Answers.Body: <p>We can't read the engine's mind.  The evaluation is the result of calculation to depth 22, i.e. looking 11 moves ahead; the main line(s) after both 1 Bxe4 and White's alternatives should give some idea of why the engine gives White +0.6 here and why the alternatives (mainly Bg4 and Bh3) are worse.</p>
  <p>Looking at it without an engine, we might guess that after the trades on e4 White has a worse Bishop but more space and a Queenside majority -- and no more worries about a Black attack on the Kingside.  After 1 Bxe4 Qxe4 2 Qxe4 dxe4 White can move the Bishop outside the pawn chain with tempo (discovered attack on bPe4), and 3 Bg5 also controls d8 so that after Black defends the pawn White can continue 4 Rd1 and 5 d5, curing the d5-hole (White doesn't want to see Black play Rd5 or Kd5), start getting the Queenside pawns moving, and maybe use the d-file.  White also has the option of not trading Queens and instead trying to use the e-file with something like Qd1 (Black won't play Re8 because then Bd2 wins).</p>
  <p>If Black answers 1 Bxe4 with dxe4 then White seems to win the e-pawn by moving the Bishop (2 . . . f5 doesn't help Black because 3 f3 and the pinned pawn falls); then the &quot;+0.6&quot; might mean that Black has some compensation thanks to the better Bishop.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-08-17T02:09:23.467Z
Answers.Text: "We can't read the engine's mind" - in some cases I'd agree, but more often than not it's possible to understand why the engine likes one move over another. It just takes a bit of digging and analysis.
Answers.UserDisplayName: Inertial Ignorance
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-08-17T02:54:49.600Z
Answers.Text: Well if you have Stockfish then sometimes it "just takes a bit of
  digging and analysis" to get some sense of its reasoning by
  having it show you its main lines and ask about alternatives that 
  seem promising.  Without an engine, most of us can't confidently analyze
  a position like this out to depth 22.
Answers.UserDisplayName: Noam D. Elkies
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-08-17T05:08:20.867Z
Answers.Text: No that's what I meant, digging with an engine to help you understand said engine. A person trying to understand Stockfish's moves on their own is often gonna have a bad time.
Answers.UserDisplayName: Inertial Ignorance
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-08-17T01:55:20.673Z
Answers.LastActivityDate: 2022-08-17T01:55:20.673Z
Answers.UserDisplayName: Noam D. Elkies
Body: <p><a href="https://lichess.org/analysis/r3q1k1/ppb2p1p/2p3p1/2Pp1B2/1P1Pn3/4B3/P1Q2PPP/4R1K1_w_-_-_0_1?color=white#0" rel="noreferrer">Stockfish</a> evaluates this as advantageous for White (+0.6 at depth 22), with Bxe4 being the only move retaining the advantage.
  Why is this so good for White?</p>
  <ol>
  <li>We give up the bishop pair</li>
  <li>We're left with the bad bishop vs the opponent's good bishop</li>
  </ol>
  <p>Even after 1. Bxe4 Qxe4 2. Qxe4 dxe4 which looks like a textbook good bishop vs bad bishop scenario, Stockfish thinks that White is better (+0.2).
  Why is Bxe4 the best move and why does it lead to an advantage for White?</p>
  <pre><code>    [FEN &quot;r3q1k1/ppb2p1p/2p3p1/2Pp1B2/1P1Pn3/4B3/P1Q2PPP/4R1K1 w - - 0 1&quot;]
  </code></pre>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-08-20T21:03:21.387Z
Comments.Text: Technically, The dark-squared Bishop for White isn't "bad," it's only slightly worse. And the exchange of queens lessens that. Taking your line further with Bh6, for example, with the intention of playing against the loose pawn with f3 highlights how much stronger that bishop can become.
Comments.UserDisplayName: Arlen
Tags: <strategy><pieces><trading><minor-pieces>
Title: Why should White give up the bishop (pair) in this example?
ThreadText: # Why should White give up the bishop (pair) in this example?
  
  (Asked by: username_0 on 2022-08-16)
  
  Stockfish evaluates this as advantageous for White (+0.6 at depth 22), with Bxe4 being the only move retaining the advantage.
  Why is this so good for White?
  
  We give up the bishop pair
  We're left with the bad bishop vs the opponent's good bishop
  
  Even after 1. Bxe4 Qxe4 2. Qxe4 dxe4 which looks like a textbook good bishop vs bad bishop scenario, Stockfish thinks that White is better (+0.2).
  Why is Bxe4 the best move and why does it lead to an advantage for White?
      [FEN "r3q1k1/ppb2p1p/2p3p1/2Pp1B2/1P1Pn3/4B3/P1Q2PPP/4R1K1 w - - 0 1"]
  
  **Tags:** strategy, pieces, trading, minor-pieces
  
  > **Comments:**
  > **username_1**: Technically, The dark-squared Bishop for White isn't "bad," it's only slightly worse. And the exchange of queens lessens that. Taking your line further with Bh6, for example, with the intention of playing against the loose pawn with f3 highlights how much stronger that bishop can become.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_2 on 2022-08-17. Score: 2
  
  We can't read the engine's mind. The evaluation is the result of calculation to depth 22, i.e. looking 11 moves ahead; the main line(s) after both 1 Bxe4 and White's alternatives should give some idea of why the engine gives White +0.6 here and why the alternatives (mainly Bg4 and Bh3) are worse.
  
  Looking at it without an engine, we might guess that after the trades on e4 White has a worse Bishop but more space and a Queenside majority -- and no more worries about a Black attack on the Kingside. After 1 Bxe4 Qxe4 2 Qxe4 dxe4 White can move the Bishop outside the pawn chain with tempo (discovered attack on bPe4), and 3 Bg5 also controls d8 so that after Black defends the pawn White can continue 4 Rd1 and 5 d5, curing the d5-hole (White doesn't want to see Black play Rd5 or Kd5), start getting the Queenside pawns moving, and maybe use the d-file. White also has the option of not trading Queens and instead trying to use the e-file with something like Qd1 (Black won't play Re8 because then Bd2 wins).
  
  If Black answers 1 Bxe4 with dxe4 then White seems to win the e-pawn by moving the Bishop (2 . . . f5 doesn't help Black because 3 f3 and the pinned pawn falls); then the "+0.6" might mean that Black has some compensation thanks to the better Bishop.
  
  > **Comments:**
  > **username_3**: "We can't read the engine's mind" - in some cases I'd agree, but more often than not it's possible to understand why the engine likes one move over another. It just takes a bit of digging and analysis.  
  > **username_2**: Well if you have Stockfish then sometimes it "just takes a bit of digging and analysis" to get some sense of its reasoning by having it show you its main lines and ask about alternatives that  seem promising.  Without an engine, most of us can't confidently analyze a position like this out to depth 22.  
  > **username_3**: No that's what I meant, digging with an engine to help you understand said engine. A person trying to understand Stockfish's moves on their own is often gonna have a bad time.  
  
  ---
  
  