Selfmate - a chess problem where White forces mate
Selfmate
Definition
A selfmate is a genre of chess composition in which White, moving first, is obliged to force Black to deliver checkmate to White’s own king within a stipulated number of moves, against Black’s will and with perfect play from both sides. Unlike an ordinary game, where a player seeks to avoid being mated, in a selfmate White cooperates with (or compels) Black to give the final mating blow. Black, for its part, tries to resist mating White and to prolong the struggle as long as possible.
Nomenclature & Related Forms
- s#n — the conventional abbreviation in problem notation, meaning “selfmate in n moves.” For example, s#3 denotes a selfmate in three moves.
- Reflexmate (r#) — a closely-related genre in which both sides are obliged to give mate if they can; it can be viewed as a selfmate with an additional reflex condition.
- Helpmate (h#) — a cooperative composition in which Black assists White in mating Black’s king; conceptually the “mirror image” of the selfmate.
How It Is Used in Chess
Selfmates are rarely, if ever, encountered in over-the-board tournament play; their natural habitat is the world of chess problems and studies. Composers use the genre to explore paradoxical ideas, intricate move orders, and striking tactical themes that cannot arise in competitive games.
In problem-solving competitions, a correct solution to a selfmate involves:
- Announcing the set play (the logical threats that exist before the first move, if any).
- Finding the key move (White’s first move) that initiates the forced sequence.
- Demonstrating every Black defence and showing how White still compels Black to give mate on schedule.
Strategic & Historical Significance
The selfmate originated in the mid-19th century as problemists began to explore “inverse” forms of the game. Notable pioneers include Samuel Loyd (U.S.), Ottó Titusz Bláthy (Hungary), and the Bohemian school of composers.
Several strategic themes have become classics within the genre:
- Suicide sacrifices that remove key defensive pieces so Black is forced to checkmate.
- Annihilation of flight squares, driving White’s king into a mating net.
- Counter-obligations, where White uses zugzwang or tempo moves so that any Black reply must give mate.
Illustrative Example: Loyd’s “Excelsior” Selfmate in 2
One of the most famous miniatures is Samuel Loyd’s 1858 selfmate (often nicknamed “Excelsior” in homage to another Loyd masterpiece).
[[Pgn| [FEN "2b5/2Q5/8/2N5/2n5/8/5K2/4B3 w - - 0 1"] 1. Qf7!! Nd6 2. Be7 s# |fen|2b5/2Q5/8/2N5/2n5/8/5K2/4B3 w - - 0 1]]Explanation:
- 1.Qf7!! — the key. White positions the queen so that any knight move will interfere with Black’s control of f7 while simultaneously blocking escape squares for the White king on f2.
- Black has only one serious try, 1…Nd6, removing the guard of e4.
- 2.Be7 forces Black to give mate: 2… Nxf7# is unavoidable because the knight is pinned against its own king, and any alternative move allows immediate mate by White or violates the stipulation.
A Modern Selfmate in 3 (s#3) by Michel Caillaud, 1998
[[Pgn| [FEN "8/1K6/3PR3/3n4/8/1B6/8/8 w - - 0 1"] 1. Bc4 Nb4 2. Re8 Nc6 3. Re1 Nd8 s# |fen|8/1K6/3PR3/3n4/8/1B6/8/8 w - - 0 1]]Highlights:
- White drives Black’s knight into increasingly restricted squares.
- After the final move 3…Nd8#, Black is compelled to mate because all alternative knight moves are blocked and any king move would be illegal.
Interesting Facts & Anecdotes
- The longest published selfmate is an s#203 by Thomas R. Dawson (1931), demonstrating near-endless depth.
- World champion Mikhail Tal reportedly enjoyed solving selfmates, claiming they “teach you how the pieces feel about each other.”
- In 1914, a selfmate problem was included in The Times of London’s Christmas puzzle section, drawing thousands of solutions sent by post.
- Computer engines, while tactically powerful, often struggle with selfmates because their evaluation functions resist positions in which the side to move steers into mate voluntarily.
Key Takeaways
Selfmates invert normal chess logic, demanding creative, paradoxical play. Though irrelevant to practical over-the-board strategy, they enrich the art of chess composition and provide a rigorous mental workout for solvers who must think “against the grain.”