Jens Høyrup (*1943): educated as a physicist at Copenhagen University. From 1973 he taught first in the domain of social, then human sciences, at Roskilde University, Denmark, until he retired in 2005. Much of his research has dealt with the conceptual, cultural and social history of pre-Modern mathematics – lately also, as in the final chapters of the present book, of Early Modern mathematics.

• Preface.- Contents.- Introduction- The home of abbacus mathematics: the abbacus school.- An example: Jacopo da Firenze's Tractatus algorismi, the short version.- Fibonacci and the Fibonacci story- The real story in select detail.- Abbacus goes into print and abroad318.- A double conclusion.- Sigla.- Bibliography- Name, subject and source index.

Jens Høyrup (*1943): educated as a physicist at Copenhagen University. From 1973 he taught first in the domain of social, then human sciences, at Roskilde University, Denmark, until he retired in 2005. Much of his research has dealt with the conceptual, cultural and social history of pre-Modern mathematics – lately also, as in the final chapters of the present book, of Early Modern mathematics.

• Preface.- Contents.- Introduction- The home of abbacus mathematics: the abbacus school.- An example: Jacopo da Firenze's Tractatus algorismi, the short version.- Fibonacci and the Fibonacci story- The real story in select detail.- Abbacus goes into print and abroad318.- A double conclusion.- Sigla.- Bibliography- Name, subject and source index.

Jens Høyrup (*1943): educated as a physicist at Copenhagen University. From 1973 he taught first in the domain of social, then human sciences, at Roskilde University, Denmark, until he retired in 2005. Much of his research has dealt with the conceptual, cultural and social history of pre-Modern mathematics – lately also, as in the final chapters of the present book, of Early Modern mathematics.

• Preface.- Contents.- Introduction- The home of abbacus mathematics: the abbacus school.- An example: Jacopo da Firenze's Tractatus algorismi, the short version.- Fibonacci and the Fibonacci story- The real story in select detail.- Abbacus goes into print and abroad318.- A double conclusion.- Sigla.- Bibliography- Name, subject and source index.