How to solve defensive retractors under the condition of AntiCirce

by Günther Weeth, Stuttgart

Shortly after the fabulous start of that successful story of the Proca retractor under the condition of AntiCirce Wolfgang Dittmann dealt with the question of how to approach that new type as a solver. He laid down a summary of methods that might pave the way to the solution of problems of that kind in two articles: Die Schwalbe, vol. 204, December 2003, “Lösungsstrategien im Verteidigungsrückzüger mit Anticirce-Bedingung”) and – as a supplement – in Die Schwalbe, vol. 207, June 2004 where he provides valuable information concerning the testing program “Pacemaker” established by Thomas Kolkmeyer. Since then the fairy condition of “AntiCirce” has not only stood its ground in the field of the Proca retractor but also in a wider range of retro problems. The new type has been welcomed by a small number of highly motivated solvers, even so by such solvers being somewhat reluctant to tackle it in the first two or three years of its existence. →The Article (PDF, 8 pages)

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Laco Packa
January 18, 2016 12:30

Question: for testing the correctness of AntiCirce retractors is used Pacemaker program. Where it can be bought or freely downloaded?

shankar ram
January 18, 2016 16:30

I asked this question earlier. Seems like it’s not publicly available yet… for love or money! 😉

Laco Packa
January 25, 2016 09:22

The first diagram should be referred to as a condition Anti Circe Cheylan. Otherwise it is part Hoeg incorrect, 1.Kd2xSd1! refutes.

Laco Packa
January 25, 2016 09:25
Reply to  Laco Packa

Sorry, 1.Kd2xSe1!, of course.

Nikola Predrag
January 25, 2016 13:58

What is an exact definition of “Hoeg”?
The short one looks as being ambiguous about “if”:
“…In Hoeg Retractors the opposite side decides, IF and what man was uncaptured….”

White retracts 1.Kd2-e1! What does that mean?
White determines from which square wK has departed and to which square it has arrived, but White can’t claim that this move was NOT a capture.
OK, White moves (retracts) wK from e1 to d2 and BLACK adds bSe1.
If Black may claim that 1.Kd2-e1 was actually 1.Kd2xSe1, why Black wouldn’t claim that 1.Kd2-e1 was actually 1.Kd2xPd3(Ke1)?, and add bPd3?

Vlaicu Crisan
January 25, 2016 22:20

@Nikola: Curiously, you are not the only one to make this confusion! I asked the same questions and Klaus Wenda has kindly provided very clear and convincing explanations.

Please read the definitions given in the article KLAN-Defensive Retractor – see https://juliasfairies.com/wp-content/uploads/WendaThoma-KLAN-Aufsatz-Engl.pdf.

The key sentence is:
In the case of White retracting a move, it is up to him to define both the starting square and the arrival square (provided that there is no other unambiguous prescription given on grounds of legality according to the convention of retro chess).

Klaus also underlines: when White in Hoeg-type uncaptures a black unit it is his right to define both squares: the square from which the uncapture is starting, as well as the square on which the uncaptured piece is placed. Black has only the right to decide what kind of sacrificial object is chosen.

@Laco: It seems you are right, in the first diagram should actually be AntiCirce Cheylan, otherwise black may put a bS on e1.

Nikola Predrag
January 26, 2016 04:00

Thanks Vlaicu for that link, I thought that there was a more complete definition on the site but I couldn’t find it.

Unfortunately, that definition is still not complete:
“…In the case of White retracting a move, it is up to him to define both the starting square and the arrival square……Now it is Black who decides whether that move is an uncapture or not, and -in the affirmative case- defines the kind of black sacrificial unit to be chosen, …”

Where did you find:
“…Klaus also underlines: when White in Hoeg-type uncaptures a black unit it is his right to define both squares: the square from which the uncapture is starting, as well as the square on which the uncaptured piece is placed. Black has only the right to decide what kind of sacrificial object is chosen…”?
(I found something similar, as “further clarification”, only about KLAN type.)

