Dardi da Pisa; Antonio de’ Mazzinghi; The Florentine Tratato sopra l’arte della arismetricha; The Florentine encyclopedias; An aside on the regula recta
The end and aftermath of the abbacus tradition
A Modena manuscript; Nicolas Chuquet and Étienne de la Roche; Pacioli and Pacioli; del Sodo
Algebra in German land
Eclectic beginnings; Andreas Alexander; Heinrich Schreyber; Christoph Rudolff and later coß; Jacques Peletier
Chapter III. Abbreviations, glyphs, symbols and symbolic calculation
The Maghreb symbolism
The Italian beginnings
Biagio “il vecchio”; Dardi and Alcibra amuchabile; The Liber restauracionis
Late 14th and 15th-century algebra
Late-14th-century Florence; A collective work from 1429; The Florentine encyclopedias; The Modena manuscript; Chuquet; Giovanni del Sodo
Algebra in Italian print
Pacioli; Three 16th-century Italian writers
German notations
The German and Latin algebras of Dresden, C 80; Alexander; Schreyber, Rudolff and later coß
French algebraic writings
Chapter IV. Embedding and parenthesis function
Composite radicands
Dardi; Antonio – two levels; Chuquet and de la Roche; Mennher; Cardano, Tartaglia and Bombelli
The substitutes for and a dubious step toward a general parenthesis function
Viète
Chapter V. Several unknowns
Several unknowns in Arabic and post-Arabic algebra
Arabic use; Liber mahameleth; Fibonacci
Abbacus occurrences of several unknowns around 1400
Antonio de’ Mazzinghi; The Florentine Tratato
The Florentine abbacus encyclopedias
The Ottoboniano Praticha; Benedetto
Pacioli, Chuquet and de la Roche
Coß
Stifel; Immediate impact in Germany; Mennher; French writers after de la Roche
Chapter VI. The transition to incipient modern algebra
Mathematical cultures
The raison-d’être and format of abbacus algebra; Scholastic mathematics; Humanist mathematics; Agonistic mathematics, once again
An apparently minor leap with immense consequences
Algebra as Descartes knew it; Viète’s “defiled and polluted” algebra; Receiving abstract coefficients as a gift not asked for; Geometry and algebra with one unknown; Viète’s abstract coefficients
Descartes’ other innovation
Newton and Wallis; The truly general parenthesis
Coda
Bibliography
Index
Jens Egede Høyrup, born in 1943 in Copenhagen, is a Danish historian of mathematics, specializing in pre-modern and early modern mathematics, ancient Mesopotamian mathematics and the abbacus tradition in particular. He is especially known for his interpretation of what has often been referred to as Old Babylonian “algebra” as consisting of concrete, geometric manipulations.