Oct 6, 2011, 3:20 PM |

   White has a K-side pawn majority of two to one.

Capablanca's rule states that you start mobilizing a pawn majority by pushing the unopposed pawn, the one with no enemy pawn ahead of it on the same file. 



This generally eases the creation of a passed pawn.  But that startegy fails here: 1.g6 hxg6  2.hxg6 Kf6  3.Kh5 Kg7, and the pawn is blockaded.

  Or, 1.g6 hxg6  2.h6 Kf6  3.Kh4 Kf7  4.Kg5 Kg8  5.Kxg6 Kh8, with a positional draw.

To win, White defies the rule and pushes the opposed pawn instead, 1.h6.  After 1...Ke6  2.g6 Black cannot stop White from promoting at h8.