Three routes into Renaissance Italy.

A library and a lecture

Bardi's 2024 study of Regiomontanus's Paduan lecture of 1464 finds that Bessarion's collection preserved Islamic and Persian astronomical tables in high-quality manuscripts, that Bessarion's own education included Persian astronomy, and that Regiomontanus acknowledged Arabic astronomers and Persian tables in that lecture. The research case rates this bridge strongly documented, at 96, while noting the complete Ibn al-Shatir Mercury packet is not shown in that chain. British Journal for the History of Science ↗

A scholar in Venice

Langermann's study of Moses Galeano's compendium reports that it accurately summarizes Ibn al-Shatir's system and that Galeano was in Venice around 1500. The surviving copy, however, was made in 1539 and later revised by Galeano, so the research case rates as verified at 98 that it cannot be treated as a snapshot of what he knew in 1500. Aleph ↗

Galeano and Copernicus

Morrison's study places Galeano in the Veneto around 1500 in Jewish scholarly networks with Christian contacts, and states that direct contact with Copernicus is not proven. The research case therefore calls Galeano a strong partial-carrier candidate, at 90, but not a proven link. Isis ↗

A notebook in Mantua

Langermann's study of medieval Hebrew texts on the quadrature of the lune shows that Mordekhai Finzi copied a distinctive construction from Avner de Burgos's Meyashsher Aqov, a work that also contains a Tusi-couple proof. That Finzi read that proof is inferred rather than attested, so the research case rates it a plausible hypothesis, at 78. It calls Finzi an independent north-Italian route for Tusi-couple geometry, not for the full Mercury packet. Historia Mathematica ↗

Finzi's tables

Chabás and Goldstein add that Finzi produced a version of the Oxford Tables with radices for 1443 and the meridian of Mantua, surviving in a unique Hebrew manuscript. Evidence that he worked in scientific contact with Christian astronomers in northern Italy supports the picture of a real network. Journal for the History of Astronomy ↗

Two open gaps

The research case concludes at 95 that no single documented carrier explains the full technical packet, so it models multiple partial carriers. It names two unresolved gaps: a pre-1510 witness containing the complete Ibn al-Shatir Mercury packet, and a content-bearing access route into Copernicus. A targeted search has not found such a witness, and the case labels that a search-negative, not proof of absence.

A question to carry forward

Why is it more honest to say 'several partial routes' than to choose the most appealing single traveller? What would one new manuscript have to contain to change the answer?