to be the only one emailing him! :-) (2020-05-11)
A.Buchanan: Maybe +sBe7f7 to refute R. ... e8=sK/fxe8=sK :-) Note this "cook" is actually prevented in the original. (2020-05-11)
A.Buchanan: Oops and a more major cook R: 1. Se8/g8-f6+ (2020-05-11)
James Malcom: This problem was only half-finished before I fell asleep. It’s fixed now. (2020-05-11)
A.Buchanan: Great! You could save another piece I think -sLg6, -sBf7, + sDf7. This also removes the obtrusive promotion (2020-05-11)
James Malcom: Yes, that is true. Position edited. (2020-05-11)
James Malcom: I see nothing wrong with fiddling if it improves economy. (2020-05-11)
A.Buchanan: If promotion to Bl unit is allowed, can’t Bl just have played e8xd7+ or g8xh7+? Can replace bPd7 with bR but eliminating bPh7 is more complicated. Need +wPh7 +bPg6h6. And also bRb7 to prevent discovered check by bPc8 prior to e7-e8=bK. I think that’s watertight now! :-) (2020-10-13)
A.Buchanan: The issue is that there are two or three levels of Bl promotion joke: this problem relies on the "basic" joke where black officers can be created. But where's the line to stop us promoting to Bl pawn or king? If we go that far, then a position like this 2kr3K/1r1r1qrR/7p/8/8/8/8/8 is required. Oh dear: sorry to have brought it up :( (2020-10-13)
more ...
comment
Keywords: Castling in the retro play, Promotion in the retro play (t), Rex solus (w), Joke, Joke promotion, Type C
Genre: Retro
FEN: 2kr3K/1p1ppqrp/8/8/8/8/8/8
Input: James Malcom, 2020-05-11
Last update: Alfred Pfeiffer, 2020-10-14 more...
19 - P1380852
James Malcom
Andrew Buchanan

MatPlus.net Forum 12/10/2020
after Josef Cumpe
P1380852
(1+7)
Last two moves?
(-:
R: 1. 0-0-0+ a7-a8=sT
play all play one stop play next play all
See P1234039 and P1375777
The joke here is that pawns may promote to enemy officers (but not to pawns or kings)
Henrik Juel: R: 1... 0-0-0+ 2.a7-a8=sT! (2020-10-12)
A.Buchanan: Maybe this is a moderate joke where we allow promotion to Bl officers, while son-of-P1375777 can be the extreme joke where promotion to any Bl unit is allowed (i.e. pawn & king too), including in the history of the game. What would Josef Cumpe think? :-) He and I are both dressed as clerics in out chesscomposers' blogspot pics: http://chesscomposers.blogspot.com/2012/08/august-16th.html. Perhaps he was a real one though? (2020-10-13)
comment
Keywords: Last Moves?, Joke promotion (t), Rex solus, Type C, Castling in the retro play, Joke, Promotion in the retro play (t), Castling (sg)
Genre: Retro
FEN: 2kr2K1/1p1p1npr/8/8/8/8/8/8
Input: A.Buchanan, 2020-10-12
Last update: A.Buchanan, 2023-08-15 more...
20 - P1380882
James Malcom
Andrew Buchanan

PDB Website 14/10/2020
after Josef Cumpe
P1380882
(2+7)
Last two moves?
(-:
R: 1. ... 0-0-0+ 2. a7-a8=sT
play all play one stop play next play all
See P1234039, P1375777 and P1380852.
The joke here is that pawns may promote to *any* unit (friend or enemy; officer, king or pawns).
Henrik Juel: R: 1... 0-0-0+ 2.a7-a8=sT
not 2.e7-e8=sK, because then sTa8 would have moved, and castling not allowed (2020-10-14)
A.Buchanan: Exactly, Henrik. Also: sB on 7th rank could retract to 8th rank, so we need sT instead (2020-10-14)
more ...
comment
Keywords: Last Moves? (2), Type C, Castling in the retro play, Non-standard material (tt), Joke, Joke promotion (t), Promotion in the retro play (t), Minimal, Castling (sg)
Genre: Retro
FEN: 2kr3K/1r1r1qrR/7p/8/8/8/8/8
Input: A.Buchanan, 2020-10-14
Last update: A.Buchanan, 2023-08-15 more...
21 - P1380896
Andrew Buchanan
MatPlus.net Forum 12/10/2020
P1380896
(13+13) C+
PG in 6.5
(-:
1. b4 g5 2. b5 g4 3. b6 g3 4. bxa7 gxh2 5. axb8=sS! hxg1=wT! 6. Txh7 Txh7 7. Th1
play all play one stop play next play all
The joke here is that pawns may promote to foreign units.
Henrik Juel: The testers probably do not work here, but this seems unique
1.b4 g5 .. 4.bxa7 gxh2 5.axb8=sS hxg1=wT 6.Txh7 Txh7 7.Th1 (2020-10-14)
A.Buchanan: According to Joost De Heer, WinChloe has a category “promotions adverses”, and under this, the problem is C+. Looking now for a full Homebase without utilising promotion to enemy pawn, which makes it too easy (2020-10-15)
comment
Keywords: Unique Proof Game, Joke, Joke promotion (sT), Homebase (w), Phoenix (s), Prenix (T), Impostor (sT)
Genre: Retro, Fairies
Computer test: C+ WinChloe
FEN: rnbqkbn1/1ppppp1r/8/8/8/8/P1PPPPP1/RNBQKB1R
Input: A.Buchanan, 2020-10-14
Last update: A.Buchanan, 2022-09-18 more...
22 - P1385169
Werner Keym
Hannoversche Allgemeine Zeitung 2003
P1385169
(5+2)
#1
b) wSe1->d2
a) 1. Sc2#
b) 1. Ta4#?
Schwarz zog zuletzt nicht und ist am Zug, aber laut Forderung soll Weiß am Zug sein. Das funktioniert nur, wenn Weiß seinen begonnenen Zug vollendet:
1. Ta1-d1! (Halber Zug als zweiter Teil von 0-0-0) Db2#
play all play one stop play next play all

