ON THE CONFLICT OF RITHMIMACHIA

original: De Conflictu Rithmimachie; a mathematical board game invented in the 11th century to teach Pythagorean number theory.

Whoever is skilled in arithmetic and desires to have knowledge of this invention should be certain that all species of the three mathematical genera—the multiple, the superparticular, and the superpartient superparticular (ratio of n+1:n, like 3:2); superpartient (ratio of n+m:n, where m > 1)—up to the tenfold proportion, are found in this conflict. They are established such that on one part of the board are those named from the even, and on the other, those from the odd.

The species of the multiple multiplicis; numbers that are direct multiples of another (e.g., 2, 4, 8) shall have their lawful movement forward, backward, to the right likewise and so and diagonally into the second space In Rithmimachia, "second" means the square immediately adjacent to the piece's starting position. The superparticular moves into the third space, and the superpartient into the fourth.

Whichever number from one side encounters another number of the same value through a hostile move original: hostractum; likely a contraction for hostis tractum, the path of an enemy, let it take that piece. And if numbers placed apart from the surrounding parts, which are multiplied or joined together, produce the same sum, let them take it. Or, if a value capable in adjacency original: triacencia; likely a corruption of adiacentia—both the foreign and its own, multiplied with its own—produces a foreign sum, let it take it.

On that part of the board where all species are named from the even, there is placed first the six This refers to the "Pyramid" piece, a composite piece made of several numbers. If it should strike its own base, for example 36 36 is the square of 6, often representing the base of a pyramid piece, or if whatever numbers in the adjacent field produce the sum of that base...