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1st October
2017

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2017





 
 
MatPlus.Net Forum Fairies Helpmate - Same solution, different motivation
 
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(1) Posted by Siegfried Hornecker [Tuesday, Sep 5, 2017 20:29]; edited by Siegfried Hornecker [17-09-05]

Helpmate - Same solution, different motivation


I see in FIDE Album 2010-2012 the following nice helpmate by Aleksandr Bulavka.

Queen symbol = Grasshopper
Knight symbol = Nightrider

(= 8+9 )

Aleksand Bulavka
Jubilee tourney Marek Kolčak 50 (2010), 1st prize
h#2
a) diagram
b) Kd3->e3
c) Kd3->e4

Solution:
1.Bc2 Ng6 2.Gf5 d:e6 mate.

Cyclic change of function of Black pieces' moves (interference, selfblock, un-attack)


Do you know of any other helpmates (fairy or not) with this theme? If so, please post them.

ITT: Helpmate twins with same solution but different motivation.
 
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(2) Posted by seetharaman kalyan [Tuesday, Sep 5, 2017 22:07]

Superb idea !
 
 
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(3) Posted by Juraj Lörinc [Tuesday, Sep 5, 2017 22:42]

M. Kolcak 50 had this as a required theme. Award is available in Marianka 2010 bulletin on page http://festival.soks.sk/bulletin-marianka-2010/ (see page 111 and following).

By chance, also the 2nd fairy prize (my own) made it into the same FIDE album (G48). :)

Marek has produced earlier at least two helpmates with the idea, one is here: http://jurajlorinc.com/chess/hmmobk14.htm#uloha3

The other has won 2nd Prize in Whisky in Turku 1995, based on the solving difficulty as well as beauty: http://www.yacpdb.org/#306512
 
   
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(4) Posted by Marko Klasinc [Wednesday, Sep 6, 2017 00:53]

My very good friend Matjaž Žigman, unfortunately too young deceased in 1992, published original with this idea 44 years ago.

Matjaž Žigman
Comm. Problem 1973
(= 5+8 )

h#2 b)Kh6-->a8 (=5+7)

1.Sb8 Bxh7 2.e4+ Bxe4 #
 
   
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(5) Posted by Jacques Rotenberg [Tuesday, Sep 19, 2017 02:32]

This illustrates very clearly what can be the limits of the idea of "weasels"
 
   
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(6) Posted by Hauke Reddmann [Tuesday, Sep 19, 2017 22:54]

Jacques, I'm no h# specialist and wanted to ask anyway -
what is the exact definition of a h# weasel? Does it relate
to the Necessary Weasel of TVTropes (with a Scott Adams
quote as reference) or to Morgensterns Poetic Weasel
(which is also necessary - for the rhyme)? Is it
identical to the German "Nachtwächter"?
 
   
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(7) Posted by Geoff Foster [Wednesday, Sep 20, 2017 06:27]

The h# weasel is discussed at length in "Black to Play", by Chris Feather.

http://juliasfairies.com/articles/black-to-play/

That book also has German text, but the link above is in English only.

Hauke is quite correct that the name weasel comes from a Morgensterns poem. Here is an excerpt from "Black to Play".


It is time we had a handy term for this. It was provided in an article by Alfred Gschwend in Schach-Echo in 1974. The BQ in the Molnár/Páros problem is a weasel. Of course, this is not meant as a term of abuse, since weasels are clearly quite cuddly carnivores; it originates in a poem by Christian Morgenstern which I translate (quite inaccurately) into English as follows:

A weasel
Sits at an easel
Painting with a teasel.

Do you know why
This sly
Beast thus wastes his time?

He does it so
(lf you must know)
My lines may have a rhyme.

Gschwend distinguishes three kinds of supplementary effects achievable with the aid of weasels, those of the sacrificial weasel, the symmetry weasel and the line closing weasel. The sacrificial weasel occurs in problems where a white piece is captured and consists in using a more powerful white piece than is necessary or perhaps in using a white piece where none is needed at all.
 
   
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(8) Posted by Siegfried Hornecker [Wednesday, Sep 20, 2017 12:17]

Of course this goes off-topic now, but the poem reminds me of a German one by the great Janosch:

Ich suche einen Reim
doch mir fällt keiner eim.

(roughly translated:
I'm looking for a rhyme
but there's none I can fime).
 
   
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(9) Posted by Harry Fougiaxis [Wednesday, Sep 20, 2017 19:31]

 QUOTE 
Gschwend distinguishes three kinds of supplementary effects achievable with the aid of weasels, those of the sacrificial weasel, the symmetry weasel and the line closing weasel. The sacrificial weasel occurs in problems where a white piece is captured and consists in using a more powerful white piece than is necessary or perhaps in using a white piece where none is needed at all.

Another very popular weasel used to be a white line piece pinning artificially a black piece that could be replaced with a less powerful unit whose pin is not necessary for the mate.
 
   
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(10) Posted by Jacques Rotenberg [Sunday, Sep 24, 2017 16:03]

not only a pinning line...
any line...
It seems that this word "artificial" is exactly the point.
It seems to me not so easy to declare what is "artificial" and what is not.
 
   
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(11) Posted by Jacques Rotenberg [Tuesday, Sep 26, 2017 01:48]; edited by Jacques Rotenberg [17-09-26]

a long and interesting debate about weasels already took place here :

http://www.matplus.net/start.php?px=1506423495&app=forum&act=posts&tid=177&fid=xshowh&page=0

the book of Feather - in a re-wrote version - can be found here :

http://juliasfairies.com/articles/black-to-play/

Chapter 2 page 10 point d) Motivation

I quote :
"...Once a composer has decided what moves he wishes to show he must find reasons why those moves will be the ones which solve the problem."...

