Answers.Body: <blockquote>
  <p>why exchanging the knight f3 is a blunder?</p>
  </blockquote>
  <p>It obviously isn't a blunder.</p>
  <p>I suspect you've made the mistake of thinking that if the website tells you that it evaluates Nxf3 as fractionally lower than Nxg2 then that means that Nxf3 is a blunder. It isn't. A blunder is when your large positive advantage turns negative. A blunder loses you the game from a roughly equal position or throws away a winning advantage. It is not when the evaluation changes slightly against you.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-01-15T13:11:48.143Z
Answers.LastActivityDate: 2022-01-15T13:11:48.143Z
Answers.UserDisplayName: Brian Towers
Body: <p>Black (me) to move.</p>
  <p>I took the knight at f3 with my knight at e1. However, Lichess analysis shows that this move is a blunder, and suggests to take the bishop at g2 instead.</p>
  <p>IMO, I am winning no matter I exchange the knight or bishop, but I feel hard to understand why exchanging the knight f3 is a blunder?</p>
  <pre><code>[FEN &quot;r1bq1rk1/pp3ppp/4p3/2Pp4/2P5/P1B2NP1/3NPPBP/R3nRK1 b - - 0 1&quot;]
  
  1...Nxf3? (1...Nxg2!)
  </code></pre>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-01-15T13:07:26.860Z
Comments.Text: A link to the lichess game might be useful. That said 1) I wouldn't worry too much, the difference in the captures is between very, very winning and very, very, *very* winning 2) That said I would have taken the bishop without thinking too hard - bishops are usually a little stronger than knights, especially when you possess the bishop pair, and given the choice I would always take the bishop unless there is a good reason to do otherwise, and here the white squared bishop is potentially about White's best piece.
Comments.UserDisplayName: Ian Bush
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-01-15T21:33:30.623Z
Comments.Text: Did Lichess *actually say* "**blunder**" or is that your interpretation?
Comments.UserDisplayName: user21820
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-01-16T20:32:27.197Z
Comments.Text: @user21820 This is a blunder considered by Lichess. Please see the link: https://lichess.org/GoIUYiwE/black#28.
Comments.UserDisplayName: null
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-01-17T13:14:08.983Z
Comments.Text: Thank you for the link; it seems that the Lichess SF engine used in [that analysis](https://lichess.org/GoIUYiwE/black#28) had searched to a depth where it saw a way to reach much clearer winning position for `Nxg2` than for `Nxf3`, and this yielded −6.7 instead of −3.2, which was significant enough that made it classify it as a blunder. From the engine's viewpoint, −6.7 is very much better than −3.2; although it will almost always win as Black given either, the likelihood that it will fail is much lower for −6.7 than −3.2.
Comments.UserDisplayName: user21820
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-01-17T13:25:17.413Z
Comments.Text: It's a matter of opinion whether you should consider it a blunder or not, because the bishop is really somewhat annoying. To understand the difference, simply try playing against maximum-level SF after `Nxf3` (via Menu > Continue from here), and I would be interested to see the game that you end up with.
Comments.UserDisplayName: user21820
Tags: <analysis><problems><evaluation><blunder>
Title: Analyse a blunder
ThreadText: # Analyse a blunder
  
  (Asked by: username_0 on 2022-01-15)
  
  Black (me) to move.
  
  I took the knight at f3 with my knight at e1. However, Lichess analysis shows that this move is a blunder, and suggests to take the bishop at g2 instead.
  
  IMO, I am winning no matter I exchange the knight or bishop, but I feel hard to understand why exchanging the knight f3 is a blunder?
  
  ```
  [FEN "r1bq1rk1/pp3ppp/4p3/2Pp4/2P5/P1B2NP1/3NPPBP/R3nRK1 b - - 0 1"]
  
  1...Nxf3? (1...Nxg2!)
  
  ```
  
  **Tags:** analysis, problems, evaluation, blunder
  
  > **Comments:**
  > **username_1**: A link to the lichess game might be useful. That said 1) I wouldn't worry too much, the difference in the captures is between very, very winning and very, very, *very* winning 2) That said I would have taken the bishop without thinking too hard - bishops are usually a little stronger than knights, especially when you possess the bishop pair, and given the choice I would always take the bishop unless there is a good reason to do otherwise, and here the white squared bishop is potentially about White's best piece.  
  > **username_2**: Did Lichess *actually say* "**blunder**" or is that your interpretation?  
  > **username_0**: @username_2 This is a blunder considered by Lichess. Please see the link: https://lichess.org/GoIUYiwE/black#28.  
  > **username_2**: Thank you for the link; it seems that the Lichess SF engine used in [that analysis](https://lichess.org/GoIUYiwE/black#28) had searched to a depth where it saw a way to reach much clearer winning position for `Nxg2` than for `Nxf3`, and this yielded −6.7 instead of −3.2, which was significant enough that made it classify it as a blunder. From the engine's viewpoint, −6.7 is very much better than −3.2; although it will almost always win as Black given either, the likelihood that it will fail is much lower for −6.7 than −3.2.  
  > **username_2**: It's a matter of opinion whether you should consider it a blunder or not, because the bishop is really somewhat annoying. To understand the difference, simply try playing against maximum-level SF after `Nxf3` (via Menu > Continue from here), and I would be interested to see the game that you end up with.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_3 on 2022-01-15. Score: 5 | Accepted answer
  
  > why exchanging the knight f3 is a blunder?
  
  It obviously isn't a blunder.
  
  I suspect you've made the mistake of thinking that if the website tells you that it evaluates Nxf3 as fractionally lower than Nxg2 then that means that Nxf3 is a blunder. It isn't. A blunder is when your large positive advantage turns negative. A blunder loses you the game from a roughly equal position or throws away a winning advantage. It is not when the evaluation changes slightly against you.
  
  
  ---
  
  