Answers.Body: <p>First of all, your plan of keeping White's queenside blocked doesn't quite work out in any case: After e.g. <strong>1...c4 2. Qe2 Qc7 3. b3 b5</strong> White can simply continue attacking your pawn chain by <strong>4. a4</strong> and you cannot answer <strong>4...a6</strong> because of <strong>5. axb5 axb5? 6. Rxa8</strong>. 
  If you try to protect the rook by <strong>2...Qc6</strong>, White can insert <strong>3. Ne5</strong> to displace the queen. </p>
  
  <p>But even if White does not play a4, there are some things to note:</p>
  
  <ul>
  <li>The blockade is not complete anyways, as the Bc1 can always escape
  its own pawn chain via a3.</li>
  <li>The move <strong>1...c4</strong> is very committal, <strong>1...e6</strong>
  on the other hand keeps all options open and even adds some more by
  supporting the development of your kingside. Crucially, you can now
  answer <strong>dxc5</strong> by <strong>Bxc5</strong>, and since e3 would become super weak,
  White is discouraged to take on c5 anytime soon. The option of
  playing <strong>...c4</strong> thus won't disappear after <strong>1...e6</strong>!</li>
  <li>But in the meantime, the pawn keeps up pressure on the White centre from c5, pressure that an immediate <strong>...c4</strong> loses.</li>
  <li>In this light, you'd like your queen to stay on b6, too, where she eyes
  both the g1-a7 diagonal as well as b2.</li>
  </ul>
  
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Answers.Body: <p>Some points:</p>
  
  <p>White's "bad" bishop is already locked behind their pawns, your move doesn't change that, it's a feature of the opening white is playing. Long term white could go for <code>Bc1-d2-e1-h4</code>, or play <code>b3</code> and <code>Ba3</code>. In fact in your proposed line of <code>1...c4 Qc2 2.Qc6 3.b3 b5</code>, white has <code>4.Ba3</code>. Note that if you don't play <code>...c4, Ba3</code> sometimes fails to <code>...cxd4 cxd4 Bxa3 Nxa3 Qa5+</code> picking up the knight, but if you play <code>...c4</code> white doesn't have to think about that possibility.</p>
  
  <pre><code> [title "4.Ba3"]
   [fen "rn2kb1r/pp2pppp/1q3n2/2pp4/3P1P2/2PQPN2/PP4PP/RNB1K2R b - - 0 1"]
  
   1...c4 2.Qc2 Qc6 3.b3 b5 4.Ba3
  </code></pre>
  
  <p>Similarly, your "good" bishop is already good. But it doesn't gain much from <code>...c4</code>.</p>
  
  <p>You have a good square on <code>e4</code>, but if you put a knight there then white will exchange it for his and there will be a pawn on that square. If white plays <code>Ne5</code> and you exchange it, they can take <code>fxe5</code> and get an attack over the f-file.</p>
  
  <p>You removed the tension (white doesn't have to care about the option <code>...cxd4</code> anymore) and now have few good pawn breaks (I don't think <code>...f6</code> and <code>...e5</code> is going to work soon). If one the other hand white manages <code>e3-e4</code>, then your pawn on <code>c4</code> may become weak. Or white can attack it with <code>b3</code> and <code>a4</code>. Or go for a kingside attack with <code>g2-g4</code>.</p>
  
  <p>So I don't see your points. That said, <code>0.7</code> is more of an advantage than I had expected, maybe there is a way for them to force you to waste some more time, or win a pawn?</p>
  
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Answers.UserDisplayName: RemcoGerlich
Answers.Body: <p>The other answers were great, but I think you could sum it up like this :
  the player who has built the stonewall is looking for a locked center so that he can benefit from the time to build up an attack on your king, funneling his pieces over in the vicinity of your king without having to worry about central counter-play.</p>
  
  <p>Doing c4 might superficially look like gaining space, but it really helps the opponent in keeping the center locked, by giving up a possible break which might be needed.</p>
  
