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MatPlus.Net Forum Threemovers More Nth degree black corrections in 3#
 
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(61) Posted by Miodrag Mladenović [Monday, Jul 18, 2016 16:51]

@Shankar
Great definition. I also completely agree with your explanation of errors.

@George
It's not possible even to count black errors. There are samples where multiple black errors are repeated through the play. But we cannot count them as two errors to increase the degree of correction. Like it's possible that black thematic defensive move at the same time closes a line and abandoning guard of some square. But it's only important that all further thematic defenses are repeating both errors. I'll try to find some sample and to post it here.
 
   
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(62) Posted by Georgy Evseev [Tuesday, Jul 19, 2016 08:17]

OK, I have done my homework and found that I was wrong.

According to current set of definitions there no so such things as "secondary correction".
There is "primary correction" and then a direct jump to "tertiary correction" according to Velimirovic/Valtonen Encyclopedia.
 
   
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(63) Posted by Frank Richter [Tuesday, Jul 19, 2016 12:46]

Seems to be that german terminology is more useful here: "fortgesetzte Verteidigung" resp. "Verteidigung N-ten Grades", poorly translated by me as "advanced (continued) defence" resp. "Nth degree defence". So the counted degree refers to the current defence and not to those degree of correction.

Interesting discussion, by the way.
 
   
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(64) Posted by shankar ram [Wednesday, Jul 20, 2016 16:19]; edited by shankar ram [16-07-20]

Though the title of this thread refers to 3-movers, I can't resist quoting a recent Fairy Chess Two mover, which won laurels, both in its tourney and in the recent WCCI. To repeat a commonly used phrase: "it will repay close study"!
So, let's dig in.

Hubert Gockel,
1st Prize,
M.Caillaud 50-JT, 2014
(= 10+11 )

S#2
3 Solutions
Functionary Chess

In Functionary Chess, a piece can move/capture/check only if it is attacked/guarded by an enemy piece. In the diagram position, neither K is in check.. because both BSg3 and WBd6 are not attacked by enemy pieces!

1.Qb5!(zz)
1...Bb7(~) a 2.h5(zz), Kg5# A
1...Bd5! b 2.Sd3+, exd3# B
1...Bc6!! c 2.Qxf5+, Kxf5# C

1.Qc8!(zz)
1...Bd5(~) b 2.h5(zz), Kg5# A
1...Bc6! c 2.Sd3+, exd3# B
1...Bb7!! a 2.Qxf5+, Kxf5# C

1.Qf7!(zz)
1...Bc6(~) c 2.h5(zz), Kg5# A
1...Bb7! a 2.Sd3+, exd3# B
1...Bd5!! b 2.Qxf5+, Kxf5# C

After each of the 3 keys:
2.h5? B~!
2.Sd3+? exd3+ 3.b7!
2.Qxf5+??(illegal)

Primary Defence motive: Since this is a zugzwang problem, there is no primary defence motive
Primary Error(A): BB moving away from a8 where it is attacked by WR/WQ, thereby immobilising itself and forcing BK to move after 2.h5(zz), Kg5#

Secondary Defence motive: BB moving to a fresh square, where it is (re)attacked by WQ, thereby keeping it mobile: 2.h5? B~!
Secondary Error(B): BB moving to square, where it is attacked by WQ PLUS prevention or invalidation of 3.b7 as a defence to 2.Sd3+,exd3# (by closing the a8-h1 line). Note that both errors are required for 2.Sd3+, exd3# to work.

Tertiary defence motive: Making the WQ mobile by attacking it (Now WQ can capture BB or interpose on b7-h1 line after 2.Sd3+, exd3+)
Tertiary error(C): Making the WQ mobile by attacking it, thereby allowing 2.Qxf5+ Kxf5#

As explained above, the W reply after each type of B move is always the same. But, after each key, the nature of the 3 BB moves to b7/c6/d5 is cycled between primary/secondary/tertiary. This results in a 3x3 Lacny! I have also written the solution differently (as compared to a "normal" 3x3 Lacny) to highlight this.

A wonderful synthesis of 3 different themes: Tertiary correction, Lacny theme and very fairy specific Functionary Chess effects. The change is brought about very simply by the different positions of the WQ in each phase.

I think a study of the cycling mechanism in this problem will help in a better understanding of correction in general! The errors have to be defined as shown to explain the primary/secondary/tertiary relationship.
 
   
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(65) Posted by Miodrag Mladenović [Wednesday, Jul 20, 2016 16:30]

@Shankar
I am assuming that instead of 2.g5(zz), it should be 2.h5(zz),
 
   
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(66) Posted by shankar ram [Wednesday, Jul 20, 2016 17:13]; edited by shankar ram [16-07-20]

Miodrag, Right you are! Corrected.
 