It’s a bit strange way of “completing” a retro-move,
1. White tells about the departure square, then
2. Black tells about the capture, then
3. White tells about the square of capture…

When does actually Black tell about which piece was captured, before or after point 3.?

Anyway, that should be written in the definition.

seetharaman
January 26, 2016 15:46

If Black may claim that 1.Kd2-e1 was actually 1.Kd2xSe1, why Black wouldn’t claim that 1.Kd2-e1 was actually 1.Kd2xPd3(Ke1)?, and add bPd3?>>>>>>
This was Nikola’s original question. As a beginner my understanding is that black has the choice of claiming either of the two or any other capture like 1.Kd2xQe3 (Ke1) or claim no capture.

Nikola Predrag
January 26, 2016 16:59

Well, Black can’t claim that the last move was 1.Kd2xQe3(Ke1) because there would be no previous black move (“undoing” the double check to wKd2).

Klaus Wenda has clarified it to Vlaicu (privately?) but that should be published within the definition:
“when White in Hoeg-type uncaptures a black unit it is his right to define both squares: the square from which the uncapture is starting, AS WELL AS THE SQUARE ON WHICH THE UNCAPTURED PIECE IS PLACED. Black has only the right to decide what kind of sacrificial object is chosen.”

It’s quite a peculiar sequence of making a retro-move complete, 1st part is White’s, 2nd part is Black’s and 3rd part is agan White’s.
And it has to be guessed that when Black chooses that the retro-move was an uncapture, he must immediately decide what kind of sacrificial object is chosen (or, may Black decide this after the White’s choice of square of the capture?).

seetharaman
January 26, 2016 20:15
Reply to  Nikola Predrag

“Well, Black can’t claim that the last move was 1.Kd2xQe3(Ke1) because there would be no previous black move (“undoing” the double check to wKd2).” —– Sorry Nikola, I meant my comment for a general situation. You are right that it is not applicable to the above quoted problem. I simply did not realise that you were discussing with reference to this specific problem.

Vlaicu Crisan
January 26, 2016 19:30

In Hoeg Retractor, White decides first the departure and arrival square, while Black decides only what piece was captured on the arrival square, if any. This is actually the precise order in the retraction process.
Therefore the 1st and 2nd parts belong to White and the 3rd part belongs to Black.

Nikola Predrag
January 27, 2016 02:37

Vlaicu, I understand the intention and the practice but the given definition doesn’t say so.
Your last post would explain the orthodox captures but an AntiCirce capture is not only about departure&arrival, there’s 3rd square involved.

Do you perhaps mean that the square of capture is the “arrival” square and the rebirth square is just an automatic consequence of the rules.
This would mean that in the mentioned problem, White might retract 1.Kd2-d3(Ke1), where d3 is the “arrival” square, and the rebirth on e1 would automatically mean that something was captured on d3 (even if there were no black Rs d4&d5).
If that is the case, then Black may decide only about a capture/noncapture on a rebirth square (and only in “Calvet”).

There must be something essential that I don’t understand well 🙁

Laco Packa
January 27, 2016 09:49
Reply to  Nikola Predrag

Nikola:
It is necessary to respect the legality of the move. Capture may be necessary parts of legality and it may also apply to orthodox chess. A well known example: Kd3 – Re5, Bc5. Last retracted move Ke3-d3 is legal, but starts a forced sequence of moves 1.Ke3xPd3 e4xPd3 ep 2.d2-d4
In this case it is irrelevant whether Proca or Hoeg.
By you referenced move Kd2xd3 (Ke1) is also legal and capturing (P, S, B – not Q or R) is its (necessarily) legal part. But it is not the correct key …

Nikola Predrag
January 27, 2016 15:05

Laco, I know that all.
I don’t understand the definition of Hoeg retractor when it is applied to AntiCirce.

In Cheylan type, how do you apply the part:

“…Now it is BLACK who decides whether that move is an uncapture or not…”

Just give an example.

