Chess Pins: The Difference Between Absolute and Relative

The difference between an absolute and a relative pin decides whether your threat is real. Dawn on when a pinned piece should move anyway — and win.

For a long time I used one word to mean two things and never noticed the seam.

I'd say "I've got him pinned" whether my bishop was holding a knight against a queen or against a king, and I treated both the same way — pile on, win the piece, feel clever. Then I'd lose. The pinned knight would move anyway, right into the fight, and everything I'd built would come apart in a single tempo. I'd stare at the board like the rules had shifted mid-game.

They hadn't. There are two kinds of pin, and the difference between them isn't a detail. It's the whole thing. One kind is enforced by the law of the game. The other is enforced only by your opponent's good sense, and good sense can be a trap.

A pin is when a piece can't move — or shouldn't move — because doing so exposes something more important behind it on the same line. A bishop, rook, or queen does the pinning, because only those three attack along a straight line. The pinned piece sits in front. The valuable thing sits behind.

That much every beginner learns, and every site will tell you. What took me years to feel is that "can't move" and "shouldn't move" are not the same sentence. They live in different rooms of the game.

[[board pgn="1. e4 e5 2. Nf3 Nc6 3. Bb5" caption="The Ruy López. That b5 bishop is pinning nothing yet — but the shape is the one every pin borrows from."]]

When the thing behind the pinned piece is the king, the piece truly cannot move. The law forbids it. When the thing behind is merely valuable — a queen, a rook — the piece can move, and sometimes moving it is the best decision on the board. I was applying the logic of the first case to positions that were the second case, and paying for it.

The Endgame Journal collects our writing on openings, tactics, endgames, and the habits that separate players who improve from players who plateau. Every article is written by people who teach chess, not by a content farm.

Chess Pins: Absolute vs Relative, and Why It Matters | Endgame Society