The perfect compass: conics, movement and mathematics around the 10th century.

Thomas de Vittori (1)

1 LML - Laboratoire de Mathématiques de Lens

Geometry instruments certainly exist since men are interested in mathematics. These theoretical and practical tools are at the crossroads of the sensible world and mathematical abstractions. In the second half of the 10th century, the Arabic scholar al-Sijzı wrote a treatise on a new instrument: the perfect compass. At that time, several other mathematicians have studied this tool presumably invented by al-Quhı. Many works are now available in French and English translations. After an historical presentation of the perfect compass, this article deals with a few passages of al-Sijzı's treatise which show the importance of continuous tracing of curves and provide interesting elements on the role of instruments in the mathematical research process. All these texts can help to understand the importance of motion in geometry which can be easily simulated by geometry softwares and used in a geometry lesson or in teacher training sessions.

Keywords: history of mathematics; geometry

Domains: History and Overview [math.HO]; Education

Thomas de Vittori. The perfect compass: conics, movement and mathematics around the 10th century.. The perfect compass: conics, movement and mathematics around the 10th century., Jul 2009, Vienna, Austria. p.539-548. ⟨hal-00658217⟩