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An Introduction To
by Arthur E. Holmer
One of the most fundamental rules in chess is very simple to state; the king may not move onto (or through) a square that is attacked by an opposing piece. We generally learn this rule in the form of “a king cannot put itself in check”. This rule leads to a king having to do something when placed in check and of course it is checkmate if the attack cannot be blocked.
This rule quietly adds another very interesting dimension to chess play when the two opposing kings approach each other in that they can never occupy adjacent squares. There must always be a square between them. The last king move to a square adjacent to the other king would put the approaching king in check and this is not allowed. So far this seems pretty simple. However, this need for a square between the kings leads to a special position known as "the opposition."
Grandmaster Lev Alburt describes the opposition very well in Chess for the Gifted and Busy1 “Opposition is a special situation occurring when two kings face each other, often on a file, but rarely on a rank or diagonal, with only one square between them. In such a situation, the player not having the move is said “to have the opposition”. Opposition is often used to put an opponent into zugzwang (forcing an undesirable move). Opposition is a very effective tool to fight for the control of a key square”.
Grandmaster Karsten Mueller gives us further information and a rule as he describes the opposition in
Fundamental Chess Endings2. “If we speak of opposition, most often this form is meant.”
|Normal (vertical) opposition. Key squares are d6, e6 and f6.|
|The side (or horizontal) opposition. Key squares are e5, e6 and e7.|
Maneuvers involving the opposition are also described in terms of taking the opposition or losing the opposition. So lets see how the opposition works and how these special terms look during a classic example.
|White to move.|
1. Kd5 ...
White takes the opposition. Note that with completion of this move, White is no longer on the move and is considered to have gained the opposition. This puts Black into zugzwang, that is, having to make a move that favors White. After Black moves his king, White will control (be able to move his King to) at least one of the key squares c6, d6 and e6.
1. … Ke7
This allows the White king to advance.
2. Kc6 ...
White now controls d7.
2. … Kd8
To get in front of the pawn.
3. Kd6 ...
Again taking the opposition, controlling c7, d7, e7 and putting Black into zugzwang.
3. … Ke8
Black must move.
4. Kc7 ...
Black has no way to stop the pawn. If 4. … Ke7, taking the side opposition, then 5. d5 and Black, having to move, will be forced to
lose the opposition. The pawn will queen.
Now, let’s see how the opposition works and how these special terms look during some actual games. The following game is an excellent example of the normal (direct) opposition.
Fullen, Peter J.— Williams, Rufus H., 2018 CCLA Summer Server Series, Section S81319, ECO "B30m"
1. e4 c5 2. Nf3 Nc6 3. Bb5 Nf6 4. Nc3 e6 5. d4 a6 6. Bxc6 bxc6 7. O-O Be7 8. Ne5 cxd4 9. Qxd4 O-O 10. h3 Bb7 11. Bg5 d6 12. Qb4 Qc8 13. Ng4 Qc7 14. Nxf6+ Bxf6 15. Bxf6 gxf6 16. Ne2 Kh8 17. e5 fxe5 18. Qh4 f6 19. Ng3 Qd8 20. Rae1 c5 21. f4 Rg8 22. Ne4 Rf8 23. Re3 exf4 24. Qxf4 Bxe4 25. Qxe4 e5 26. Qh4 Qe7 27. Rg3 Rf7 28. Rg6 Raf8 29. Rf5 e4 30. Kf2 e3+ 31. Ke2 Rg8 32. Rxg8+ Kxg8 33. Qg3+ Rg7 34. Qxe3 Rxg2+ 35. Rf2 Rxf2+ 36. Kxf2 Qxe3+ 37. Kxe3 Kf7 38. c4 Ke7 39. Ke4 Ke6 40. Kf4 h6 41. a3 a5 42. h4 h5 43. a4 f5 44. b3 ...
