Answers.Body: <p>You may be thinking of what is known as &quot;reciprocal zugzwang&quot; which are positions where either side would stand worse for having the move. They are very common in endgames, and feature prominently in the fundamental strategies of King and pawn play.  Here is a simple example.</p>
  <pre><code>[FEN &quot;8/8/1p2k3/p3Pp2/P4K2/1P6/8/8 w - - 0 1&quot;]
  </code></pre>
  <p>Here is a more complex example.</p>
  <pre><code>[FEN &quot;6k1/8/8/5PPP/ppp5/8/8/1K6 w - - 0 1&quot;]
  </code></pre>
  
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Answers.Text: I get your first example, but can you give a brief overview of how having the first move is bad in the second example? It's not obvious, at least not to me :)
Answers.UserDisplayName: John D
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Answers.Text: The second position is actually pretty tricky, but basically the key is that the side *not* to move is in a perfect defensive position to meet any pawn thrust.  For instance, if White is to play, 1.f6 is met by 1...Kf7!, or 1.g6 is met by 1...Kg7!   Thus the side to move is essentially forced to compromise their king position or push a pawn that will then be immediately blocked.
Answers.UserDisplayName: John Chernoff
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Answers.UserDisplayName: John Chernoff
Answers.Body: <p>If we had enough computing power, every board state could be assigned a score recursively according to these rules:</p>
  <ol>
  <li><p>A win is 1 for the winning player and 0 for the losing player.</p>
  </li>
  <li><p>A draw is 0.5 for both players.</p>
  </li>
  <li><p>The score for the player whose move it is is the maximum of their scores among all their possible moves, and the other player's score is the minimum among those scores.</p>
  </li>
  </ol>
  <p>I'll rewrite your question so the players and moves are labeled:</p>
  <blockquote>
  <p>So in move N, White puts Black in zugzwang, and Black makes a move. However, after that move (that is, at move N+1), White doesn't have good moves either and it's a reverse zugzwang, or a self-zugzwang. Is it possible?</p>
  </blockquote>
  <p>If, at move N.5 (that is, the half-move after move N), Black has a move that puts White in a losing position, then Black's score for that move is 1. And since Black's score in a position where it's their turn to move is the maximum of their score among all their moves, and one of their moves has a score of 1, it follows that their score in that position is 1. But a (full) zugzwang, by definition, is a position where the player whose turn it is has a score of 0. So Black was not in zugzwang.</p>
  
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Answers.Text: This is useful and interesting +1
Answers.UserDisplayName: LeopardL GD
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Answers.Text: I have always fancied the idea that theoretically every position from the start has a score like you mention.
Answers.UserDisplayName: Michael
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Answers.Text: Note that such an exact definition also avoids sloppy use: Kf4 Pe5 - Ke6 Pf5 (Rewans position without the queenside pawns) easily gets called a reciprocal, but of course the game value is draw, even if the moving side loses a pawn.
Answers.UserDisplayName: Hauke Reddmann
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Answers.UserDisplayName: Acccumulation
Answers.Body: <p>Actually, what the poster describes is possible and not at all incompatible with the definition of zugzwang!</p>
  <p>To avoid all references to concrete positions, let us define:</p>
  <ul>
  <li>Full point zugzwang: If Black could pass this move, the position is won for Black. But any move loses for Black.</li>
  <li>Half point zugzwang 1: If Black could pass this move, the position is drawn for Black. Any move loses for Black.</li>
  <li>Half point zugzwang 2: If Black could pass this move, the position is won for Black. Any move draws for Black.</li>
  <li>White zugzwang: Just reverse colors.</li>
  </ul>
  <p>OK, now we just assume that White has one tempo move that puts Black into HPZ2, but lacks a second tempo move to turn HPZ2 to HPZ1. Thus the White tempo move avoids a loss, Black is in HPZ2, makes a move, White is in HPZ2 too since pass moves lack either, and game will be drawn.
  In that position, White also could have a move that actually wins, and thus putting Black in Zugzwang is a bad move. Observe:</p>
  <pre><code>[FEN &quot;8/8/p7/P2p1k1p/3P3P/5K2/P7/8 w KQkq - 0 1&quot;]
  </code></pre>
  <p>1.a4 HPZ1 for Black (passing wins), 1...Ke6! 2.Kf4 Kf6 HPZ1 for White (passing wins), drawn.
  Incidentally 1.a3! HPZ2, also puts Black in zugzwang and wins, as White has another tempo move. So in this case it was merely a &quot;wrong&quot; choice of zugzwang. It is easy to think of a position where White wins with PxP, but I'm too lazy to come up with one since I now have my first OTB game in years and must go :-)</p>
  
