Diag. 30
White Pawns on the King’s side. He will attempt this either by P- KB3 attacking White’s centre or by P-KB4 preventing White from playing P-B5. In the latter case White can only make a breach in the Black barrier by playing P-KKt4 as well. These manœuvres result in the pawn formations given in Diagrams 31 and 32.
Diag. 31
We must now turn to the development of the pieces corresponding to these pawn skeletons. If White plays P-K5
Diag. 32
on his third move, he prevents the Black KKt from reaching KB3, whence he might have moved to Q2. This is a desirable position, from which he could support the advance of P-QB4. But the Knight has other chances of development, to KR3 and B4, whence he can take his share in the attack on the White Pawn at Q4. In consequence White must postpone P-KB4 in order not to intercept the action of the QB on R6. Now, in that case White’s Pawn at his K5 has not sufficient support against the attack by Black’s P-KB3 (Diagram 31), and the latter move gives Black the advantage. The two main variations illustrative of these considerations are:
I
3. P-K5 P-QB4 4. P-QB3 Kt-QB3 5. P-KB4 PxP 6. PxP Q-Kt3 7. Kt-KB3 Kt-R3