44. ... Kf6 (Black takes the normal opposition.) 45. Kf3 Ke5 46. Ke3 (White takes the opposition, but cannot hold it for long.) 46. ... f4+ 47. Kf3 Kf5 0-1
After 47. ... Kf5, Black takes the opposition again and will advance the pawn as follows: 48. Ke2 Ke4 49. b4 cxb4 50.Kd1 f3 51. Kd2 Kd4 52. Ke1 Ke3 53. c5 dxc5 54. Kd1 f2 55. Kc2 f1=Q 56. Kb2 Kd3 57. Ka2 Qc1 58. Kb3 Qb1# (Stockfish).
The following game is an excellent example of the side (horizontal) opposition.
Vergara, Rene — Taylor, Ronald D., 2018 CCLA Summer Server Series, Section S81319, ECO "B05l"
1. e4 Nf6 2. e5 Nd5 3. d4 d6 4. Nf3 Bg4 5. Be2 e6 6. O-O Nc6 7. c4 Nb6 8. Nc3 Be7 9. Be3 dxe5 10. dxe5 Bxf3 11. Bxf3 Nxe5 12. Bxb7 Rb8 13. Be4 Nexc4 14. Bxb6 Nxb6 15. Bc6+ Nd7 16. b3 Bf6 17. Rc1 Rb6 18. Ne4 Ke7 19. Nxf6 Nxf6 20. Bf3 Rd6 21. Qc2 Nd5 22. Bxd5 Rxd5 23. Rfd1 Rxd1+ 24. Rxd1 Qc8 25. h3 Rd8 26. Qc5+ Ke8 27. Rxd8+ Qxd8 28. Qxa7 Qd1+ 29. Kh2 Qd6+ 30. g3 f5 31. a4 Qb6 32. Qa8+ Kd7 33. Qf3 Qb4 34. Qd3+ Ke7 35. Qc4 Qxc4 36. bxc4 Kd8 37. f4 c5 38. Kg2 Kc7 39. Kf3 Kb6 40. g4 Ka5 41. gxf5 exf5 42. Kg3 Kxa4 43. Kh4 Kb4 44. Kg5 Kxc4 45. Kxf5 ...
45. ... Kd5 (Black takes the side opposition.) 46. h4 c4 0-1
White is unable to move towards the c-pawn due the f4 pawn. But even if the f4 pawn was not there, Black will maintain the side opposition and keep the
White king from approaching the c-pawn.
Finally, where the following game ends offers an excellent exercise position in the use of the opposition.
Lines, Daniel — Acosta, Errol, 2018 CCLA Summer Server Series, Section S81309, ECO "C01r"
1. d4 e6 2. e4 d5 3. exd5 exd5 4. Nc3 c6 5. Nf3 Nf6 6. Bg5 Be7 7. Be2 O-O 8. O-O h6 9. Bh4 Ne4 10. Bxe7 Qxe7 11. Nxe4 dxe4 12. Nd2 f5 13. c3 Be6 14. Bc4 Nd7 15. Bxe6+ Qxe6 16. Re1 Qf7 17. f3 exf3 18. Qxf3 g6 19. Nf1 Nf6 20. b4 Rae8 21. Rxe8 Rxe8 22. Nd2 Qd5 23. Qxd5+ Nxd5 24. c4 Nxb4 25. a3 Nd3 26. Kf1 Kf7 27. Nf3 b6 28. Ne1 Nxe1 29. Rxe1 Rxe1+ 30. Kxe1 Kf6 31. a4 a5 32. Kd2 Kg5 33. Ke3 h5 34. Kf3 h4 35. h3 f4 36. Ke4 Kf6 37. Kxf4 g5+ 38. Ke4 1/2-1/2.
A suggested solution line is 38. ... Ke6 39. d5+ Kd6 40. Kd4 cxd5 41. cxd5 Ke7 42. Ke5 Kf7 43. d6 b5 44. axb5 a4 45. b6 a3 46. d7 a2 47. d8=Q a1=Q+ 48. Qd4 Qc1 49. Qd7+ and mate in 14 (Stockfish.)
1) Alburt, Lev and Lawrence, Al, Chess for the Gifted and Busy, second revised edition, W.W. Norton, New York, 2015, p. 173.
2) Mueller, Karsten and Lamprecht, Frank, Fundamental Chess Endings, Gambit Publications, London, 2001, pp. 23-24.