Duplicate Diagram: P0004961

Der Teil b) des Problems erschien allein im Weser-Kurier 1968 (P0004961), der Zwilling in der HAZ 2003.
more ...
comment
Keywords: Minimal, Miniature, Complete an unfinished move, Whose move?, Joke
Genre: Retro, n#
FEN: 8/8/8/8/1R6/kP6/q7/R1K1N3
Input: Alfred Pfeiffer, 2021-01-08
Last update: A.Buchanan, 2022-03-03 more...
23 - P1389077
Adrian Storisteanu
Discord Chess Problems & Studies Server 4/4/2021
2. Platz
CP&S Discord Server Composition Tourney 0 {}
P1389077
(3+2)
Switcheroo # =<1* (-:
(i.e. swap two pieces for mate in one or less)
1. De4# but faster is:
Swap Tc4<->Ba1 and now 1. Ta1->d1, completing 0-0-0#
play all play one stop play next play all
PR Edderiofer wrote: "Another mid-castling position. "=1" here initially suggested to me "in 0 or 1 plies", but of course, 0.5 = 1 too. (Should that be 0.25 if it's in a helpmate? I don't know.)"
Henrik Juel: based on the keywords, probably
switch La1 and Tc4, then 1.Td1#, i.e. complete the castling (2021-04-30)
comment
Keywords: Joke, Aristocrat, Minimal, Miniature, Castling (Complete or retract)
Genre: Retro
FEN: 8/8/8/4Q3/2R5/3k4/8/b1K5
Reprints: MatPlus.net Forum 4/4/2021
Input: A.Buchanan, 2021-04-29
Last update: Alfred Pfeiffer, 2021-07-27 more...
24 - P1389103
LilHamood
Discord Chess Problems & Studies Server 4/4/2021
12. Platz
CP&S Discord Server Composition Tourney 0 {}
P1389103
(3+2)
Make a legal move (-:
Henrik Juel: maybe 1.e8=K (2021-04-30)
comment
Keywords: Joke, Minimal, Miniature, Illegal position (no wK), Promotion (wK)
Genre: Retro, Fairies
FEN: 8/4P3/8/5N2/8/8/2Q3b1/7k
Reprints: MatPlus.net Forum 4/4/2021
Input: A.Buchanan, 2021-04-30
Last update: A.Buchanan, 2023-12-11 more...
25 - P1390927
Andrew Buchanan
v MatPlus.net Forum 26/06/2021
after Bedrich Formanek
P1390927
(11+2)
#1 (-:
9 solutions
PPRA (Partial PRA = PRA except ignore cases having no solution)
1) 1. g8=CM# R: 1. Kg6xCMh5 CMe4-h5+
2) 1. g8=AD# R: 1. Kg6xADh5 ADc2(d3,e4)-h5+++
3) 1. c8=GZ# R: 1. Kg6xGZh5 GZc2-h5+
4) 1. c8=GQ# R: 1. Kg6xGQh5 GQc2-h5+
5) 1. b8=GF# R: 1. Kg6xGFh5 GFd3-h5+
6) 1. bxa8=GE# R: 1. Kg6xGEh5 GEe4-h5+
7) 1. b8=N# R: 1. Kg6xNh5 Nd3-h5+
8) 1. g8=QN# R: 1. Kg6xQNh5 QNe4-f6-h5+
9) 1. h8=TP# R: 1. Kg6xTPh5 TPf5-h5+
Minor duals, with both mates separately provided elsewhere:
1) 1. g8=GR,b8=GR# R: 1. Kg6xGRh5 GRd3(e4)-h5+
2) 1. g8=MG,h8=MG# R: 1. Kg6xMGh5 MGc2(d3,e4)-h5+
play all play one stop play next play all
What was Black's last move? It can only have been Kg6-h5, fleeing check. But what was White's prior move: it could only have been a fairy piece moving to h5 from the diagonal c2-f5, discovering check. Then this piece was captured by bK. What kind of piece was it? The idea is that for each feasible piece, there should be exactly one corresponding promotion mate.

