A quiet bishop move is one that does not deliver a check, does not fork, and usually it doesn’t even attack a piece directly. Indeed, it appears to do nothing.
But it does.
The forcefulness of the Quiet Bishop Move can be seen best from the following examples.
New York, 1924
1.Nf3 d5 2.c4 e6 3.g3 Nf6 (The text move is a little passive. Black has several options here including 3…c6, 3…dxc4, and 3…g6.) 4.Bg2 Bd6 5.O-O O-O 6.b3 Re8 7.Bb2 Nbd7 8.d4 c6 9.Nbd2 Ne4 10.Nxe4 dxe4 11.Ne5 f5 12.f3 exf3 13.Bxf3 Qc7 14.Nxd7 Bxd7 15.e4 e5 16.c5 Bf8 17.Qc2 exd4 18.exf5 Rad8 19.Bh5 Re5 20.Bxd4 Rxf5 21.Rxf5 Bxf5 22.Qxf5 Rxd4 23.Rf1! Rd8 24.Bf7+ Kh8
25.Be8! (The bishop does nothing except to isolate the enemy king. But now White has several forced mates. First, he threatens 26.Qxf8#. Black can try 25…Rxe8, but after 26.Qxf8+, White has the well-known back rank mate. And Black is still mated after 25…h6 26.Qxf8+ Kh7 27.Bg6+! Kxg6 28.Qf5#. Black resigns.) 1-0
Zoltan Ribli-Andras Adorjan
1.Nf3 c5 2.c4 Nf6 3.Nc3 b6 4.e3 e6 5.d4 cxd4 6.exd4 Bb7 7.a3 d5! 8.cxd5 Nxd5= 9.Ne5 a6 10.Qa4+ Nd7 11.Nxd5 b5! 12.Qb3 Bxd5 =/+ 13.Qg3 Nxe5 14.dxe5 h5! 15.h4 Rc8 -/+ 16.b4 g6 17.Bg5 Be7 18.Bxe7 Qxe7 19.Be2 Bc4! 20.Rc1 O-O! 21.Bxh5 a5! 22.bxa5 Qa7! 23.Bd1 Qxa5+ 24.Qc3 Qa8! 25.Qe3 Rfd8 26.Bf3? Qa5+ 27.Qc3
27…Bf1!! (The bishop does nothing except to isolate the enemy king. As an added bonus White’s queen is now being attacked by the Rook. Even here the bishop is also quiet, allowing another piece to potentially capture the queen. I’ll let you figure out why White can’t play 28.Qxa5?) 0-1
A bishop move that is a little louder.
Walter Harris-Anthony Cantone
Omaha, Nebraska, July 24 1959
1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 d6 8.c3 O-O 9.h3 Na5 10.Bc2 c5 11.d4 Qc7 12.Nbd2 Nc6 13.dxc5 dxc5 14.Nf1 Rd8 15.Qe2 Be6
(So far this is all theory.
GM Fischer-GM Erich Eliskases, Mar del Plata, Argentina, 1960 continued instead with the alternate 15…Nh5!?. White played the simple, and yet strong, 16.a4 Rb8 17.axb5 axb5 18.g3 g6 19.h4 Be6 20.Ne3 c4 21.Ng5 Bxg5 22.hxg5 Na5 23.Ng4 Bxg4 24.Qxg4 Nb3 25.Bxb3 cxb3 26.Be3 Ra8 27.Rxa8 Rxa8 28.Rd1 Qc6 29.Rd5 f5 30.Qd1 f4 31.gxf4 exf4 32.Qxb3 Qc4 33.Qxc4 bxc4 34.Bd4 f3 35.Be3 h6 36.gxh6 Nf6 37.Rd6 Kf7 38.Rxf6+ Kxf6 39.Bd4+ Kg5 40.h7 Kf4 41.Kh2 g5 42.h8=Q Rxh8+ 43.Bxh8 g4 44.e5 1-0.)
16.Ne3 h6 17.Nh2 Rac8 18.Nf5!? Bxf5 19.exf5 c4 20.Ng4! Re8 21.Qf3 Rcd8 22.Qg3! Kh8 23.Nxh6! gxh6 24.Bxh6 Rg8 25.Qh4 Nh7? 26.f6! Bxf6