The most reliable guide to the notoriously difficult mathematical game of medieval and Renaissance Europe

Boissière, Claude de. Nobilissimus et antiquissimus ludus Pythagoreus (qui Rythmomachia nominatur) in utilitatem & relaxationem studiosorum comparatus ad veram & facilem proprietatem & rationem numerorum assequendam, nunc tandem per Claudium Buxerium Delphinatem illustratus.

€ 12.500,00

First Latin edition, expanded from the original 1554 French one. "Boissière considered himself a mathematics teacher and used the game of Rythmomachia as a vehicle for teaching arithmetic" (Tomash). Rithmomachy, or the "Philosophers' Game", was a board-game popular from the Middle Ages through the end of the sixteenth century. Similar to chess but with every piece having a numerical value, it was an essential part of mathematical education for centuries. This volume, laying out the rules and offering a guide to playing, is distinctive for being one of only two known references to the sale of Rithmomachy boards and pieces, which are very poorly attested.

This treatise was the clearest guide to the notoriously complicated game from its heyday of popularity in the sixteenth century. Boissière attributes its origins to the ancient Greek mathematician Pythagoras, and uses it to illustrate a number of wide-ranging principles, from mathematical ratios and musical harmonies, which remain relevant today in fields from music theory to computing. This volume was owned in the early 19th century by the French polymath and amateur mathematician Claude-Marie Pillet, of whom Hoefer writes, "Logé dans un galetas, vêtu grotesquement de vieux habits achetés à la friperie, ne vivant que de pain sec ou d'aliments grossiers et de mauvais fruits, sans feu chez lui, sans chapeau dans les rues, il bornait ses dépenses à acheter des livres". It later was part of the illustrious Erwin Tomash Library on The History of Computing, which comprised books and manuscripts relevant to the subject from the twelfth century onwards.

In Rithmomachy, the board is divided into a grid, with the opposing players' pieces opposite one another. In addition to different types of pieces (round, square, triangle or the most powerful, pyramid), every piece has a numerical value, which determines how it interacts with and whether it can capture others. The game allows for multiple types of victories depending on the numerical outcomes. In spite of its alleged Pythagorean origins, Rithmomachy is first attested in the 11th century as a means of teaching the principles of mathematics in western European monastic schools. Roger Bacon, the great medieval scholar and scientist, recommended it to his students, and Sir Thomas More envisioned the inhabitants of Utopia as playing it for relaxation. In spite of its fame, Rithmomachy is poorly attested from material evidence, with no boards or pieces from the medieval or early modern period having been found. The game disappeared in the seventeenth century as new methods of teaching mathematics were developed. This volume, which on the title-page advises readers that sets can be purchased "in Palatio, apud Ioannem Gentil", is one of only two known references to physical Rithmomachy sets.

Claude de Boissière (fl. 1554-1608) was a mathematician and lecturer at the Collège Royal in Paris. His guide to Rithmomachy was first published in French in 1554; he issued a revised and augmented edition in 1556, which was then published in a Latin edition for an international educated audience. Rare, particularly on the private market: USTC lists 21 copies in institutional holdings, mainly in western Europe, while Rare Book Hub records only 3 other copies sold since 1978.

A testimony to the enduring creative potential of mathematics both for education and pleasure.