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Answers.UserDisplayName: Andrew Brooks
Answers.Body: <p>...c4 is generally bad because it releases the tension on White's d4-pawn. This makes it much easier for White to get away with pushing e4, since the e3-pawn doesn't need to support the d4-pawn anymore.</p>
  
  <p>You're correct that White does have a weak hole on e4, but after playing Qc2 and Nbd2, he's ready to push e4 and gain a central initiative.</p>
  
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Answers.Body: <p>It is slow. At a time you should be developing and getting the rest of your pieces out, you play c4, meaning that eventually to get your standard play with b5-b4, you will need to finish your development, then move your queen again, and only then get in b5-b4. That gives time for white to do a lot of different things, depending on how you develop. You will also have to take the time to play Ne4 almost immediately so you can play f5 since if white gets in e4 first, that is also going to be super advantageous to him.</p>
  
  <p>It is a common mistake to change the base of the pawn structure in the opening, slowing one's play.</p>
  
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Answers.UserDisplayName: PhishMaster
Answers.Body: <p>Good question! The positional priorities in this position do not really lie in whose bishop has more prospects, but rather in the emerging pawn structure, potential pawn breaks, and either side's ability to create targets and holes in opponent's camp. </p>
  
  <p>In short, <code>c4</code> here is an extremely committal move which should only be played if it can be backed by very strong concrete ideas, which do not exist in this position. Why does the fact that it's committal makes it into a poor choice? It's simply because it resolves white's strategy into something immediate and concrete, namely: to undermine black's pawn chain and create a weak pawn out of <code>c4</code>, and to this end, the almost immediate <code>e4</code> pawn break is perfectly playable for white without any drawbacks and black has nearly no means of preventing it. So in hindsight, moves such as <code>c4</code> and similar ones in analogous positions, are only good if you are sure you can stop your opponent's relevant pawn breaks. Otherwise you're creating overly advanced pawns that will eventually turn into weaknesses that you cannot easily parry. 
  Remember, a pawn is considered to be weak if (all 3 must be met simultaneously):</p>
  
  <ul>
  <li>it <strong>cannot</strong> move</li>
  <li>it is <strong>isolated</strong> (not defensible by pawns)</li>
  <li>it <strong>can be</strong> attacked. </li>
  </ul>
  
  <p>To summarise: with the unavoidable <code>e4</code> by white and <code>a4</code> in reply to <code>b5</code>, the <code>c4</code> pawn is bound to become a weakness as it meets all 3 said conditions. 
  Gained tempi and temporarily blocked out bishops are secondary in such positions, unless you have an actual threat following your pawn push (such as, an imminent knight jump to <code>d3</code>!)</p>
  
  <p>More concretely, let's take a look at a few possible continuations as illustrated in the following diagrams:</p>
  
  <p><strong>Left:</strong> Early <code>e4</code> by white  |  <strong>mid:</strong> early <code>b5</code> attempt  |  <strong>right:</strong> <code>e4</code> blockade attempt</p>
  
  <p><a href="https://i.sstatic.net/yEY5Zb.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/yEY5Zb.png" alt="enter image description here"></a>
  <a href="https://i.sstatic.net/AKARPb.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/AKARPb.png" alt="enter image description here"></a>
  <a href="https://i.sstatic.net/0Lxzab.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/0Lxzab.png" alt="enter image description here"></a></p>
  
  <ul>
  <li><p>Left: Immediately undermining <code>c4</code>'s defense after <code>Qe2, Nbd2</code>, if black takes, <code>c4</code> is dropping soon and both knights will be well established centrally. And if black tries to sit still, <code>e4-e5</code> is a threat, leaving black's kingside heavily undefended and white's pawn push is quite straightforward, black will lack space and the ability to create a counter-attack.</p></li>
  <li><p>Mid: Black prepares for the immediate <code>b5</code> (with <code>Qc7</code>) in order to reinforce <code>c4</code> which leads to: <code>Qe2, Qc7, Nbd2, e6, e4, b5, f5!</code> and soon followed by <code>a4.</code> Notice how white's perfectly undermining the entire pawn backbone (<code>e6, d5, b5</code>) of <code>c4</code>.</p></li>
  <li><p>Right: Black simply tries to stop <code>e4</code> by blockading it with a knight, but since it cannot really be followed up by <code>f5</code> (as shown in the diagram), it will easily be challenged with <code>Nbd2</code> after which black either has to take on <code>d2</code> which revives <code>e4</code> again, or lets white take on <code>e4</code> leaving a ton of light square weaknesses behind along with a permanent knight post on <code>e5.</code> Note that in this structure, black has no prospect for ever landing a knight on <code>d3</code>, leaving the light square control that the overly advanced pawns have secured virtually unusable. Finally, notice that in neither of these cases, black's left with any form of initiative or targets in white's structure to allow for any counter-attack. </p></li>
  </ul>
  
