No.587 Stephan Dietrich (Germany) |
Original Problems, Julia’s Fairies – 2014 (II): May – August →Previous ; →Next ; →List 2014(II) Please send your original fairy problems to: julia@juliasfairies.com |
No.587 by Stephan Dietrich – An aristocratic Miniature with two fairy conditions! (JV)
Definitions:
Functionary Chess: A piece can move only if it is threatened.
Annan Chess: Units move normally except when they are standing one square directly in front of another unit of the same color, when they move with the power of the rear unit. In the starting position, all pawns (black & white) move with the power of the piece behind them, e.g. 1. Pc2xh7 (as bishop).
No.587 Stephan Dietrich |
Solution: (click to show/hide) |
white Kh1 Sf1 Be1
black Kh3 Sg2 Rf5
hs#3 b) wSf1→g4 (3+3) |
In the final position, why white cannot play 4.Kg1?
Is it a bug in Popeye? If you consider just Functionary Chess, then the wK is not threatened and so cannot move. However when combined with Annan Chess the wK actually is threatened (which is why it is mate!). It would be good to test the problem with WinChloe, but does it support Functionary Chess?
Thanks Geoff Foster. Since I have not worked on either of these two fairy conditions, I thought that I was missing some point of the problem.
Yes it supports, and actually the problem is C+ WinChloe.
Is that a bug in Winchloe also? Is the problem sound ?
The question is whether or not wKh1 is observed by bKg3. Both programs answer is it not, so wKh1 is paralized and hence checkmated because attacked by bKg3 (thanks to the Annan condition).
This is a matter a convention, but there is some underlying logic here: The condition Annan tells that bKg3 is moving like a Knight, not that it is a Knight… So one may argue that wKh1 is not observed “directly” by bKg3 (although it is attacked by bKg3 equipped with Knight power)… Saying otherwise, it seems that, for both programs, “observation” is taken in the orthodox sense.
Oh sorry, please forget my previous post, this is nonsense! In Annan chess things are going the other way for black. Thus in the final position of a) the wKh1 is threatened by bSg2 moving as a King! (not by bKg3 moving as a Knight)… Hence it is clear why wKh1 can’t play to g1.
Btw note that bKg3 is not threatened by wBe1 as this Bishop is no more observed by bSg2, this latter moving now as a King…
Thanks. I was confused as which one is the front piece. This seems to differ for white and black !
Yes! A good trick concerning the Annan condition is to remember that, in the initial game array, Pawn moves are fairy (either black or white)…
So in the mate of a), bK moves as R but this is not transferred to bSg2 which moves as bK, checking wK and guarding g1&h2?
It seems so 🙂 So, the King is still King temporarily moving like rook !
Yes, with vertical black pieces ABC, C is moving like B (and not like A although B is moving like A).
The complete definition of Annan (or Southern) Chess: A unit (incl.King) one square in front of a friendly unit moves in the manner of the rear unit, not as itself. For White, affected units are on the same file and one rank higher, for Black they are one rank lower. Transference of powers is only to the next unit: with 3 friendly units adjacent in a file, the 3rd moves as the 2nd, the 2nd moves as the 1st and the 1st is unaffected. A white Pawn on the first rank is immobile.