Opposition

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Opposition is a relational geometrical property of both king origins. The direct opposition, with the closest possible Manhattan-distance of two, implies both kings face each other on a rank or file. Along a common line, the so called distant or diagonal opposition have a Manhattan-distance of four, while they are particular cases of all virtual oppositions on the otherwise empty board as intersection of all ranks and files with an even rank- or file-distance (including exclusive zero).

In late endgames, specially pawn endgames, where kings may obligated to move, gaining (winning) the direct opposition is often a decisive tactical feature, when it puts the defending side in zugzwang to abandon opposition and to move the king away, and potentially allowing the attacking king a breakthrough to access important squares. Depending on other obstructions, similar is true for distant or diagonal opposition, as intermediate step to gain the direct opposition. Often, in rather blocked pawn endings, the attacking side may apply triangulation with its king to gain opposition, or in a more general sense to consider corresponding squares.

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Oppositions [1]

See also

Publications

  • Reiner Seidel (1992). Das Gesetz der Opposition. Rochade, Vol. 26, No. 6, pp. 19-21. ISSN 0179-3934. (German)

External Links

References

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