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Answers.Text: I don't understand your claim that `1. a4 pass` is a win for Black; it looks like draw to me.
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Answers.Text: I don't think this example is valid. Either side can easily draw no matter how many times the other side can pass; it's not very difficult to keep control over f4/f5.
Answers.UserDisplayName: D M
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Answers.Text: The example was done in a haste and IS invalid. I deleted the pawns that block the king's ways. Sorry!
Answers.UserDisplayName: Hauke Reddmann
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Answers.UserDisplayName: Hauke Reddmann
Answers.Body: <blockquote>
  <p>So a player puts another player in zugzwang, and the other player makes a move. However, after that move, the first player doesn't have good moves either and it's a reverse zugzwang, or a self-zugzwang. Is it possible?</p>
  </blockquote>
  <p>No. What you describe is incompatible with the definition of <a href="https://en.wikipedia.org/wiki/Zugzwang" rel="noreferrer">zugzwang</a>. By definition if you place your opponent in zugzwang then any move they can make is a bad one which gives you the advantage. If they have a good move which puts you in zugzwang then, by definition, your previous move was not a good move which put your opponent in zugzwang.</p>
  
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Answers.Text: I suppose you could have a case where the player put in zugzwang has to make a move which makes their position worse than if they didn't have to move, but is still in a good position (just not as good)
Answers.UserDisplayName: Cort Ammon
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Answers.UserDisplayName: Brian Towers
Body: <p>There's this related <a href="https://chess.stackexchange.com/questions/22240/helpful-zugzwang">Helpful Zugzwang?</a> but it's not quite what I am asking. I mean a double (or further) zugzwang.<br>
  So a player puts another player in zugzwang, and the other player makes a move. However, after that move, the first player doesn't have good moves either and it's a reverse zugzwang, or a self-zugzwang. Is it possible?</p>
  
Tags: <zugzwang>
Title: Can a zugzwang be a bad move?
ThreadText: # Can a zugzwang be a bad move?
  
  (Asked by: username_0 on 2021-06-25)
  
  There's this related [Helpful Zugzwang?](https://chess.stackexchange.com/questions/22240/helpful-zugzwang) but it's not quite what I am asking. I mean a double (or further) zugzwang.  
  So a player puts another player in zugzwang, and the other player makes a move. However, after that move, the first player doesn't have good moves either and it's a reverse zugzwang, or a self-zugzwang. Is it possible?
  
  **Tags:** zugzwang
  
  
  ---
  
  ## 4 answers
  
  ### Answer by username_8 on 2021-06-25. Score: 18 | Accepted answer
  
  > So a player puts another player in zugzwang, and the other player makes a move. However, after that move, the first player doesn't have good moves either and it's a reverse zugzwang, or a self-zugzwang. Is it possible?
  
  No. What you describe is incompatible with the definition of [zugzwang](https://en.wikipedia.org/wiki/Zugzwang). By definition if you place your opponent in zugzwang then any move they can make is a bad one which gives you the advantage. If they have a good move which puts you in zugzwang then, by definition, your previous move was not a good move which put your opponent in zugzwang.
  