Laco Packa
January 27, 2016 15:21
Reply to  Nikola Predrag

In the type Cheylan you can not uncapture from rebirth square, that’s all. In our case, therefore, the white king dont need to fear that after a retract from e1 there may appear black officer.
For type Calvet would be possible refutation 1.Kd2xSe1 Sd3-e1+! and black would not be forced to uncapture d3x (Q) e2.

Nikola Predrag
January 27, 2016 16:48

I have asked a simple question about BLACK’s DECISION whether a white retro-move was an uncapture or not.
The answer is necessary for understanding the exact nature of Hoeg retractor.

It’s also necessary to define what are the meanings of “depature”/”arrival” square in the rules.
One of these squares is not correctly interpreted in the Hoeg-rules.

Therefore, the given Hoeg-definition is both incomplete and incorrect.
The problems in the articles are beautiful but to see what happens, one must “invent” his own Hoeg-definition which would conveniently explain the play.

I believe that it should be reversed, first the exact rules and then the play.

And the mistake about the type (Calvet/Cheylan), in the mentioned Wenda’s miniature, is very probably caused by the incompleteness and incorrectness of the definition when it is applied to AntiCirce.

Laco Packa
January 27, 2016 17:15
Reply to  Nikola Predrag

Nikola, I probably understand what you mean. Decision “uncapture or nothing” is at anticirce (Hoeg retractor) partially limited. For example, when white retracting Ka5-e1 it is obvious that last move was uncapture even without the “permission” of black. OK, but it’s elementary logic used fairy conditions – anticirce! It does not benefit any party, because the rules apply equally to white and black.
This can be interpreted as we wish, we can disagree, we can argue. But that is all what we can do :))

Nikola Predrag
January 27, 2016 17:51

We surely can do something better – to define the AntiCirce retractor EXACTLY, denying any “as we wish” interpretation.

For the beginning, which are the squares of departure/arrival/capture, when retracting 1.Ka5xb6(Ke1)?

Which of these squares White may DECIDE about?

Also we can insert (into the definition) some clear rule which would rule out the following interpretation:
White retracts 1.Kd2-e1 but Black may decide that this retro-move is an uncapture (according to the present definition) and thus REFUTE the White’s TRY.

What in the present definition might rule out such a refutation?

Laco Packa
January 27, 2016 19:56
Reply to  Nikola Predrag

I think the anticirce retractors are defined exactly and accurately enough. How could otherwise exist the program testing their correctness?
The case, which remember, is without definition “Cheylan” cooked, not refuted. The reason is the existence of a Kd2xSe1 !, which allows only version Calvet.

Vlaicu Crisan
January 27, 2016 19:54

Let’s not forget Hoeg Retractor appeared before AntiCirce was invented. The original definition may be preserved “as is”, but you are right we need to explain the whole mechanism when the move involves more than two squares.

Referring to your example 1.Ka5xb6(Ke1):
– e1 is the rebirth square
– a5 is the departure square
– b6 is the arrival square
White decides first the departure and arrival square and Black then decides what piece was captured on the arrival square. This principle is applicable also when the arrival square and the rebirth square are the same.

However, when Black may not claim a capture occurred on the arrival square, due to illegality reasons, he is not entitled to leave a piece.

Bearing in mind the above restriction, in the case of the retraction of 1.Kd2-e1 in AntiCirce Cheylan Black is not allowed to put a piece on the arrival square (e1), because this square is also the rebirth square. According to the rules of AntiCirce Cheylan the captures on the rebirth squares are illegal, so that’s why Black may not leave a piece on e1.

Nikola Predrag
January 27, 2016 22:31

@Laco
I don’t see a cook, after 1.Kd2xSe1 Se1-d3.
Interesting, it’s YOU who has pointed to that REFUTATION
(January 25, 2016 at 09:22, with a corrected move in the next post and January 27, 2016 at 15:21) 🙂

@Vlaicu
Your interpretation of the “arrival” would mean that in an orthodox Hoeg retractor, which “…appeared before AntiCirce was invented…”, WHITE MAY NOT DECIDE about the arrival square (since it’s known before any retraction).
And that’s contradictory to the Hoeg definition “as it is”.

