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.

3 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.

Cracow, Padua, and Uppsala 14th–16th centuries CE

Bianchini’s tables in Copernicus’s hand: what is proven?

Copernicus copied planetary latitude tables in his own hand. It is a strong find, but does not by itself settle every question about how he used them.