5. Zugzwang or Right to Move?
In order to avoid misunderstandings it is necessary to divide between the two terms zugzwang and right to move:.
Lets take a look on the game Carlsen,Magnus (2882) – So,Wesley (2776) [C54], Sinqueﬁeld Cup 7th Saint Louis (10), 27.08.2019, ChessBase Magazine Nr. 192. The next diagram shows the position after 35.c4. The comments are from Peter Heine Nielsen resp. Magnus Carlsen, and sorry, from Oops:
Carlsen,Magnus – So,Wesley
35. . . fxe4+
Peter Heine Nielsens comment: Facing reality, So alternates his plan, tries to complicate. The problem is, as Magnus happily explained after the game, that the fortress after 35...Kf6 36 g4 f4 37 Be1 g5 38 Bc3!
Carlsen,Magnus – So,Wesley: Analyse
has one problem: Yes, everything is solididly protected and White can do no harm to Black’s position on his own. But as Black is not allowed to pass, Zugzwang here plays its deadly consequence. Black has to make a move, and that makes his position instantly collapse. The rook needs to protect the b-pawn, but if it goes to b8, it allows Bxa5.
The knight on d6 is needed there to protect the rook on b7, else Bxa5 again is possible, and as the king is stuck on f6 protecting e5, and Black has run out of pawn moves, this is a pure and illustrative zugzwang. Black’s position will fall like a cardhouse, when removing one bit, will eventually make it all fall.
Oops comment: I can´t believe it. What does Magnus Carlsen mean? He (!) brought So into zugzwang? That doesn´t work. Or: He found himself in a favorable (!) zugzwang position after his 38-th move in the variant which started with 35...Kf6?
If the position after move 38 is a zugzwang position, than Carlsen has no more than a draw. Because someone, who beliefs to be in zugzwang, has a lost or drawn position, and his opponent - could he move - had at most a draw. For short:
Or the other way around: If So is with his 38. move in zugzwang, i.e. in a position of type (=/-) or (-/-), then Carlsen has no more than a draw! However he beliefs to be in a won position: But in chess there is no real position, where one side is winning and the other side is in zugzwang, unless we add winning positions to the class of zugzwang positions. That would make the term zugzwang obsolet. Is it by chance, that Oops thinks at Astrid Lindgrens Karlsson-on-the-Roof in this moment:
If you want to use both terms - zugzwang and right to move - side by side without contradictions, then you have to decide between zugzwang positions and won resp. lost positions.
In most cases neither masters nor amateurs are able to decide, in what kind of position they are playing. That is the exciting point in chess. But under these circumstances we should be carefull with terms like zugzwang, advantage, weakness, equality, etc. and with rules and principles, especially if we proof our statements with a lot of moves.
Carlsen or Nielsen: White can do no harm to Black’s position on his own.
Oops: For shure, that is correct. There is no winning move in chess without an error before!
Carlsen or Nielsen: Black has to make a move, and that makes his position instantly collapse.
Oops: The black position may already be lost. The move 31. Ne7 is a error candidate. It should be the aim of an analysis to prove this, or to find another faulty move - one half move is enough!
Carlsen or Nielsen: Zugzwang here plays its deadly consequence.
Oops: Nobody is able to put somebody into zugzwang. Zugzwang is the consequence of an error. But not every error leads to a zugzwang position.
Fazit: My goodness, somebody could answer: Is this not just splitting hairs? But that is not the deciding question. One should ask: What can we learn from the comments of masters, if they are not able - in a large number of cases - to proof, what they are saying?
List of examples