In case of AntiCirce, White MIGHT decide about the arrival ONLY if he WOULD uncapture in that retro-move and if that uncapture would NOT happen on the rebirth square of the respective white piece.

And you repeat “explaining” me what I’m not asking (since it’s perfectly clear, like “Cheylan=no capture on the rebirth square”).
I say that in “Cheylan”, BLACK NEVER decides whether a white retro-move is an uncapture or not (on the contrary, WHITE ALWAYS decides about that in his own retro-move).
And that is exactly the opposite to the most fundamental property of “Hoeg” nature.

Even in “Calvet”, in a white retro-move, Black might decide yes/no only about uncapture on a rebirth square, ANY OTHER uncapture is decided by White.

But if nobody sees the essential troubles with the given definition and “as we wish” interpretations, that’s OK, I’m not interested in it any more.

Laco Packa
January 28, 2016 13:03
Reply to  Nikola Predrag

Nikola: I tried to follow the rules you suggested and have composed such a little thing. I would like to dedicate this to you.

W: Kc1, Pa3, b5, d3, h2 (5)
B: Ke8 (1)
Defensive retractor type Hoeg (rules designed by NP) , -2 & +1#
Anticirce Calvet
2 solutions
I. 1.Kd1-c1! zz (uncapture is impossible)
1. … Ka4xQa5 –>e8 (White may decide about uncapture (yes/not), the square of capture and type of the captured piece.)
2.Qa8-a5 & 2.Kd1-c2#
The second solution probably does not need a comment.
II. 1.a2-a3! Ka1xQb2–>e8 2.Qe2-b2 & 2.Qe2-e5#

Unfortunately, the correctness can not be checked …

Nikola Predrag
January 28, 2016 14:47

Laco, it’s not that I suggest the rules, it’s about what the given rules suggest:

Black retracts – BLACK decides from which square his piece has departed and WHITE decides whether that retro-move is an uncapture or not.

In your example, Black would not decide that bK has departed from a4 or a1, but from some OTHER square. White might decide whether THAT OTHER retro-move is an uncapture or not. The point is that White may not decide about the departure of a black piece in a black retro-move.

Solving program applies a certain definition. As you might have seen in some comments on this very website, a program’s definition is not always in accordance with the genuine definition (or with some other solving program).

A program should apply the genuine rules, and if a programmer changes the rules, he becomes the inventor of a “brand new type” and that should be mentioned in the name of these new set of rules.
There are already some “Popeye-types” and “Winchloe-types”.

Laco Packa
January 28, 2016 20:52
Reply to  Nikola Predrag

The rules are neither good nor bad – they are a matter of compromise and consensus. If I do not like the method of the Knights movement and regard it as illogical, so what can I do?
However, I would like to ask a question. In the article are two examples of Hoeg retractor. Which particular move used in them can be considered incorrect or illogical?

Nikola Predrag
January 29, 2016 01:36

A rule is exact and unambiguous. Otherwise, it’s not a rule, since the interpretation would depend on various personal beliefs and prejudices.

Why should I say something about Wenda’s miniature, IT’S YOU who has said it is incorrect and Vlaicu has agreed.

If you can confirm that the original publication in Die Schwalbe was of “Cheylan-type”, there would still remain the unclear meaning of “arrival square”.

Orthodox chess is clear, before the move a piece stands on the departure square and when the move is completed, it stands on the arrival square.
The “arrival effect” of some move usually refers to the square occupied by some piece after the move was completed, even in (Anti)Circe.

Where is a clear definition of the “arrival square”?
And what is the meaning of “…Now it is Black who decides whether that move is an uncapture or not…”, in case of “Cheylan-type”?

False statements make the rules unclear.

Laco Packa
January 29, 2016 08:43
Reply to  Nikola Predrag

You did not answer the question.