1) Camel = (1,3)-Leaper
2) Eagle
3) Gazelle = (3-5)-Leaper
4) Giraffe Quintessence = right-angle turn Girafferider, Giraffe = (1,4)-Leaper
5) Greater Leafhopper
6) Greater Treehopper
7) Nightrider
8) Quintessence = right-angle turn Nightrider
9) Rookhopper

Minor duals, where both solutions are separately provided elsewhere:
1) Gnurider
2) Marguerite = Eagle+Grasshopper+Hamster+Moose+Sparrow, only the first two sub-creatures are used)

Tries:
1)It looks as if one might rotate the board 180 degrees: 1. Bb3#! Not 1. b3+? Kxa3!
The position is legal because e.g. R: 1. g8=B+.
However this doesn't work because it's not thematic :)
2) It looks as if R: 1. Kg6-h5 c2-c3+ might be good. Who's to say in a fairy form that wL can't begin on b1? Well if you can show me a fairy piece which can throw other pieces around the board, then let's consider it, but fairy conditions are excluded here, for sanity's sake.

Would be cooks - but the soundness is protected by the halo of PPRA :)
Bishop Eagle, Boy Scout, Dabbaba, Equihopper, Lancer, Moarider Lion, Radial Leaper
AB: See P0001924. Bedrich Formanek is happy with his problem, but welcomes a larger zoo.

I think this is a kind of PRA problem (although PRA is defined currently only for castling and ep). A PRA problem is regarded has having one solution with many parts. So maybe that points the way how to stipulate the problem. The joke version PRA (= Partial PRA) says that PRA applies to all the parts that it does, but not to the others, particularly those with no solution).

It's clear that there are more pieces which would solve the problem. Why not Gnurider or Gazellerider instead of Gnu or Gazelle? Why not Gnurider instead of Nightrider? Etc. Why not Grasshopper instead of Rookhopper? The PRA notion would prevent these from cooking the problem: each is indeed a separate part. As long as whatever was just captured can be uniquely reborn to deliver mate, the problem is sound. The published solution shows the most basic representative piece for each of the patterns, with no unused capability.

As a PRA problem, if a kind of fairy piece might legitimately have been captured on h5, yet does not offer a mating promotion, that would make the problem unsound. And indeed there are two such creatures known: Dabbaba and Lancer. However fortunately we are working with the looser PPRA meta-convention which only applies where it applies.

In earlier versions, the eagle was considered a try, but actually I think it implied an insoluble PRA part, but fortunately could be fixed.
Henrik Juel: if last move was Kg6xGh5, 1.gxh8=G#
if last move was Kg6xYh5 (Y=1,3-S=Camel), 1.g8=Y#
if last move was Kg6xYh5 (Y=rookhopper), 1.gxh8=Y# (This looks like a cook)
if last move was Kg6xYh5 (Y=5,3-S), 1.c8=Y#
if last move was Kg6xNh5, 1.b8=N# (2021-06-20)
A.Buchanan: Thanks Henrik - as discussed: I don’t think Rookhopper is a cook, but is a separate part of the PRA solution. Maybe it’s the fundamental solution and Grasshopper is the one with unneeded additional functionality but Grasshopper is the more common one. Nice for some of these unfamiliar creatures to get some exposure... (2021-06-20)
comment
Keywords: Joke (PPRA), Phoenix (9), Last Moves?, Partial Retro Analysis (PRA), Rex solus, Promotion (9), Minimal
Pieces: tu = Rookhopper (TP), sr = Camel (CM), su = Nightrider (N), lu = Gazelle (GZ), dl = Eagle (AD), sl = Quintessence (QN), lr = Giraffe Quintessence (QG), du = Greater Treehopper (GE), dr = Greater Leafhopper (GF)
Genre: Retro, Fairies
FEN: b7/1PP3PP/7B/6Pk/8/2P3K1/P3P3/1B6
Input: A.Buchanan, 2021-06-19
Last update: A.Buchanan, 2022-01-09 more...
26 - P1402593
Andrew Buchanan
PDB Website 09/07/2022
after G.P.Latzel
P1402593
(10+4)
h#1.75 (-:
hint rot13: pbqrk negvpyr svsgrra
0. ... [-bPg5] 1. Lxb3 Ta8#
play all play one stop play next play all
Clearly an unfinished move joke. By a usual convention for these things, a player might be halfway through a castling, an en passant, or a promotion. 1.75 is nearly 2.0, so Black would be the moving player.

