Gernardus
13th-century mathematician
Gernardus was a 13th-century magister (master) and the author of the Latin arithmetical treatise Algorismus demonstratus. He belonged to the circle around Jordanus de Nemore at the University of Paris. His Algorismus was a popular text in the later Middle Ages, but largely ignored by early historians of mathematics. It is about 20,000 words in length and divided into two parts, Algorismus de integris on integers and Algorismus de minutiis on fractions. It uses letters in place of numbers for general examples. It belongs to the tradition of Boethius and it frequently cites Euclid. It probably made use of the pioneering works of Jordan, but itself contains nothing new.
The Algorismus is known from many manuscripts of the 13th through 16th centuries, but only one contains an attribution to Gernardus, who is otherwise unknown. A copy was made by Regiomontanus in Vienna, now part of manuscript 5203 of the national library. This copy was published by Johannes Schöner at Nuremberg in 1534.
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This entry incorporates text from “Gernardus” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.