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Masuk

Only-move annotation symbol

Also known as: □

The □ square marks a move the annotator considers the only reasonable choice in the position.

This page is temporarily shown in English. Complete localization will be added in a later stage.

Explanation

The □ sign is read as “only move.” It warns that the reasonable alternatives fail, allow a serious loss, or do not meet the position's specific demand. The marked move may be defensive, tactical, or apparently quiet.

In , the text format for games, the original specification distinguishes Numeric Annotation Glyph (NAG) $7, a forced move because all others lose quickly, from $8, a singular move with no reasonable alternatives. Scid vs. PC displays □ for $8, while a printed source may use the square more broadly. Reading the underlying number preserves the distinction.

“Only” does not always mean the only legal move. A king may have several rule-compliant replies, yet only one avoids mate or maintains the balance. The symbol also records the judgment of the available analysis; deeper examination may uncover another defense.

1. □ preserves the defense

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The Black queen threatens Qxh2#.
A concrete threat

Black threatens Qxh2#. Many moves are legal, but the defense must change the protection of without conceding decisive material.

Common confusions

Only legal move

Several moves may be legal under the rules while only one avoids a decisive deterioration.

Excellent move

□ describes necessity, not beauty. An obvious or unpleasant move can be the only one that works.

Sources

  1. 1.System of Signs, Chess Informant / ChessBase
  2. 2.Standard: Portable Game Notation Specification and Implementation Guide, Steven J. Edwards (coordinator)
  3. 3.NAG Values, Scid vs. PC

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