Black is not in the middle of an e.p. or castling, so the only possibility is a promotion. Black has lifted up the pawn, to replace it with an officer on the 8th rank. However, White has apparently made 12 pawn captures, accounting for all missing Black units, so Black is not part way through promoting a pawn.

Therefore it's not Black in the middle of a move. By a joke application of Article 15, we say that it's *White* in the middle of a move instead. So 1.75 - 0.5 = 1.25 and it's h#1.25.

- White can't be part way through a promotion, because all White pawns are on the board.
- If White were in the middle of castling, then the pawn capture balance would be ok, but Black would have no prior move.
- If White were in the middle of en passant h5xg6, then bPg5 can help with capture balance, but still there is one capture short for the balance.
- So White is in the middle of en passant f5xg6. If we complete the joke move by removing bPg5, then the position is legal, with 12 White pawn captures and 13 missing Black units. A sound h#1 awaits.
After P0004346
Henrik Juel: Not completion of 0-0-0, because Black has no last move
Completion of f5xg6ep is feasible, and then 1.Lxb3 Ta8#
Stipulation should be h#1.25, I think (2022-07-10)
A.Buchanan: Hi Henrik: it’s intended to be h#1.75 :-) Can black complete any Valladao move? And if not then what do we do? :-) (2022-07-10)
Henrik Juel: Thanks Andrew
So Black must complete a move, but his four men are stuck, and white pawns captured the remaining 12 black men; so there is nothing for Black to complete
Looks like a weird joke... (2022-07-10)
A.Buchanan: Sorry you don't like the Valladao joke Henrik. "1.75 minus 0.5 = 1.25" is a novel way to combine "unfinished move" with Article 15. I also like the fact that all the cases of pawn capture counting are exact, with no "retro dressing" unit purely to contribute to a balance.s (2022-07-10)
comment
Keywords: Joke, Complete an unfinished move, En passant, Castling (wg Not!), Promotion (Not!), No legal last move for Black
Genre: h#, Retro
FEN: 7k/5p1P/5PPP/1P4p1/b7/1P6/6PP/R1K5
Input: A.Buchanan, 2022-07-10
Last update: A.Buchanan, 2023-12-08 more...
27 - P1407481
ChatGPT
Andrew Buchanan

Discord Chess Problems & Studies Server 29/01/2023
P1407481
(2+2)
#2
1. bxa3+ Kd4 2. Kb2#
play all play one stop play next play all
Chess problem by AI program ChatGPT

Q: Can you give an example of a chess retrograde analysis problem?

A: A retrograde analysis problem in chess is a problem where the goal is to determine the sequence of moves that led to a given position. For example:

White to move and mate in 2
[FEN "8/8/1p6/1P6/3k4/8/8/K7 w - - 0 1"]

In this problem, the goal is to determine the two moves (one for white and one for black) that led to the position shown. The solution is 1. bxa3+ Kd4 2. Kb2#
Henrik Juel: I do not understand this at all
It seems that ChatGPT is worthless for retro problems (2023-01-29)
A.Buchanan: Generally ChatGPT is amazing. We have entered a new age. Interacting with it reminds me of the first time I sent emails, or used a browser: we have crossed a frontier into engage with a function that will soon be commonplace. I already use it as a work tool for the last week. However it has limited skills and I was surprised it even attempted to construct a chess problem. It’s failure is humorous and kind of dreamlike (2023-01-30)
Henrik Juel: Thanks for your clarification, Andrew
ChatGPT is so amazing that it will give you a grade of B on some university exams; using it is obviously cheating, but do you enforce it?
In my youth calculators were developing fast; initially I banned the use of calculators in my OR exam, but the students were unhappy about it, saying that they were allowed in high school; I was forced to allow calculators, but then the poor students pointed out that the rich students had an unfair advantage; I then bought a few hundred cheap calculators and let the students borrow one for the exam (the rich students were still mad, but had to accept their lot in the social-democratic society of Danmark) (2023-01-30)
comment
Keywords: Joke, Kindergarten Problem, Minimal, Miniature
Genre: 2#, Retro
FEN: 8/8/1p6/1P6/3k4/8/8/K7
Reprints: Facebook 05/07/2023
Input: A.Buchanan, 2023-01-29
Last update: A.Buchanan, 2023-07-05 more...
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The problems of this query have been registered by the following contributors:

Gerd Wilts (9)
Frank Müller (3)
Mario Richter (2)
Erich Bartel (1)
A.Buchanan (9)
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