Difference between revisions of "Opposition"

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'''[[Main Page|Home]] * [[Chess]] * [[Pieces]] * [[King]] * Opposition'''
 
'''[[Main Page|Home]] * [[Chess]] * [[Pieces]] * [[King]] * Opposition'''
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[[FILE:Hilma af Klint - Group IX SUW, The Swan No. 1 (13947).jpg|border|right|thumb| [[:Category:Hilma af Klint|Hilma af Klint]] - Group IX SUW, The Swan No. 1
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| rowspan="2" | '''Opposition''',<br/>a relational geometrical property of both king [[Origin Square|origins]]. The '''direct''' opposition, with the closest possible [[Manhattan-Distance|Manhattan-distance]] of two, implies both kings face each other on a [[Ranks|rank]] or [[Files|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 [[General Setwise Operations#Intersection|intersection]] of all ranks and files with an even [[Ranks#RankDistance|rank-]] or [[Files#FileDistance|file-distance]] (including exclusive zero).
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<ref>[[:Category:Hilma af Klint|Hilma af Klint]] - [https://commons.wikimedia.org/wiki/File:Hilma_af_Klint_-_Group_IX_SUW,_The_Swan_No._1_(13947).jpg Group IX SUW, The Swan No. 1], 1915, [https://en.wikipedia.org/wiki/Wikimedia_Commons Wikimedia Commons]</ref> ]]
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'''Opposition''',<br/>a relational geometrical property of both king [[Origin Square|origins]]. The '''direct''' opposition, with the closest possible [[Manhattan-Distance|Manhattan-distance]] of two, implies both kings face each other on a [[Ranks|rank]] or [[Files|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 [[General Setwise Operations#Intersection|intersection]] of all ranks and files with an even [[Ranks#RankDistance|rank-]] or [[Files#FileDistance|file-distance]] (including exclusive zero).
  
 
In late [[Endgame|endgames]], specially [[Pawn Endgame|pawn endgames]], where kings may obligated to move, gaining (winning) the direct opposition is often a decisive [[Tactics|tactical]] feature, when it puts the defending [[Side to move|side]] in [[Zugzwang|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|triangulation]] with its king to gain opposition, or in a more general sense to consider [[Corresponding Squares|corresponding squares]].  
 
In late [[Endgame|endgames]], specially [[Pawn Endgame|pawn endgames]], where kings may obligated to move, gaining (winning) the direct opposition is often a decisive [[Tactics|tactical]] feature, when it puts the defending [[Side to move|side]] in [[Zugzwang|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|triangulation]] with its king to gain opposition, or in a more general sense to consider [[Corresponding Squares|corresponding squares]].  
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|  Oppositions <ref>[http://www.schachfieber.de/2009/12/31/kampf-der-koenige-aufklaerung-ueber-opposition/ Kampf der Könige: Aufklärung über "Opposition"] (German)</ref>
 
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=See also=  
 
=See also=  
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[[Category:Hilma af Klint]]
 
[[Category:The Urge]]
 
[[Category:The Urge]]

Latest revision as of 16:10, 6 March 2020

Home * Chess * Pieces * King * Opposition

Hilma af Klint - Group IX SUW, The Swan No. 1 [1]


Opposition,
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.

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

  1. ↑ Hilma af Klint - Group IX SUW, The Swan No. 1, 1915, Wikimedia Commons

Up one Level

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