  <p>Lastly, by not playing <code>c4</code>, you can still entertain a timely resolution of the central pawns in order to either simplify or create weak points in white's centre. And to connect with our discussions, by holding still with the pawn on <code>c5</code> you are actually stopping white's <code>e4</code> push as after, say, <code>e6, Nbd2, Be7, e4</code> you can simply take both on <code>e4</code> and <code>d4</code> not allowing white any central control (unlike the case of <code>c4</code> where white always had clear spatial advantage), and your structure is devoid of weaknesses. If anything, white will be the only side with potential dark square weaknesses. And if white recaptures on <code>d4</code> with the pawn, then it's a comfortable IQP structure with easy play for black.</p>
  
  <p><a href="https://i.sstatic.net/wEMvvb.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/wEMvvb.png" alt="enter image description here"></a></p>
  
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Answers.Text: Much better answer than mine! I like how your answer is all about the pawns and hardly mentions the bishops at all, that hits the nail on the head. And nice diagrams :-)
Answers.UserDisplayName: RemcoGerlich
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Answers.Text: What's your basis for claiming that a pawn can't be considered weak unless it's isolated, attacked and blocked? You write as if "weak" is some kind of technical term with a precise definition, but it isn't: it's just a general concept of not being very good.
Answers.UserDisplayName: David Richerby
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Answers.Text: @DavidRicherby oh it's as you may have guessed merely an empirical categorization of what it means to qualify the *state* of a pawn as *weak,* but given chess barely lends itself to absolute generalizations, all such rules may break down depending on the context. If you will, practically speaking, it's nearly impossible to imagine a position where there's a pawn satisfying those conditions and in actuality not being weak, i.e. not dropping in near future. So as far as such definitions go, it's reasonably complete. Often, once either condition isn't met, there's chance to "unweaken" the pawn.
Answers.UserDisplayName: Ellie
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Answers.Text: @Phonon I agree that an isolated, attacked, blocked pawn is a weakness. But you're claiming that being isolated, attacked and blocked is the _only_ way a pawn can be weak.
Answers.UserDisplayName: David Richerby
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Answers.Text: @DavidRicherby Just a small parenthesis, it's rather "attackable" not necessarily already under attack, that is, opponent is able to target the presumed pawn if desired. As for whether it's the *only* way, let's just say I don't know of other cases, exclusive to these conditions, where a pawn would still be considered weak. :) 
  It's just a way to put the usual observations into 3 concrete concepts. For instance the 3rd one (blockaded), if not being met, then the pawn can often move and potentially be got rid of (through some liquidation/trades).
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Body: <p>I made a horrible decision as black in a game, and I do not understand why it's incorrect.</p>
  
  <pre><code>[fen "rn2kb1r/pp2pppp/1q3n2/2pp4/3P1P2/2PQPN2/PP4PP/RNB1K2R b - - 0 1"]
  </code></pre>
  
  <p>I played c4, Stockfish considers the position to be + 0.4 after the move. My reasoning: I forever block white's bad bishop behind his blocked pawns, while keeping my good bishop. Since I gain a tempo on the queen, I can move my queen right away to be able to answer the break b3 with b5. </p>
  
  <p>I am also thinking that my position is much better, as white has a hole on e4 and I don't have such a weakness, so I thought I'd capitalize on my advantage by closing up the position. </p>
  