   
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(67) Posted by ichai [Thursday, Jul 21, 2016 00:29]

There is something that is not completely clear here for me, for example, you write :

1.Qb5!(zz)
1...Bb7(~) a 2.h5(zz), Kg5# A
1...Bd5! b 2.Sd3+, exd3# B
1...Bc6!! c 2.Qxf5+, Kxf5# C

I translate :
1...Bb7 nullifies b6-b7 (and get paralysed)
1...Bd5! nullifies b6-b7 and get active
1...Bc6!! nullifies b6-b7 and get active and activates the wQ

but it seems to me that you could write also for the two first moves :
1...Bd5 (~) nullifies b6-b7
1...Bb7! nullifies b6-b7 and get paralysed
but then the third move would not find its place in the chain.

in any case, I can see 1...Bd5 as a correction of 1...Bb7 or 1...Bb7 as a correction of Bd5

where is my mistake ?
 
   
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(68) Posted by shankar ram [Thursday, Jul 21, 2016 10:31]

ichai..

After 1.Qb5!, 1..Bb7 contains the error of "nullify b6-b7". But this error alone is not sufficient for allowing 2.Sd3+, exd3#. An additional error of "moving to attacked square" is also required. Therefore the presence of the error "nullify b6-b7" is not significant for 1..Bb7.

However, 1..Bd5 does contain this additional error and therefore allows 2.Sd3+, exd3#

And since, 1..Bc6 contains both these errors, it does continue the chain.

Your doubt of whether 1..Bb7 and 1..Bd5 are corrections of each other is valid. In that case, they would become a pair of dual avoidance variations and 1..Bc6 would be a correction(2nd degree) of both.

I too had such a doubt. However, I analysed further and concluded that a tertiary sequence exists and wrote out the errors specifically to justify it.
 
   
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(69) Posted by Nikola Predrag [Thursday, Jul 21, 2016 12:50]

The post-key play indeed creates a neat cyclic content. However, it would be honest to present it as hs#1.5 with the twins (after the 3 keys) and possibly better economy.
What is gained by "faking" a selfmate genre? The keys are horrible, reducing Black's legal possibilities from initial 11 to only 3!
In a genuine "antagonistic genre", the key should not illegalize black moves but prepare White to ANSWER the initially possible black moves.
That's why a checking key is a flaw (in principle) - it heavily reduces the legal black play, turning it partially into the help-play.
(Checking key could actually be even a good one, if bK is the only mobile black piece, for instance:
wQc7,bKd5; 1.Qd8+; check is not a flaw here, White wastes a move to double the legal black possibilities from 3 to 6!)

The immobilization of bBd4 & bPf7 by the keys shows a heavy disrespect and misuse of the selfmate's nature for the sake of "Lacny". A master should present an idea with a convincing respect to the medium of realization. I may accept it as hs#1.5 (as mentioned above).
 
   
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(70) Posted by ichai [Thursday, Jul 21, 2016 13:39]

Your critics are a bit harsh ?
s# is more usual than hs#.
And the problem seems very very clever.
I don'f feel the keys are bad. On the opposite, I like them, you have to choose the good places for the queen.... not so easy!
 
   
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(71) Posted by ichai [Thursday, Jul 21, 2016 14:01]

@ Shankar :

"1..Bc6 would be a correction (2nd degree) of both."

It is a 2nd degree for one and a 3rd degree for the other, no ?
 
   
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(72) Posted by Nikola Predrag [Thursday, Jul 21, 2016 16:10]

s# is more usual???
I don't think that a BAD s# should become more "usual" than a GOOD hs#.
The main purpose of the keys is to completely eliminate 8 out of 11 black moves. And not much choice is left, how many wQ's moves do fulfill the main purpose, out of all possible white moves?
If you don't move the pieces randomly, but with the idea to allow only bBa8 to move, there are 4 wQ's moves. It's easier to guess a key then to fail. :-)
 
 
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(73) Posted by shankar ram [Thursday, Jul 21, 2016 16:54]

Ichai..
>"1..Bc6 would be a correction (2nd degree) of both."

>It is a 2nd degree for one and a 3rd degree for the other, no ?

If we agree that 1..Bb7 is the primary defence, then 1..Bd5 is the secondary defence and 1..Bc6 is the tertiary.
If we consider that 1..Bb7 and 1..Bd5 are BOTH primary (with dual avoidance), then 1..Bc6 would be a common secondary defence to both.
 
   
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(74) Posted by shankar ram [Thursday, Jul 21, 2016 17:02]

Nikola..

Your suggestion to recast the problem as a hs#1.5 is interesting. But I don't know if speaking of "correction" in a help play problem would be meaningful. We would have to coin a different name!

Your criticism of the strong keys: well.. I would generally agree.. but in this setting, with this particular fairy condition, it looks difficult to avoid. Maybe, the fact that Black is left with only 3 moves makes it easier to notice and to understand both the correction and Lacny patterns.
 
   
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(75) Posted by Juraj Lörinc [Thursday, Jul 21, 2016 18:05]

Actually nowadays hs# in general are much more frequent than s#. If we talk about quality, good problems of both types are becoming more rare than a few years ago. Selfmates absolutely, due to the fact that they are much less frequently than before. Helpselfmates relatively, due to the fact that a lot of published hs# are bad problems, with little valuable content shown.

