No.1544
Neal Turner
(Finland)
Original Fairy problems
JF-2020-II:
01.07.2020 - 31.12.2020
| pieces | 'Royal piece', 'Grasshopper(G)' | фигуры |
| Grasshopper(G): | Moves along Q-lines over another unit of either color to the square immediately beyond that unit. A capture may be made on arrival, but the hurdle is not affected. | Ходит по линиям ферзя, только перешагивая через другую фигуру любого цвета, на поле, следующее сразу за этой фигурой. Взятие может быть только на поле прибытия, фигура-препятствие остается незатронутой. |
| Royal piece: | Piece that executes a function of the King on the board. | Фигура, которая выполняет на доске функцию короля. |
| conditions | 'SAT' | условия |
| SAT: | A King is under check if it can move to at least one square not controlled by the opposite side. | Король находится под шахом в случае, если он может пойти хотя бы на одно поле, не контролируемое стороной противника. |
No. 1544 Neal Turner
Finland
original - 19.09.2020
SAT
Royal Grasshopper f4, b6
Solution: (click to show/hide)
(C- by Popeye & WinChloe !!!)
So we feature Nietvelt Defences – a black piece self-pins in anticipation of being unpinned in the threat. White changes course, taking advantage of the pin.
Here we have a type of pinning specific to this fairy combination.
We note the square d4 is observed by both kings, and that moving either of the hurdles on c5 or e4 would be check.
So any black piece sitting on e4 will be pinned.
But Black notices that the threat move 2.Se6+ puts a guard on d4, which would free the e4 piece.
After 1..Sxe4 2.Se6+ Black blocks with 2..Sf6+ and now with the bishop's line opened we have 3.Bf5.
After 1..Bxe4 2.Se6+ the bishop can simply defend by going to c6 or f5.
This is all very nice, but the computer says No!
Noting the royalgrasshoppers on the board, the programs want to play 1..f2-f1=G and after 2.Se6+ we have 2..Gf5.
I think I've mentioned this tendency earlier, and of course usually it has no significance.
But here it's threatening the very existence of the problem, so in reply to the computer the composer says No, No, No! We don't accept it.
(Anybody interested in seeing more examples of pinning strategies with this condition can check out the latest issue Juraj's e-zone Conflictio No.27 on the Articles page on this site.)
The both programs, Popeye and WinChloe, show no solution with the refutation 1…f2-f1=G !
The question if promotion to G is correct while there’s only Royal G on the board? Myself I’d rather agree with solving programs here, seeing Royalty as behavior/property of the fairy piece G. The same way I’d expect promotion to white or black G if having Halfneutral G or HurdleColourChanging G on the board. But if there’re any described rules about it?
Interesting if promotion into normal Grasshopper would work for recently invented by Petko Petkov Grasshopper BUL (well, not obligatory Grasshopper, of course)?
On the other hand, if there’s one of Chameleon pieces (the property) on the board, the promotion into any of S,B,R,Q-Chameleon piece is possible. Looks like any of pieces who can have Chameleon behavior. The same time, while any piece can have HalfNeutral behavior, only fairy pieces presented on the board can be used for the promotion (to white, black, halfneutral).
So, I’d formulate it as the primary criteria for the promotion is the presence of the fairy piece, and the secondary criteria is the property, but to be applied only to either any orthodoxal or to fairy piece existing on the board.
Many of the fairy conditions can also be imagined or defined as attributes (behaviour). For instance we have Circe pieces (instead of Circe chess). Similarly Madrasi pieces.. Actually it is an interesting possibility.
But I agree with Julia that Royal is an attribute to a fairy piece, so promotion is allowed
We use the expression ‘Royal Grasshopper’ meaning a grasshopper with royal attributes, but this is just a convention that’s taken hold. We could just as easily refer to a ‘Grasshopper King’ – a royal piece with grasshopper attributes. This is in fact my preferred designation, using an inverted king as its symbol (notice how I refer to them as ‘kings’ in the commentary). Looking at it from this point of view, promoting to a G doesn’t make any sense.
Yes the problem is C- and it is perfectly normal on my opinion…
But if you add “no promotion on fairy pieces” (available on Winchloe) it is C+ !
But it is a big weakness of construction…
Allways un my opinion, the author should find a solution without this additional condition.
Neal is the author and he says there are actually 2 (w+b) ‘Grasshopper Kings’ on the board. In chess, there are no additional ‘non-royal’ Kings, and here, there are no additional ‘non-royal’ ‘Grasshopper Kings’. (In Marine chess, there are no additional ‘non-royal’ Poseidons.)
C- could mean that ‘Grasshopper King’ is perhaps not yet programmed, although such concept of a single ‘Fairy King’ per side is closer to the nature of Chess than a royal piece with additional ‘non-royal’ siblings.
The only difference between Grasshopper Kings and Royal Grasshoppers is that the former does not allow promotion to G. This means that “Grasshopper King” actually is programmed, because it can be tested by using Royal Grasshoppers plus an additional constraint. For example, in Popeye: “condition PromOnly Q R B S”.
The need of an ‘additional constraint’ suggests that “Grasshopper King” is actually NOT programmed. Do you need an ‘additional constraint’ to exclude promotions into ordinary (non-royal) Poseidons or neutral Kings?
And beside “Grasshopper King”, various types of fairy pieces may be on the board with respective promotions allowed (not only Q R B S).
‘Fairy King’ (or ‘fairy Pawn) is not just a ‘fairy piece’!
Do you need an ‘additional constraint’ to exclude promotions into Berolina Pawns?
If a royal Pawn is just a ‘fairy piece’, can you promote a Pawn into a non-royal fairy Pawn (Dummy)?
There is a pretty standard understanding of Kings and Pawns, and a ‘fairy King’ should have a default meaning, without an ‘additional constraint’ needed.
I’m sorry, this discussion looks to me as a completely upside-down approach, starting from a ‘computer’s view’ (whatever that could possibly mean???).
What I meant was that “Grasshopper Kings” can be put below the diagram and the problem can still be regarded as C+, because it has been tested with Royal Grasshoppers and another constraint. With Popeye the other constraint is “PromOnly Q R B S”. Obviously if the diagram had any non-royal fairy pieces then those fairy pieces would have to be added to the PromOnly statement. It is not necessary for Grasshopper Kings to be added to the solving program, especially as it would have to be done all over again for “Grasshopper Lions”, etc.
Yes, that’s practical simplification for this one particular case.
However, a general principle should extend the orthodox rules, allowing a choice of KING’s altered moving abilities (as a Grasshopper, Lion, Bishop…), beside the (orthodox) default.
So, for a fairy King you choose King and add e.g. Lion as the moving ability (and not a Lion, adding the royal attributes as for a royal piece).
This could mean that the starting square of a fairy King remains e1(e8), even preserving the castling rights. And some other alterations of orthodox chess could be interesting. For instance, King moving like a Grasshopper and Knights moving like a Nightrider but not actually treated like fairy pieces (as being promoted), e.g. regarding rebirth squares etc..