Isidore of Miletus

Lore & Background

Isidore of Miletus was a renowned scientist and mathematician before Emperor Justinian I hired him. Isidorus taught stereometry and physics at the universities of Alexandria and then of Constantinople, and wrote a commentary on an older treatise on vaulting. Eutocius together with Isidore studied Archimedes' work. Isidore is also renowned for producing the first comprehensive compilation of Archimedes' work. A majority of Isidore's preserved work are his edits and commentaries on older Greek mathematical texts. For example, Isidore is known to have revised and checked some of Archimedes' works and also Book XV of Euclid's elements. Claims from Alan Cameron have been made about a hypothetical 'School of Isidore'. Between his work on architectural exploits, Isidore taught about math and geometry of the time. The School of Isidore is supported more by the presence of his teachings in much of his students (such as Eutocious) works rather than his own writings. In an edit of the fifteenth book of Euclid's Elements, for instance, the editor quotes Isidore, but then proceeds to explain that Isidore did not publish much of his work himself. Instead, he taught, and once he himself could understand the material, did not see a need to write it down. It is because of this that Cameron claims that Isidore helped to revitalize interest in ancient mathematicians in Constantinople and Alexandria circa 510. In addition to editing the works of others, Isidore is known to have written his own commentary on Hero of Alexandria's 'On Vaulting', which discussed aspects of vault construction and design in relation to geometry. While this commentary is lost, Eutocius makes mention of it in his own writings. It is when referring to this work that Eutocius credits Isidore with designing a special compass for the purpose of drawing parabolas. Isidore's invention allowed for the drawing of parabolas with a greater level accuracy than that of which many previous methods were capable. From Eutocius (or his copyist) it is believed that one notable use for Isidores invention was to visually solve the problem of doubling the volume of a cube. This was said to be done by drawing two parabolas and finding the point where they intersect. In addition to their mathematical applications, Isidore is believed to have highlighted the uses of applying the use of parabolas to the construction of vaults

Reader's Guide

Emperor Justinian I appointed his architects to rebuild the Hagia Sophia following his victory over protesters within the capital city of the Roman Empire, Constantinople. The first basilica was completed in 360 and remodelled from 404 to 415, but had been damaged in 532 in the course of the Nika Riot. The rival factions of Constantinople's populace, the Blues and Greens, opposed each other in the chariot races at the Hippodrome and often resorted to violence. During the Nika Riot, more than thirty thousand people were killed. Emperor Justinian I ensured that his new structure would not be burned down, like its predecessors, by commissioning architects that would build the church mainly out of stone, rather than wood. The construction of the Hagia Sophia began so fast after the riots were quelled that many think that Justinian had his architects begin planning it before the riots even stopped. Isidore of Miletus and Anthemius of Tralles originally planned on a main hall of the Hagia Sophia that measured 70 by 75 metres (230 x 250 ft), making it the largest church in Constantinople, but the original dome was nearly 6 metres (20 ft) lower than it was constructed. Although Isidore of Miletus and Anthemius of Tralles were not formally educated in architecture, they were scientists who could organize the logistics of drawing thousands of labourers and unprecedented loads of rare raw materials from around the Roman Empire to construct the Hagia Sophia for Emperor Justinian I. Isidore and Anthemius obtained stone from as far away as Egypt, Syria, and Libya, and columns from several temples in Rome. It is believed that Isidore did much of the work on the domes of the Hagia Sophia due to his extensive work on vaults, and his commentary, 'On Vaulting'. The Hagia Sophia architects innovatively combined the longitudinal structure of a Roman basilica and the central plan of a drum-supported dome, in order to withstand the high magnitude earthquakes of the Marmara region. However, in May 558, little more than 20 years after the Church’s dedication, following the earthquakes of August 553 and December 557, parts of the central dome and its supporting structure system collapsed. The Hagia Sophia was repeatedly cracked by earthquakes and was quickly repaired. Isidore of Miletus’ nephew, Isidore the Younger, introduced the new dome design that can be viewed in the Hagia Sophi

Did You Know?

• Isidore of Miletus taught stereometry and physics at the universities of Alexandria and Constantinople.
• He produced the first comprehensive compilation of Archimedes' work.
• Eutocius credits Isidore with designing a special compass for drawing parabolas.
• Isidore's nephew, Isidore the Younger, redesigned the dome of Hagia Sophia after an earthquake.