 It is the second logician Ibn Khaldûn mentions who, it would seem, made more, and more substantive, changes to Avicennan logic: Afdaladdîn al-Khûnajî (d. 1249). His major work on logic, the Disclosure of Secrets about the Obscurities of Thoughts, has recently been edited (Khûnajî Kashf [2010], with a long introduction including a biography of this important logician, and an overview of some of his more important innovations). He was described, probably pretty loosely, as one of Râzî's students; Bar Hebraeus writes of a group who were famed as “authors of major works on logic and philosophy… [among them] Khûnajî in Cairo” (translated in Pococke 1663: 485.7–13 (Arabic)). The sense in which he could have been Râzî's student is presumably that he studied under someone who had studied under Râzî. It will be some time before we are able to assess Khûnajî's importance accurately; he seems to have exercised extraordinary influence, often taking a strong stand against both Râzî's position and Avicenna's. In their different ways, both the North African and the Eastern traditions of logic are strongly influenced by Khûnajî  (see section 1.6 below). 