Johannes Widmann

Johannes Widmann (also: John Weidemann, Weideman, Widman, Wideman, * 1460 in Eger, Bohemia; † after 1498 in Leipzig) was a lecturer at the University of Leipzig.

Widmann is registered in the winter semester 1480 in the Matrikelliste the University of Leipzig (as John Weideman de Egra ). For the financial statements as a bachelor in 1482 and Master in 1485 him the charges were because he was penniless, adopted.

Widman became famous through his book Mercantile Arithmetic or nimbly and hüpsche Rechenung auff all Kauffmanschafft, published in 1489 in Leipzig. This is the first book in which the and - symbols for the arithmetic operations plus and minus are used.

His arithmetic book from 1489 ( printed in Leipzig by Konrad tile stove) is the second oldest printed in Germany arithmetic book after the Bamberger arithmetic book by Ulrich Wagner ( 1482/83 ) and the third oldest printed book on arithmetic at all. It was dedicated Siegismund Altmann. Widmann's book was widely read and was reprinted until 1526, among others, in Pforzheim, Haguenau and Augsburg. Then it was overtaken by other arithmetic books such as those of Adam Ries and Jacob Köbel. After Kurt Vogel it surpassed its predecessor in the number and width of computational examples by far. As a source he used the Bamberger arithmetic book and the Algorismus ratisbonensis, an arithmetic book that originated around 1450 in the Benedictine monastery of St. Emmeran in Regensburg.

His lecture on algebra in 1486 is the first algebra course in Germany. The content is from student notes known (obtained in manuscripts in Dresden, Vienna, Munich). In addition, a manuscript exists in the possession of the State Library of Dresden from Widmann's possession ( Dresden Codex C 80 ), contains the texts on algebra, including a German algebra from the year 1471, a Latin algebra, which served as the basis of his lecture. The lecture dealt with the time when the Cossisten ( Algebra experts) usual equation 24 species, but also to prepare fraction arithmetic and ratio calculation.

Adam Ries learned Widmann's book (and the Dresden manuscript with algebra texts from Widmann's possession, now National Library Dresden) in the library of George Sturtz know in Erfurt, where Ries 1518-1522 was. Ries took over from the manuscript examples of his Coss (his Algebra manuscript ), but apparently knew ( Kurt Vogel ) is not the identity of the author of the manuscript.

After Kurt Vogel, he published alongside his arithmetic book anonymously algorithm integrorum cum Probis Annexis, linealis algorithm, algorithm minutiarum phisicarum, algorithm minutiarum vulgarium, Regula falsi apud philosopher antes augmenti et decrementi appellata and Tractatus proportionum Plusquam aureus. The writings probably published around 1495 in Leipzig.