The Blog

A library of stories and sources

From early cities and scripts to beliefs, science, and contested history. Pick a subject, read a guide, and open the material behind it.

Every guide links its sources. We mark what comes from a surviving object, what belongs to a tradition, and what remains a hypothesis.

2 of 96 source guides

Alexandria, Baghdad, Toledo, Saragossa 2nd century CE – 1381 CE

The Almagest: one book, four cities, a thousand years

Ptolemy’s astronomy moved through Arabic and Latin translations. A manuscript from Zaragoza marks one stop on a journey spanning more than a thousand years.

Paris and Toledo 15th century CE

Euclid in Latin: a fifteenth-century witness

A fifteenth-century Paris manuscript preserves Euclid in Latin, translated from Arabic. The copy, the translation, and Euclid’s life belong to different dates.