Breaking Fischer's Hold on Me, When should I do BxN and Give up the 2 Bishops?

Growing up I read that Bobby Fischer loved the 2 Bishops.   And Bobby was my hero!  So if he liked the two bishops, then by golly, so would I!

 

Here's the problem.  I've lost a couple of games that may be traced (I'm not really sure) to my reluctance to give up a bishop for a knight.  I'd pin a knight (either against king or queen) and when the bishop got put to the question by the rook pawn I'd invariably retreat to the "a" or "h" square.   In several games I could have even doubled up the opponent's pawns if I had done BxN.  

 

But Bobby's voice could be heard in the back of my brain:  "Don't give up the two bishops!"

 

So, I need to exorcise Bobby's demon from my game, and I want to ask, "When, or actually what positional or strategic or dynamic elements have to be present for me to exchange off a Bishop for a Knight in a game?"

There are things you should look for in the position that would maybe give you some hints as to whether or not to exchange. If it's a closed position (pawns are locked up in the center), it may be good to take the knight. If the center is clear, then hold on to the bishops. If it's a "bad bishop" (all your pawns are on that bishop's color), take the knight. If the knight is on a strong outpost, take the knight. If you're still early in the game, it may be ok to take the knight; if it's later in the game, you may want to hang onto the bishop. I can't say that I know these things from experience; it's just what I've read. 

 

Thanks John, that's very helpful!

There is no ultimate rule for that. The general rule of thumb is, "Trade your bad pieces for your opponent's good pieces". What makes a piece good or bad is a topic one could write volumes about.

 

In some positions your bishop pair isn't too strong, because either one or both bishops don't do much of anything useful and there is no clear way to put them to work. In others, your bishops might be fine, but, for example, the opponent has a beastly knight, and you simply HAVE to take it out, even by exchanging it for your strong bishop.

 

 

I'll just make up some examples. Here, I would keep the bishop pair:

 

Here, I would give it up:

 

Thanks MayCaesar for the diagrams and tips.  Here's my game where I believe I should have snapped off my opponent's knight with my bishop.  But my reluctance to part with the vaunted and much-touted bishop pair was my undoing:

 

https://www.chess.com/daily/game/166626208

 

[I clicked on the "chess diagram" to insert, spent about 10 minutes trying to figure out where a FEN or PGN was on my game above, but failed, lol.]

 

Anyways, on my 12th or 13th move I think I should have taken my opponent's knight.  But I just didn't want to give up my bishop!  

Everything is relative. Bishops are generally considered better than knights, and having 2 bishops when your opponent doesn't is generally consider to be a moderate advantage, but it all depends on the position. It's hard to teach positional understanding. There are plenty of good books on positional chess out there, but since I can't get too into detail in a single post, I will instead say something basic and vague: don't live so firmly by rules and ideas such as this one. I never even would sacrifice exchanges for positional reasons until I was a 2000 because I always thought that rooks were practically unconditionally better than bishops or knights. You have to break through such simplistic thinking. Good luck.

You are welcome.  I looked at your game, and yes, on the 13th move taking the knight with your bishop would be great, especially due to the tactics: after 13. Bxf6 gxf6 14. Qh6 Nd7 15. Bb5 your opponent would have to give up a lot of material to not get mated.

 

I can also give an example of one of my daily games, which ended with my opponent blundering a piece, sadly, but there are still moments highlighting the bishop pair decisions: