The Game of Laskers, Other Checker Variations, and Links
Regarding Mathematics and Chess
A checker game invented by Emanuel Lasker, Ph.D.
offers a domain where a succession of visual patterns must be manipulated.
(Dr. Lasker is known in mathematics and philosophy. He studied under Hilbert
and was awarded the Ph.D. in 1902. He became
World Chess Champion 1894; held the World Chess Championship until 1921; and
is considered by many to be the greatest chess player ever.)
In this game pieces are
stacked. Here side indicates red or black, i.e., the two
players. The game has an interesting nature: side-change can result from
captures. This is so because a jumped checker isn't
removed from the board as in the ordinary game. Instead a jumped stack of
checkers often remains on the board because the jump only removes
the top checker, which is carried off at the bottom of the jumping
Each checker-stack-entity is a piece. Its motion is under the control
of the side with the same color as the top checker. In any jump only the
highest checker is carried off under the conqueror.
The top checker of a stack is flipped over when a piece
reaches the eighth rank. This makes a crown show, and leads the piece
under it to act like a king in ordinary checkers. In other words
the piece can move backwards as well as forwards. That continues
until it is jumped, causing the top checker to go with its
All jumps are
forced (an offered jump must be taken unless there is another jump
available; double-jumps must be taken even if it would be advantageous
to cease after a single jump). Ordinary-checker rules apply. A game ends when one side cannot move.
[Seeing the king/ordinary-distinction is easier if liquid white-out outlines each crown.]
Lasker describes a 7x7 board with 22 pieces that follows this system.
That reference as HTML was transcribed by Peter Billam from a PDF scan
of the original.