Except the French defence and the Caro-Kann, there is no game in which an irregular reply to White’s 1.  P-K4 necessitates any special considerations either in development of pieces or pawn formation.  In all such cases it is sufficient to maintain the pawn centre and to occupy such squares with the pieces, whence they cannot be driven away with the loss of a move.  Just one example:  If Black plays 1. ...  P-QB4 (Sicilian defence), White will not play his King’s Bishop to B4, because Black can reply P-K3, and gain a move by P-Q4.

B. Let us now consider the openings in which the first move is 1.  P-Q4 on either side.  Here the centre cannot be cleared as early as in the openings beginning with 1.  P-K4, P-K4.  The advance of a second centre pawn, which there led to a clearance, is not feasible in this case.  White does not command his K4, and for some time to come he will be unable to advance the K pawn beyond K3.  In consequence the K file does not seem a likely opening for the Rooks, and another file must be found for them.  The conclusions arrived at for Black in the French defence hold good for both sides in the opening now under consideration, and accordingly the QB file is that most advantageous for the Rooks.  The advance of the QBP strikes at the opposing centre, and, that being of paramount importance, the Queen’s Knight must not be developed at B3 before the QBP has been pushed on.  Another development might be conceivable for the Rooks; viz. on the KB file, and also the KKt or KR file; here, as we shall see, an occasion may arise for storming the opposing King’s side by a pawn attack.  But in this case, too, although it seems unnecessary to play the QBP, it is advisable to develop the Knight via Q2, as there is a constant threat of the QB file being forced open subsequently by the opposing forces.

We will start with the games in which the QB Pawns are played in the earliest stages of the opening, so that the pawn skeleton in Diagram 35 forms the basis of development.  The sequence of moves is of moment, because the advance of the KP, whether forced or not, determines the possibility of bringing out the Q Bishops.  The simplest process of development based on Diagram 35 is the following, in which both sides block up the QB.

---------------------------------------
8 | #R | #Kt| #B | #Q | #K | #B | #Kt| #R |
|---------------------------------------|
7 | #P | #P |    |    |    | #P | #P | #P |
|---------------------------------------|
6 |    |    |    |    | #P |    |    |    |
|---------------------------------------|
5 |    |    | #P | #P |    |    |    |    |
|---------------------------------------|
4 |    |    | ^P | ^P |    |    |    |    |
|---------------------------------------|
3 |    |    |    |    | ^P |    |    |    |
|---------------------------------------|
2 | ^P | ^P |    |    |    | ^P | ^P | ^P |
|---------------------------------------|
1 | ^R | ^Kt| ^B | ^Q | ^K | ^B | ^Kt| ^R |
---------------------------------------
A    B    C    D    E    F    G    H

Diag. 35