Nikola Predrag
January 29, 2016 11:28

It’s not about a particular problem but about the unclear rules.

But YES, I HAVE ANSWERED that it was YOU who had informed us about INCORRECT twin b)

Do I really have to explain what means “incorrect” or “unsound”?
Move 1…Pd3xQe2(Pe2-e7) is not a defensive move and the problem is a defensive retractor. Is this correct and logical to you?

Laco Packa
January 29, 2016 12:13

Move 1…Pd3xQe2(Pe2-e7) is a defensive move . And it’s the ONLY defensive move in the position. Or maybe you know another way to protect white king against check?
About incorrectness of the first problem, I wrote:
“The first diagram should be referred to as a condition Anti Circe Cheylan. OTHERVISE is part Hoeg incorrect, 1.Kd2xSd1! refutes.”
I think it is not incorrectness, but the author’s forgetfulness or inattention.

Nikola Predrag
January 29, 2016 19:07

You have asked about the article and I have answered.
Your comment is not in the article.
And anyway, you are not entitled to change the author’s original.
I have also said that you may check in Die Schwalbe how exactly the problem was originally published, perhaps the reproduction in the article is just a simple mistake.

And even if the author’s intention was indeed type Cheylan, I still don’t see the definition clearly.
And I have answered even about the type Cheylan on January 25, 2016 at 13:58.
You should first read that and then you might understand why I insist on defining the “arrival”.

So, what is the purpose of your post on January 29, 2016 at 08:43 ??

Read carefully what was said, to see at least what I’m talking about, before you comment it.

Laco Packa
January 29, 2016 19:53
Reply to  Nikola Predrag

I looked in Die Schwalbe and found that the “Cheylan” really in the article is missing. Which means that my first remark was probably correct.
I asked you, however, several questions that you have not answered. Why?

Nikola Predrag
January 29, 2016 22:24

Laco, which questions? I’ve found 3:
1. How could otherwise exist the program testing their correctness?
ANSWERED, January 28, 2016 at 14:47

2. If I do not like the method of the Knights movement and regard it as illogical, so what can I do?
ANSWERED, January 29, 2016 at 01:36

Actually, I didn’t answer the question in your very first post. Sorry, I didn’t know it was for me, my answer is “I have no idea”.

Was there any other question?

3. In the article are two examples of Hoeg retractor. Which particular move used in them can be considered incorrect or illogical?
ANSWERED by YOU!!! – and I have mentioned that, not once, and AGAIN NOW FOR THE LAST TIME!!!
I don’t accept you torture with repeated questions WHICH WERE ANSWERED!!!

4. Or maybe you know another way to protect white king against check?
READ January 25, 2016 at 13:58
Black decides that White retro-move is the uncapture of:
a)bP, b)bB, c)bS, d)bR
and the full solution (which is missing) would at least have a dual in b).

Laco Packa
January 30, 2016 10:02
Reply to  Nikola Predrag

I do not think I’m the one who tortures you.
In this debate it has been said enough. It would be underestimating the reader if we thought that he could not form their own opinion on the issue.

Nikola Predrag
January 30, 2016 14:52

Yes, the given rule is not clear. The article gives:

**in type Hoeg it is the opposite colour that decides whether the next (legal) retro move is an uncapture or not and what kind of unit is going to be uncaptured**

A reader/solver FIRST reads the rule and THEN applies it.
How and why would a reader conclude that **…** is a LIE?

February 2, 2016 21:05

Concerning my example A:
Laco P is right, the restriction Anticirce Cheylan is necessary to
ensure the intended solution in b). White must not uncapture Kd2:Xe1!
The Problem is published in Schwalbe 276/2015, no.16565 with the condition Anticirce CHEYLAN!

Klaus Wenda

February 6, 2016 19:11

An excellent English overview on Hoeg defensive retractor with Anticirce condition you may find just her:

On the other hand, I think Vlaicu excellently described the single steps of an Hoeg retraction move with Anticirce; see his post here dated 27.01.2016, 19:54)