  <p>Stockfish considers this move to be a really poor move, e6 leading to an evaluation of -0.7. </p>
  
  <p>I've had this several time, and it's unclear to me why my move is bad, even though it gives me an inferior position from a superior one.</p>
  
  <p>Is it always bad to close up the position this way, or is it specific to the position ? Why is it bad, because I forever lose my main pawn break ? Or because my "good bishop" has no target and is therefore not really good ? </p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2020-01-09T09:45:15.787Z
Comments.Text: Just because Stockfish changes a number, it doesn't mean you made a "terrible mistake"
Comments.UserDisplayName: David
Tags: <strategy><positional-play><closed-position><bad-bishop>
Title: Assessing an early c4 against white's Stonewall structure
ThreadText: # Assessing an early c4 against white's Stonewall structure
  
  (Asked by: username_0 on 2019-02-07)
  
  I made a horrible decision as black in a game, and I do not understand why it's incorrect.
  [fen "rn2kb1r/pp2pppp/1q3n2/2pp4/3P1P2/2PQPN2/PP4PP/RNB1K2R b - - 0 1"]
  
  I played c4, Stockfish considers the position to be + 0.4 after the move. My reasoning: I forever block white's bad bishop behind his blocked pawns, while keeping my good bishop. Since I gain a tempo on the queen, I can move my queen right away to be able to answer the break b3 with b5. 
  I am also thinking that my position is much better, as white has a hole on e4 and I don't have such a weakness, so I thought I'd capitalize on my advantage by closing up the position. 
  Stockfish considers this move to be a really poor move, e6 leading to an evaluation of -0.7. 
  I've had this several time, and it's unclear to me why my move is bad, even though it gives me an inferior position from a superior one.
  Is it always bad to close up the position this way, or is it specific to the position ? Why is it bad, because I forever lose my main pawn break ? Or because my "good bishop" has no target and is therefore not really good ?
  
  **Tags:** strategy, positional-play, closed-position, bad-bishop
  
  > **Comments:**
  > **username_1**: Just because Stockfish changes a number, it doesn't mean you made a "terrible mistake"  
  
  ---
  
  ## 6 answers
  
  ### Answer by username_7 on 2019-02-07. Score: 18 | Accepted answer
  
  Good question! The positional priorities in this position do not really lie in whose bishop has more prospects, but rather in the emerging pawn structure, potential pawn breaks, and either side's ability to create targets and holes in opponent's camp.
  
  In short, `c4` here is an extremely committal move which should only be played if it can be backed by very strong concrete ideas, which do not exist in this position. Why does the fact that it's committal makes it into a poor choice? It's simply because it resolves white's strategy into something immediate and concrete, namely: to undermine black's pawn chain and create a weak pawn out of `c4`, and to this end, the almost immediate `e4` pawn break is perfectly playable for white without any drawbacks and black has nearly no means of preventing it. So in hindsight, moves such as `c4` and similar ones in analogous positions, are only good if you are sure you can stop your opponent's relevant pawn breaks. Otherwise you're creating overly advanced pawns that will eventually turn into weaknesses that you cannot easily parry.
  Remember, a pawn is considered to be weak if (all 3 must be met simultaneously):
  
  * it **cannot** move
  * it is **isolated** (not defensible by pawns)
  * it **can be** attacked.
  
  To summarise: with the unavoidable `e4` by white and `a4` in reply to `b5`, the `c4` pawn is bound to become a weakness as it meets all 3 said conditions.
  Gained tempi and temporarily blocked out bishops are secondary in such positions, unless you have an actual threat following your pawn push (such as, an imminent knight jump to `d3`!)
  