If I should choose between s#2 and hs#1,5 forms, as suggested by Nikola, I would definitely go with s#2. There is fight side against side in s#2, zugzwang being the important element of the fight, while twinning for hs#1,5 would be mere technical exercise with such a short stipulation in hs# genre.

As regards quality of the problem in s#2 form, at least three grandmasters of different upbringins agreed that it is at least a good problem, with WCCI judges confirming: H. Gockel composed it and sent to M. Caillaud's JT, Michel awarded it with the first prize and P. Gvozdjak quoted it in a very positive tone a few times. Then WCCI judges marked it with 11 points. You might call this logical fallacy by appeal to authority, but if so many different people with different tastes agree the problem is very good, most probably it really is very good. (I also agree.)

s# genre is surely not faked here.
 
   
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(76) Posted by ichai [Thursday, Jul 21, 2016 19:35]

Shankar,

If I go on the same way I began, it gives :
1...Bd5 (~) nullifies b6-b7
1...Bb7! nullifies b6-b7 and get paralysed.
1...Bc6! nullifies b6-b7 and activates the wQ.
So both 1...Bb7 and 1...Bc6 look like corrections (2nd degree) of 1...Bd5
 
 
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(77) Posted by Nikola Predrag [Thursday, Jul 21, 2016 20:35]

Well Shankar, I mainly question the principles in general and not a particular problem (which I just "misuse" as an example for the questioned principles).
The Hubert's problem is a masterpiece when I comprehend the content as of a hs#1.5. I don't question the author's choice of genre for this particular case, for it just follows the "common standards". I ask "why and how have our community and the experts come to accept and encourage the serious flaws as a common standard?"

3 Zugzwang solutions, what makes it crucially different to the help-play?
And the whole story about the "corrections" is only virtual, so it would equally make a content in hs# genre.
Without a threat, Black is not motivated to move and without a relation "purpose-error", there are just the EFFECTS of the purposeless moves.
All these effects would be present in hs#1.5 and we would be able to see the "gradual corrective" component in them.
Actually in hs#, bB's moves would be MOTIVATED to help, with "corrective graduation of triple-avoidance effects".
hs#2, with each of the 3 twins marked as 0.3.1.1.

The great challenge is to make hs#2, 3.3.1.1., starting with wQ's moves as in s#2.
 
 
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(78) Posted by Nikola Predrag [Thursday, Jul 21, 2016 21:08]

Juraj, the keys are horribly bad, especially the way how BRUTALLY they achieve exactly the Zugzwang. If you and all the experts do not understand the nature of the genre, that's entirely your problem.
But it seems that you&experts don't care for the very medium you create in. Sometimes it looks even as detesting the "foolish old criteria".
Any "excuse" might be allowed to make the composing easier.

s# genre surely IS faked here, illegalizing 8 out of 11 moves proves it.
It's a question whether hs#1.5 would indeed be better, and I primarily care about the content.
My question is about the principles which are continuously being corrupted to suit the "easy way" approach.
Well, that was quite enough from me, don't take my harshness too seriously. My intention is to wake some re-consideration of the forgotten principles which make the basis for various "modern" conventions :-)
 
   
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(79) Posted by ichai [Thursday, Jul 21, 2016 23:42]

Nikola,
All the file here is about correction and it is interesting and difficult.
Aestetics is not the point (perhaps aesthetics of correction would be relevant)
For other matters please, open a new file.
 
   
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(80) Posted by Nikola Predrag [Friday, Jul 22, 2016 02:27]

ichai,
perhaps you are missing the point. You must be familiar with a medium before you could comprehend the idea and how it is realized in that medium. And there is the whole trouble, perceiving only a pattern abstracted from the medium could be delusive if we forget what generates the thematic play.
My questioning is not about the genre alone, but about how the black correction is related to the stipulation. I've mentioned it briefly in post No.77.

If I have no respect for a certain medium, I simply should not (mis)use it.
I can write in the "Alphabet medium": a/A-b/B-c/C,a/B-b/C-c/A,a/C-b/A-c/B and there's "Lacny".
Of course, there is quite enough of complex chess-geometry and chess effects in Gockel's work to make a true chess problem, but..!
The stipulation claims that Black OPPOSES in 1st move (as a thematically relevant feature) which apparently results with errors and corrections.
The combination of three features makes it unconvincing - the keys, the Zugzwang and the multiple solutions.
Each of them alone whispers that the crucial thematic move B1 could be seen as a help-play rather than "opposing play". And all 3 features together loudly shout about that.

So, what is claimed as an error, could be seen as a useful and corrected help, and what is claimed as a correction could be seen as an anti-dualistic (harmful) effect. In 3 degrees.

s#2 with 2 tries an 1 solution would at least offer 2 refutations as a sign of opposition and resistance.
Anyway, it's all about the corrections, you may believe it or not.
 
   
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MatPlus.Net Forum Threemovers More Nth degree black corrections in 3#