  > **Comments:**
  > **username_9**: I suppose you could have a case where the player put in zugzwang has to make a move which makes their position worse than if they didn't have to move, but is still in a good position (just not as good)  
  
  ---
  
  ### Answer by username_1 on 2021-06-26. Score: 8
  
  You may be thinking of what is known as "reciprocal zugzwang" which are positions where either side would stand worse for having the move. They are very common in endgames, and feature prominently in the fundamental strategies of King and pawn play.  Here is a simple example.
  [FEN "8/8/1p2k3/p3Pp2/P4K2/1P6/8/8 w - - 0 1"]
  
  Here is a more complex example.
  [FEN "6k1/8/8/5PPP/ppp5/8/8/1K6 w - - 0 1"]
  
  > **Comments:**
  > **username_2**: I get your first example, but can you give a brief overview of how having the first move is bad in the second example? It's not obvious, at least not to me :)  
  > **username_1**: The second position is actually pretty tricky, but basically the key is that the side *not* to move is in a perfect defensive position to meet any pawn thrust.  For instance, if White is to play, 1.f6 is met by 1...Kf7!, or 1.g6 is met by 1...Kg7!   Thus the side to move is essentially forced to compromise their king position or push a pawn that will then be immediately blocked.  
  
  ---
  
  ### Answer by username_3 on 2021-06-26. Score: 4
  
  If we had enough computing power, every board state could be assigned a score recursively according to these rules:
  
  1. A win is 1 for the winning player and 0 for the losing player.
  2. A draw is 0.5 for both players.
  3. The score for the player whose move it is is the maximum of their scores among all their possible moves, and the other player's score is the minimum among those scores.
  
  I'll rewrite your question so the players and moves are labeled:
  
  > So in move N, White puts Black in zugzwang, and Black makes a move. However, after that move (that is, at move N+1), White doesn't have good moves either and it's a reverse zugzwang, or a self-zugzwang. Is it possible?
  
  If, at move N.5 (that is, the half-move after move N), Black has a move that puts White in a losing position, then Black's score for that move is 1. And since Black's score in a position where it's their turn to move is the maximum of their score among all their moves, and one of their moves has a score of 1, it follows that their score in that position is 1. But a (full) zugzwang, by definition, is a position where the player whose turn it is has a score of 0. So Black was not in zugzwang.
  
  > **Comments:**
  > **username_0**: This is useful and interesting +1  
  > **username_4**: I have always fancied the idea that theoretically every position from the start has a score like you mention.  
  > **username_5**: Note that such an exact definition also avoids sloppy use: Kf4 Pe5 - Ke6 Pf5 (Rewans position without the queenside pawns) easily gets called a reciprocal, but of course the game value is draw, even if the moving side loses a pawn.  
  
  ---
  
  ### Answer by username_5 on 2021-06-26. Score: 3
  
  Actually, what the poster describes is possible and not at all incompatible with the definition of zugzwang!
  To avoid all references to concrete positions, let us define:
  
  Full point zugzwang: If Black could pass this move, the position is won for Black. But any move loses for Black.
  Half point zugzwang 1: If Black could pass this move, the position is drawn for Black. Any move loses for Black.
  Half point zugzwang 2: If Black could pass this move, the position is won for Black. Any move draws for Black.
  White zugzwang: Just reverse colors.
  
  OK, now we just assume that White has one tempo move that puts Black into HPZ2, but lacks a second tempo move to turn HPZ2 to HPZ1. Thus the White tempo move avoids a loss, Black is in HPZ2, makes a move, White is in HPZ2 too since pass moves lack either, and game will be drawn.
  In that position, White also could have a move that actually wins, and thus putting Black in Zugzwang is a bad move. Observe:
  [FEN "8/8/p7/P2p1k1p/3P3P/5K2/P7/8 w KQkq - 0 1"]
  
  1.a4 HPZ1 for Black (passing wins), 1...Ke6! 2.Kf4 Kf6 HPZ1 for White (passing wins), drawn.
  Incidentally 1.a3! HPZ2, also puts Black in zugzwang and wins, as White has another tempo move. So in this case it was merely a "wrong" choice of zugzwang. It is easy to think of a position where White wins with PxP, but I'm too lazy to come up with one since I now have my first OTB game in years and must go :-)
  
  > **Comments:**
  > **username_6**: I don't understand your claim that `1. a4 pass` is a win for Black; it looks like draw to me.  
  > **username_7**: I don't think this example is valid. Either side can easily draw no matter how many times the other side can pass; it's not very difficult to keep control over f4/f5.  
  > **username_5**: The example was done in a haste and IS invalid. I deleted the pawns that block the king's ways. Sorry!  
  
  ---
  
  