  More concretely, let's take a look at a few possible continuations as illustrated in the following diagrams:
  
  **Left:** Early `e4` by white | **mid:** early `b5` attempt | **right:** `e4` blockade attempt
  
  [![enter image description here](https://i.sstatic.net/yEY5Zb.png)](https://i.sstatic.net/yEY5Zb.png)
  [![enter image description here](https://i.sstatic.net/AKARPb.png)](https://i.sstatic.net/AKARPb.png)
  [![enter image description here](https://i.sstatic.net/0Lxzab.png)](https://i.sstatic.net/0Lxzab.png)
  
  * Left: Immediately undermining `c4`'s defense after `Qe2, Nbd2`, if black takes, `c4` is dropping soon and both knights will be well established centrally. And if black tries to sit still, `e4-e5` is a threat, leaving black's kingside heavily undefended and white's pawn push is quite straightforward, black will lack space and the ability to create a counter-attack.
  * Mid: Black prepares for the immediate `b5` (with `Qc7`) in order to reinforce `c4` which leads to: `Qe2, Qc7, Nbd2, e6, e4, b5, f5!` and soon followed by `a4.` Notice how white's perfectly undermining the entire pawn backbone (`e6, d5, b5`) of `c4`.
  * Right: Black simply tries to stop `e4` by blockading it with a knight, but since it cannot really be followed up by `f5` (as shown in the diagram), it will easily be challenged with `Nbd2` after which black either has to take on `d2` which revives `e4` again, or lets white take on `e4` leaving a ton of light square weaknesses behind along with a permanent knight post on `e5.` Note that in this structure, black has no prospect for ever landing a knight on `d3`, leaving the light square control that the overly advanced pawns have secured virtually unusable. Finally, notice that in neither of these cases, black's left with any form of initiative or targets in white's structure to allow for any counter-attack.
  
  Lastly, by not playing `c4`, you can still entertain a timely resolution of the central pawns in order to either simplify or create weak points in white's centre. And to connect with our discussions, by holding still with the pawn on `c5` you are actually stopping white's `e4` push as after, say, `e6, Nbd2, Be7, e4` you can simply take both on `e4` and `d4` not allowing white any central control (unlike the case of `c4` where white always had clear spatial advantage), and your structure is devoid of weaknesses. If anything, white will be the only side with potential dark square weaknesses. And if white recaptures on `d4` with the pawn, then it's a comfortable IQP structure with easy play for black.
  
  [![enter image description here](https://i.sstatic.net/wEMvvb.png)](https://i.sstatic.net/wEMvvb.png)
  
  > **Comments:**
  > **username_3**: Much better answer than mine! I like how your answer is all about the pawns and hardly mentions the bishops at all, that hits the nail on the head. And nice diagrams :-)  
  > **username_8**: What's your basis for claiming that a pawn can't be considered weak unless it's isolated, attacked and blocked? You write as if "weak" is some kind of technical term with a precise definition, but it isn't: it's just a general concept of not being very good.  
  > **username_7**: @username_1Richerby oh it's as you may have guessed merely an empirical categorization of what it means to qualify the *state* of a pawn as *weak,* but given chess barely lends itself to absolute generalizations, all such rules may break down depending on the context. If you will, practically speaking, it's nearly impossible to imagine a position where there's a pawn satisfying those conditions and in actuality not being weak, i.e. not dropping in near future. So as far as such definitions go, it's reasonably complete. Often, once either condition isn't met, there's chance to "unweaken" the pawn.  
  > **username_8**: @Phonon I agree that an isolated, attacked, blocked pawn is a weakness. But you're claiming that being isolated, attacked and blocked is the _only_ way a pawn can be weak.  
  > **username_7**: @username_1Richerby Just a small parenthesis, it's rather "attackable" not necessarily already under attack, that is, opponent is able to target the presumed pawn if desired. As for whether it's the *only* way, let's just say I don't know of other cases, exclusive to these conditions, where a pawn would still be considered weak. :)  It's just a way to put the usual observations into 3 concrete concepts. For instance the 3rd one (blockaded), if not being met, then the pawn can often move and potentially be got rid of (through some liquidation/trades).  
  
  ---
  
  ### Answer by username_2 on 2019-02-07. Score: 10
  
  First of all, your plan of keeping White's queenside blocked doesn't quite work out in any case: After e.g. **1...c4 2. Qe2 Qc7 3. b3 b5** White can simply continue attacking your pawn chain by **4. a4** and you cannot answer **4...a6** because of **5. axb5 axb5? 6. Rxa8**.
  If you try to protect the rook by **2...Qc6**, White can insert **3. Ne5** to displace the queen.
  
