From Wikipedia, the free encyclopedia.
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Actual play - see post-key play.
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Albino - a problem in which, at some point in the solution, a
white pawn on its starting square makes each of its four possible moves
(forward one square, forward two squares, capture to the left, capture to the
right). If the same behaviour is exhibited by a black pawn, it is a
Pickaninny.
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Allumwandlung - a problem in which the solution includes pawn
promotions to all possible pieces (in orthodox chess, to bishop, knight, rook
and queen; in fairy chess, possibly to
fairy pieces).
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Anticipated - if the theme and setting of a
particular problem has already appeared in an earlier problem without the
knowledge of the later composer, the problem is said to be anticipated.
The position does not have to be exactly the same, just very similar.
Where this is done deliberately by the later composer, the term
plagiarised is more appropriate. There is a real chance of anticipation
if the problem has a realitvely simply theme, since there are only a finite
number of positions and themes, and chess problems have been composed for
hundreds of years. However, anticipations are not always noticed immediately.
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Aristocrat - a problem which has no
pawns in the initial position.
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Babson task - a problem in which black promotion defences to all
possible pieces are answered by white promotions to the same piece black has
promoted to. An extreme form of
Allumwandlung.
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Block - a problem in which the key provides no
threat, but instead puts black in a position of
zugzwang, where every move leads to a mate. In a complete block,
all of black's moves have mates provided in the set play and the key
is simply a waiting move; in an incomplete block, not all black moves
are provided with mates in the set play - the key provides for those that
don't; in a mutate some of the mates provided in the set play are
changed following the key.
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By-play - variations not directly connected to the
problem's theme.
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Clearance - in general, the movement of one piece so that
another can move to a particular square. In square vacation the first
piece moves so that the second can occupy the square on which it stood; in
line vacation the first piece moves so that the second can pass over the
square on which is stood on the way to its destination; line clearance,
also known as the Bristol, is a particular type of line vacation in
which a piece moves along a line so that another piece can move a shorter
distance behind it along the same line.
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Cook - a second key move, unintended by the
composer. A cook is a serious flaw, and invalidates a problem. The publication
of cooked problems was once common, but in the modern era computers can be
used to check for cooks, and cooked problems are rarely published.
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Cylindrical board - a board in which the a and h-files
are considered to be connected (a "vertical cylinder") or the first and eighth
ranks are connected (a "horizonal cylinder"). A combination of the vertical
and horizontal cylinders is called an "anchor ring".
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Directmate - a type of problem where white, moving first,
is required to checkmate black in a specified number of moves against any
defence. Such a problem is usually indicated by the stipulation "mate in two"
(or however many moves is necessary) or "checkmate in two". The term
directmate is useful to distinguish these sorts of problems from
helpmates, selfmates, reflexmates and others.
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Dual - ideally, white should have only one move at each
juncture which solves a problem - if white has an alternative at any stage
other than the first move, this is a dual. A dual is not as serious a
flaw as a cook, and in minor lines, duals may be permissible
(opinions differ on this point). Some problems make a virtue out of dual
avoidance - of two apparently equivalent white moves, only one works.
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Duplex - a type of problem in which there are two
solutions, the second one reversing the roles of the colours in the first. The
most common type is the duplex helpmate, in which the two solutions
to be found are: black moves first and cooperates with white to be mated; and
white moves first and cooperates with black to be mated.
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Economy - economy is generally regarded as a good thing
in chess problem composition, though exactly what is meant by it, and exactly
what it is most important to be economical with, is open to debate. Eceonomy
of material or force (not using more pieces than necessary), economy of space
(using the chessboard to its fullest, not cramming all the pieces into one
corner) and economy of motivation (keeping all lines in the solution relevent
to the theme) are all regarded as important.
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Excelsior - a problem in which a pawn on its starting
square in the initial position moves the length of the board to be promoted
during the course of the solution. Named after one such problem by
Sam Loyd.
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Fairy chess - chess played with non-orthodox rules.
Examples are circe, maximummers, problems with unorthodox
pieces (fairy
pieces) and problems with unorthodox boards (such as cylindrical
boards, or grid boards).
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Flight (square) - a sqaure to which the black king can
legally move (that is, one not guarded by a white piece, and not occupied by a
black piece). If black plays a piece to one of these squares, thus decreasing
the king's mobility, it is a self-block. If he moves a piece from one
of these squares, it is square-vacation.
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Grid-board - a kind of board used in fairy chess
which is divided into a grid of 16 2x2 squares. For a move to be legal, the
moving piece must pass over at least one of these grid-lines.
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Grimshaw - a common device featuring two black pieces mutually
interfering with each other on a single square.
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Heavy - adjective applied to a problem which has a
relatively large number of pieces in the initial position. Heaviness should be
avoided where possible in the interests of economy.
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Helpmate - a type of problem where white and black cooperate to
put black in mate within a specified number of moves. Unless otherwise
specified, black moves first in helpmates. See also duplex.
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Interference - the closure of the line of one piece by a
second piece, thus limiting its movement and cutting it off from certain
squares. Various names are given to particular types of interference, among
them
Grimshaw,
Novotny, anti-Bristol, Holzhausen,
Wurzburg-Plachutta and
Plachutta.