This is a very surprising sentence : generally a composer does not wish to show a sequence of moves, he generally wants to show an idea, or a mechanism, or "something"...

Then, page 11, Feather introduces there the word "weasel" (seemingly created by Alfred Gschwend in 1974) and explains what it means for him. The interesting problem shown to illustrate it is the following :

Arpad Molnar
Special Pr
Magyar Sakkszövetség T.
(Sports committee of Budapest)
1967
(= 6+5 )
h#2

1.Rc3 Bf5 2.Rd3 Re4‡
1.Bd3 Rc6 2.Bc4 Bc5‡

I quote :
..."Bansac points out that the BQ is quite irrelevant in this connection, and might be removed from the board except that it is needed as a cookstopper. It is irrelevant in that the motivation it apparently brings to the moves 2.Rd3 and 2.Bc4 is unnecessary to make those moves happen. The need to block those squares would take care of that anyway."...

so... the black queen is a weasel...! (...and the problem should be discarded ?)

Well... this problem shows a nice set of interceptions by white and by black, with diagonal/orthogonal echo and model mates, exchange of functions between 6 pieces.
The black queen is of course essential and that it "is unnecessary to make those moves happen" is out of purpose here because the author wanted of course to show an idea, and not some "moves to happen"

This file about a sequence of moves that has completely different motivations is a very good example of what I mean : a problem is made to show an idea, not a sequence of moves.
 
   
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(12) Posted by Neal Turner [Friday, Sep 29, 2017 10:51]; edited by Neal Turner [17-09-29]

So Jacques, are you saying that if it wasn't needed as a cook-stopper it would still be desirable to have the bQ on the board?
 
   
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(13) Posted by Georgy Evseev [Saturday, Sep 30, 2017 09:43]

This is a very well known issue that may be called "redundant motive".

Like this: in a helpmate black move has two or more goals. The same set of goals is repeated in all lines of play.
Is it "good" if the problem is simplified by uniformly removing such extra motives? I do not know the answer...

The classic "redundant motive" is a combination Grimshaw+selfblock.
A random example is below.

Mikhail Sosedkin
Schach 1971
1 HM
(= 5+7 )

h‡2

1.Rb3 Bb1 2.Bc3 Se3‡
1.Bxb4 Bg1 2.Rc3 Sd2‡
 
   
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(14) Posted by Paz Einat [Saturday, Sep 30, 2017 14:19]

When there is a choice of which piece is to block on the intersection the Grinshaw effect, in my opinion, is acceptable. Otherwise, the main aim is the self-block and the interferences are more incidental.
 
   
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(15) Posted by Jacques Rotenberg [Monday, Oct 2, 2017 00:40]

@ Neal

Yes !!, the association of the white and black interceptions is a nice feature.
Look for comparison at the diagram proposed by Bansac :

Version Pierre Bansac
(= 6+4 )
h#2
1.Bd2 Rc5 2.Bc3 Bc4‡
1.Rc2 Bf4 2.Rd2 Re3‡

don't you feel something is missing ?

with this kind of logic you can go further and say that the interceptions of the black bishop and rook are 'artificial' too, they could be taken in the course of the solution instead of being intercepted, that could give a better economy in the mates and even in the diagram :

(= 6+3 )
h#2

1.Rd1 B×g3 2.Re1 Rf2‡
1.Be1 R×d5 2.Bd2 Bd3‡

how all that is bound to the original problem ? and how should this discard it ?
The author wanted blatantly to show interceptions, I can appreciate it "as is" and don't feel uncomfortable.

The example given by Georgy is interesting too : no 'weasel' but is it, for that reason, "better" than the Molnar ?
 
   
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(16) Posted by Jacques Rotenberg [Monday, Oct 2, 2017 02:33]; edited by Jacques Rotenberg [17-10-03]

btw I just discover the following :

Vitaly Medintsev
Idee und Form 2003
(= 7+2 )
h#2

1.Sb3 Rd6 2.Sd4 Bd5‡
1.Sf1 Bg5 2.Se3 Rf4‡

(the placing of the knight on d2 is "natural" for diagonal/orthogonal echo reasons, but it costs a pawn, this was possible :

(= 6+2 )
h#2

1.Sd5 Bg5 2.Se3 Rf4‡
1.Sc6 Rd7 2.Sd4 Bd5‡)

would you say this invalidates the Molnar ??
I don't think so...
 
   
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(17) Posted by Harri Hurme [Wednesday, Oct 11, 2017 19:01]

The Marek 50JT included also an orthodox H#2 section:

1.pr Hannu Harkola&Harri Hurme
(= 6+13 )

b)bKc5->h4
sol a&b 1.Rd4 Ne5 2.Nc2 Nxe4#
The point is the motivation for black move order, unpin but for a different piece. While two problems from the unorthodox section went into FA, none from the orthodox section.

Harri
 
   
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(18) Posted by Joost de Heer [Saturday, Oct 14, 2017 16:22]

One of the very few direct mates I've ever composed (my role was probably getting coffee though...)

Henk & Piet le Grand, Hans Uitenbroek, Joost de Heer
Quick composing Eretria 2005
(= 10+8 )

#2*

1... Se7 [Self-block] 2. Rd8#
1... Bd5 [Interference] 2. c5#

1. Sd5! [2.Ra6#]
1... Se7 [Interference] 2. Rd8#
1... Bd5 [Self-block] 2. c5#
[1... Rd5 2. Sf7#]
 
 
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MatPlus.Net Forum Fairies Helpmate - Same solution, different motivation