  But even if White does not play a4, there are some things to note:
  
  * The blockade is not complete anyways, as the Bc1 can always escape
    its own pawn chain via a3.
  * The move **1...c4** is very committal, **1...e6**
    on the other hand keeps all options open and even adds some more by
    supporting the development of your kingside. Crucially, you can now
    answer **dxc5** by **Bxc5**, and since e3 would become super weak,
    White is discouraged to take on c5 anytime soon. The option of
    playing **...c4** thus won't disappear after **1...e6**!
  * But in the meantime, the pawn keeps up pressure on the White centre from c5, pressure that an immediate **...c4** loses.
  * In this light, you'd like your queen to stay on b6, too, where she eyes
    both the g1-a7 diagonal as well as b2.
  
  
  ---
  
  ### Answer by username_3 on 2019-02-07. Score: 8
  
  Some points:
  White's "bad" bishop is already locked behind their pawns, your move doesn't change that, it's a feature of the opening white is playing. Long term white could go for Bc1-d2-e1-h4, or play b3 and Ba3. In fact in your proposed line of 1...c4 Qc2 2.Qc6 3.b3 b5, white has 4.Ba3. Note that if you don't play ...c4, Ba3 sometimes fails to ...cxd4 cxd4 Bxa3 Nxa3 Qa5+ picking up the knight, but if you play ...c4 white doesn't have to think about that possibility.
   [title "4.Ba3"]
   [fen "rn2kb1r/pp2pppp/1q3n2/2pp4/3P1P2/2PQPN2/PP4PP/RNB1K2R b - - 0 1"]
  
   1...c4 2.Qc2 Qc6 3.b3 b5 4.Ba3
  
  Similarly, your "good" bishop is already good. But it doesn't gain much from ...c4.
  You have a good square on e4, but if you put a knight there then white will exchange it for his and there will be a pawn on that square. If white plays Ne5 and you exchange it, they can take fxe5 and get an attack over the f-file.
  You removed the tension (white doesn't have to care about the option ...cxd4 anymore) and now have few good pawn breaks (I don't think ...f6 and ...e5 is going to work soon). If one the other hand white manages e3-e4, then your pawn on c4 may become weak. Or white can attack it with b3 and a4. Or go for a kingside attack with g2-g4.
  So I don't see your points. That said, 0.7 is more of an advantage than I had expected, maybe there is a way for them to force you to waste some more time, or win a pawn?
  
  
  ---
  
  ### Answer by username_4 on 2019-02-07. Score: 7
  
  The other answers were great, but I think you could sum it up like this :
  the player who has built the stonewall is looking for a locked center so that he can benefit from the time to build up an attack on your king, funneling his pieces over in the vicinity of your king without having to worry about central counter-play.
  
  Doing c4 might superficially look like gaining space, but it really helps the opponent in keeping the center locked, by giving up a possible break which might be needed.
  
  
  ---
  
  ### Answer by username_5 on 2019-02-07. Score: 5
  
  ...c4 is generally bad because it releases the tension on White's d4-pawn. This makes it much easier for White to get away with pushing e4, since the e3-pawn doesn't need to support the d4-pawn anymore.
  
  You're correct that White does have a weak hole on e4, but after playing Qc2 and Nbd2, he's ready to push e4 and gain a central initiative.
  
  
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  ### Answer by username_6 on 2019-12-22. Score: 1
  
  It is slow. At a time you should be developing and getting the rest of your pieces out, you play c4, meaning that eventually to get your standard play with b5-b4, you will need to finish your development, then move your queen again, and only then get in b5-b4. That gives time for white to do a lot of different things, depending on how you develop. You will also have to take the time to play Ne4 almost immediately so you can play f5 since if white gets in e4 first, that is also going to be super advantageous to him.
  
  It is a common mistake to change the base of the pawn structure in the opening, slowing one's play.
  
  
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