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Key - the first move of a solution. A problem which
unintentionally has more than one key is said to be cooked.
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Light - adjective applied to a problem which has a
relatively small number of pieces in the initial position. Lightness is
usually desirable in the interests of economy.
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Maximummer - a problem in which black must make the
geometrically longest moves available to him, as measured from square-centre
to square-centre. If two or more longest moves of equal length are available,
black may choose between them. This stipulation is most often attached to
selfmates.
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Meredith - a problem with no less than eight and no more
than twelve pieces on the board in the starting position. A problem with less
than eight pieces is a miniature.
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Miniature - a problem with no more than seven pieces on
the board in the initial position.
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More-mover - a directmate with the stipulation
"white to move and checkmate black in no more than n moves against any
defence" where n is greater than 3. In composition tourneys, there are often
separate classes for more-movers, two-movers and three-movers
(as well as classes for helpmates, selfmates and others).
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Mutate - a type of block problem in which at
least one mate in the set play is changed following the key.
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Novotny - a sacrificed white piece can be taken by two
differently-moving black pieces--whichever piece makes the capture, it
interferes with the other. Essentially a
Grimshaw brought about by a white sacrifice on the critical square.
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Phase (of play) - play after the key, after
tries and set play each constitutes a phase of play. A
problem with set play is said to have two phases (the set play being
one phase, the post-key play being another); a problem with three
tries would be a four phase problem (each try being one phase, with
the post-key play the fourth). Play in different phases will sometimes relate
to each other.
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Pickaninny - a problem in which, at some point in the solution, a
black pawn on its starting square makes each of it's four possible moves
(forward one square, forward two squares, capture to the left and capture to
the right). If the same behaviour is exhibited by a white pawn, it is an
albino.
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Plachutta - a sacrificed white piece can be taken by two
similarly-moving black pieces--whichever piece makes the capture, it
interferes with the other. Essentially a pair of
Holzhausen interferences (or a
Warzburg-Plachutta interference) brought about by a white sacrifice
on the critical square.
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Post-key play - the play following the key, that
is, the lines of play which fulfill the stipulation of the problem. This is
opposed to set play and virtual play (both of which may also
be important elements in the attractiveness of a problem).
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Proof game - a type of problem in which the job of the
solver is to construct a game of a given number of moves in which the final
position is the one given by the composer. A kind of retrograde analysis.
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Reflexmate - a selfmate in which both sides must
deliver checkmate if they are able to do when it is their move. A problem
where this stipulation applies only to black is a semi-reflexmate.
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Retrograde analysis, retroanalysis - deduction of the
move or moves leading up to a given position. A problem may be completely made
up of retrograde analysis (as in a proof game, or a problem in which
the task is to determine black's last move, for example), or it may be a part
of some larger problem (for example, it may be necessary to determine that
black has moved his king leading up to a given position, meaning he is unable
to castle, and thus rendering correct a solution which would be otherwise
incorrect).
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Round trip - a piece leaves a square, and then later in
the solution returns to it by a circuitous route (for example, a rook moves
e3-g3-g5-e5-e3). Compare with switchback, in which the route taken to
the original square is direct.
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S - in
algebraic notation, the letter N is usually used to indicate the
knight. In chess problems, however, the letter S (standing for
Springer, the German name for the knight) is often used instead, with N
instead being reserved for the popular
fairy piece, the nightrider.
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Selfmate - a type of problem where white forces black to
mate him against black's will within a specified number of moves.
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Series-mover - a problem in which one side makes a series
of moves without reply.
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Set play - play which would be possible from the initial
position of a problem if it was the other player to move first. For example,
in a directmate, set play consists of lines of play starting
with a black move (rather than a white move). When set play exists, the
key move may be something which does not change the set play lines, in
which case the problem is a complete block, or the lines in the set
play may change, in which case the problem is a mutate. Set play is
one phase of play.
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Switchback - a piece leaves a square, and then later in
the solution returns to it by the same route (for example, a rook moves
e3-e5-e3). Compare with round trip, in which the route taken back to
the original square is circuitous.
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Theme: the underlying idea of a problem, which gives it
logic, coherence and beauty.
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Threat - a move or variation which white will play
(usually following his key) if black does nothing to defend against
it. Problems which do not have threats following the key are blocks.
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Three-mover - a problem with the stipulation "white to
move and checkmate black in no more than three moves against any defence". In
composition tourneys, there are often separate classes for three-movers,
two-movers and more-movers (as well as classes for helpmates,
selfmates and others).
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Try - a move which almost solves a problem, but is
defeated by a single black defence, as opposed to the key (which
actually does solve the problem). Variations after tries are called
virtual play and may be an important part of what makes some problems
pleasing.
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Twin - two or more problems which are slight variations
on each other, composed by the same person. The variation is usually brought
about by adding, removing or moving a piece in the initial setup.
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Two-mover - a problem with the stipulation "white to move
and checkmate black in two moves against any defence". In composition
tourneys, there are often separate classes for two-movers, three-movers
and more-movers (as well as classes for helpmates,
selfmates and others).
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Version - said of a problem which is an adaptation of an
earlier one (it may have been altered to improve its economy or to
eliminate a cook).
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Virtual play - the play following a try, as
opposed to set play and post-key play.
