Sir

I'm afraid the Book Review of Jean-Luc Chabert's A History of Algorithms (Nature 403, 703; 2000) contains the same frequently made mistake pointed out by your correspondent S. Khochbin (Nature 405, 14; 2000) in another recent article.

The reviewer includes the Persian mathematician and scholar Nasir al-Din al-Tusi among Arab mathematicians. Nasir al-Din al-Tusi did write in Arabic (as well as Persian), but this is like saying Sir Isaac Newton was not English, because he wrote in Latin!

Nasir al-Din al-Tusi was born in Tus, a city in the northeast part of Iran, in the province of Khorasan, quite far from any Arab populations at the time, or even now.