minor pieces

[soheil_hooshdaran]

Hello.
We all know the traditional definition of a good and a bad bishop, but when exactly is a Bishop that can be termed bad traditionally, is considered good? One famous example is Botvinnik-Kan,, Leningrad 1939
3r2k1/5pp1/bp3q1p/2pBpP2/2P5/P3P2P/2Q3P1/5RK1 w - - 0 1
where Botvinnik played 1.e4

[IM Jack Rudd]

White's bishop there is good because it is doing good things. It is attacking the f7 pawn, it is defending the c4 pawn, and it is preventing any invasion by black down the d-file.

There's no particular hard-and-fast rule; the usual test is whether you'd want to exchange the relevant piece off.

[Roger de Coverly]

There's no particular hard-and-fast rule; the usual test is whether you'd want to exchange the relevant piece off.

You could also add whether there's a Knight on the board. Give Kan a Knight and have it buzzing round the White King and Botvinnik's decision to cut off the Bishop with e4 might look suspect.

[Mike Truran]

buzzing round the White King

I don't understand. What does "buzzing round the White King" mean? And what does "cut off the bishop" mean? Does "suspect" mean the same as "dangerous"?