Interference

cg:interference@1Verified by Lector64 v3.3.0-beta.2 · 2d7b7216 · 2026-09-23

A piece is placed on the empty segment of an enemy slider's defensive line and cuts the defender off from the enemy piece it was guarding.

Cite this entry
ChessGrammar (2026). Interference. In: ChessGrammar: A reference for chess concepts, Tactics grammar, edition v3.0. Entry cg:interference@1. https://chessgrammar.com/motifs/tactics/interference
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Bishop line interference

Start position

Predicateall must hold

P1Before the move, an enemy slider defends another enemy piece along a rank, file, or diagonal, with nothing standing between them.
P2The move places a piece on that empty stretch, between the two enemy pieces.
P3After the move, the defending slider no longer reaches the piece it was guarding, so the guard is cut.
P4The cut wins material. Under every best defence, capturing the now undefended piece wins more than restoring the guard would concede. A real threat must exist from the start. When the guarded piece is the king, the cut counts only if it leads to checkmate, because a king is never captured.

Identity

the definition and its boundary

4 predicates

Type position

Be5

The bishop moves from b2 to e5, onto the e-file between the white queen on e6 and the bishop on e4 that she was defending. The guard is cut. White can reply with Rd5, but the bishop on e4 is still lost, and Qxe4+ takes it with check.

5r1k/6pp/3RQ3/1p3P2/4Bq2/7P/1b3PK1/8 b - - 0 40

Boundary

Be5

Interference and Pin differ in whose line is occupied. In Interference, a piece enters an enemy defensive line. A pin constrains an enemy piece on the attacker's line. Blocking an enemy line of attack is only a parry. In the counter-example shown here, the defending queen is absent, so there is no defensive line to cut and no Interference.

The queen on e6 is gone. The bishop still moves to e5, but no guard on the e-file remains to be cut. No line connects an enemy piece to the bishop on e4, so there is no interference.

5r1k/6pp/3R4/1p3P2/4Bq2/7P/1b3PK1/8 b - - 0 40

Structure

the variants

6 variants · 4 axes

4 axes

The forms below are grouped by the feature they describe. A feature may have no separate named form. Open a form to read its criteria and see its examples.

How many enemy guards the posed piece severs· 0

No separate named form is published for this axis.

The shared nature of the two severed guards, when cut=double· 2

Novotnydouble-interference sacrifice

The two cut guards are of different natures.

6 ex.

Plachuttalike-line interference

The two cut guards share the same nature.

7 ex.

Which piece owns the defensive line the posed piece severs· 3

Rook-Line Interference

The severed guard is a rook.

8 ex.

Bishop-Line Interference

The severed guard is a bishop.

5 ex.

Queen-Line Interference

The severed guard is the queen.

4 ex.

The identity of the piece WE pose on the enemy's guard line· 1

Pawn Interference

The interposing piece is a pawn of the attacking side.

7 ex.

Named in the literature, not in the taxonomy· 4

forms the literature names but the taxonomy does not carry as entries of their own

Grimshawmutual interference

Outlined — no formal discriminator published.

outlined

Würzburg-Plachutta

Outlined — no formal discriminator published.

outlined

Holzhausensame-line interference

Outlined — no formal discriminator published.

outlined

Focal Interferencefocal-point interference

Outlined — no formal discriminator published.

outlined

Examples

the corpus

34 examples

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Interference

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Identity

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Structure

Examples

Interference

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Identity

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Structure

Examples