This is a book about many things: Sharaf al-Din ʿAli Yazdi (d. 1454) as a multifaceted intellectual; Yazdi's historiography and political theology; intersecting intellectual networks in the first half of the 15th century; prevalence of occult sciences (especially the science of letters [ʿilm al-ḥurūf]) in that period; intellectuals’ agency vis-à-vis their Turko-Mongol patrons (above all Timurid princes); Timurid appanage politics; and finally the 15th century as a distinct era in history, especially of the Persianate world. İlker Evrim Binbaş presents original discussions on all these topics based on his extensive reading of primary sources in Persian, Arabic, Turkic, and some European languages, many still in manuscript form. The florid and convoluted style characterizing Yazdi's writings is also worth special mention, as this important book would have never come into existence had it not been for Binbaş’ perseverant conversation with Yazdi's defying texts. All in all, Binbaş must be congratulated on contributing this heavy and profound piece of scholarship to the field.

Binbaş devotes the first half of the book to reconstructing the chronological outline of Yazdi's career and to elucidating different connections that Yazdi established throughout his life. The most highlighted is the informal network of intellectuals who shared the belief in the supreme importance of the science of letters as a science with fundamental ontological dimension. Those intellectuals, some of whom referred to themselves by the term ikhwān al-ṣafā (brethren of purity), held that the words and phrases closely linked to every existent in this phenomenal world (and the world itself), typically the existent's name, represented the essence and reality of that existent, which could be understood only by the intellectual-spiritual elites by means of numerical analysis (abjad calculation) of the letters constituting them. Starting the story with Sayyid Husayn Akhlati in Cairo, Binbaş uncovers the ikhwān al-ṣafā’s network that extended not only to the domains under Timurid rule (with Saʾin al-Din Turka and Yazdi himself) but also to the realms of the Ottomans (with Shaykh Bedreddin and ʿAbd al-Rahman al-Bistami). It is also shown that the intellectual ethos of the ikhwān al-ṣafā was widely shared, albeit to differing extents, by other intellectuals of the period. The ikhwān al-ṣafā’s adherence to the occultist worldview had substantial political significance. Their affirmative yet elitist and esoteric approach to the human capacity to grasp the reality was compatible with the idea of a heavenly ordained absolutist rule. From here arose the various modes of mingling that the ikhwān al-ṣafā came to have with politics and political authorities, the latter of which included, above all, the courts of Timurid princes with their respective constitutional programs.

Thus, Binbaş’s discussion of Yazdi's historiographical project and political theology, in the second half of the book, is characterized by his stance to acknowledge full agency on the part of Yazdi in his dealings with his Timurid patrons. Binbaş reconstructs the timeline of Yazdi's historiographical activities and concludes that Yazdi's extant histories represent fragments produced at different junctures of an ever-transforming historiographical project. Based on this finding, Binbaş discusses the evolution of Yazdi's political theology as it was propounded in his different histories, that is, at different points through his career. Binbaş finds here that the concept of a dual kingship (external and internal, to put it simply) was a continuing feature of Yazdi's political theology. This unchanging backbone throughout the evolution of Yazdi's political theology serves Binbaş as a manifestation of Yazdi's agency as an intellectual, or his intellectual authority, in his dealings with his patrons.

The existence of the intellectual network that Binbaş discusses was noted previously (Jean Aubin and Shiro Ando). But, the central place that occult sciences, especially the science of letters, held in the Weltanschauung of the intellectuals constituting that network and, more importantly, the significance of that very fact for our understanding of intellectual and political landscapes of the period, had not been adequately recognized. For better or worse, historians of the 15th century (and more), in their discussions of quite a few subjects, will be far less entitled to comfortably put aside occult sciences (a difficult subject to deal with, indeed!) as something peripheral. Binbaş’s contribution to “Yazdi studies” is no less significant (p. 202). No reader will finish the book with the wrong idea of Yazdi being a mere historian. At the same time, it is nonetheless clear that Binbaş’s fundamental interest in Yazdi lies in his facet as a historian and in elucidating his historiographical activities. In this context, Binbaş’s discussion of other aspects of Yazdi the intellectual has enabled him to offer a fresh reappraisal of what that multifaceted historian with full intellectual authority was trying to do when writing histories.

It must, however, be noted that Intellectual Networks of Timurid Iran is not an easy book to read. Apparently, one of the reasons for the difficulty was the word count limit that Binbaş managed to meet by cutting introductory sentences at different levels that would have helped the reader to follow his arguments more confidently. The following comments and questions may perhaps have been caused by the same reason.

My first question concerns Binbaş’s appraisal of the impact of the ikhwān al-ṣafā’s ideas on the intellectual currents of the following periods. One important thesis Binbaş puts forward is that the network of the ikhwān al-ṣafā lost its power around the middle of the 15th century and that it was the formal Sufi networks, above all the Naqshbandis, that came to dominate the scene in the latter half of that century. Then, was the ikhwān al-ṣafā an ephemeral phenomenon that left no substantial mid- or long-term intellectual impacts? I would like to know Binbaş’s idea, as that may also clarify to what extent he sees a continuity between late medieval and early modern versions of absolutism (Azfar Moin). Also, Binbaş’s use of the term “republic of letters,” the role that occult sciences played therein, and Binbaş’s tone in the introduction all made me interested in reading his comparison with the development in the early modern West, which is absent in the book. Here, it may also be worth noting that it was not clear to me if Binbaş considered the first half of the 15th century late medieval or early modern in any consistent way (see e.g., pp. 2, 112, 152, 250).

It is when discussing the evolution of Yazdi's political theology and his idea of dual kingship that Binbaş puts forward quite a few bold interpretations in a way not seen in the rest of the book. The interpretations are all in all intriguing, but in several places more argumentations to support them would be helpful. A case in point is the discussion regarding Yazdi's reference to “Sultan-Mahmud” as Shahrukh's name at birth (pp. 265–69). I would like to have known whether the linking of that name with that of Timur's puppet khan by the same name which allows Binbaş to state “the two bodies of Sulṭān-Maḥmūd and Timur were transformed into the king's two bodies in the corporeal and kingly existence of Shāhrukh” was based solely on association or had textual basis (p. 268). More generally, I would love to learn if (and how) the dualistic framework characterizing Yazdi's political theology has to do with occult sciences generally or the science of letters in particular into which Yazdi was deeply steeped.

Intellectual Networks in Timurid Iran is not an easy book also because it presents many original and profound ideas that require us to ponder and cross-examine even before posing questions. The reward promised to those who complete the book is therefore immense. Students in the related fields are urged to enter into dialogue with this important book for their own personal sake and for the sake of the advancement of the related fields through ensuing dialogues.