Elaheh Kheirandish

Science and Mithāl: Demonstrations in Arabic and Persian Scientific Traditions

Addressing the Arabic and Persian scientific traditions in eastern Islamic lands, this study focuses on the nature and place of demonstrations in optics and mechanics, sub-disciplines of geometry. A focus on the comparative context of demonstrations facilitates clearer understanding of local coordinates that affected the development of these fields, which are shown to have had distinct, and sometimes opposite, cases of transmission and application in Islamic and European lands. Sample demonstrations are presented in an appendix to highlight the concept and terminology of “mithāl” to identify shifts from geometrical to experimental methods in the case of optics, and from physical productions to model duplications in the case of mechanics.

The Arabic Tradition

The sources for the study of the Arabic tradition of Euclidean optics include, in addition to the Arabic versions already introduced [see The Arabic Versions, pp. xix—xxv, and List I, pp. xxxiv—xliv)], a set of supplementary texts, which contain besides optics proper (al-manāzir) material related to neighboring disciplines, from catoptrics (al-marāyā) to surveying (al-misāha) [see List II, pp. xlv—liii].17 These texts, which span the long chronological period of close to a millennium and a wide geographical area from Baghdad to Calcutta,18 date from a period shortly after the Arabic translation of Euclid’s Optics (ca. 212/827—828), a text upon which many are directly dependent.

Footprints of "experiment" in early Arabic optics.

This study traces the early developments of the concept of experiment with a view of extending the subject in both content and approach. It extends the content of the subject slightly backward, prior to the methodological breakthroughs of the Optics of Ibn al-Haytham (Alhazen or Alhacen, d. ca. 1040), which are credited as a significant landmark in the history of experimental science. And it extends the approach to the subject slightly forward, from the premise that early science was largely carried out in books, to a close examination of the books through which the footprints of experiment may be traced. The point of departure is the Optics of Ahmad ibn Ī;sā, a revealing text for the early developments of concepts such as demonstration and experiment, and one through which some modern discussions are examined and extended with reference to this and other historical sources.

Sciences, Crafts, and the Production of Knowledge: Iran and Eastern Islamic Lands (ca. 184–1153 AH/800–1740 CE)

Two successive sessions held at the Sixth Biennial Conference of Iranian Studies in London (3–5 August 2006) mark the occasion for publishing the present volume. The organizers and session chairs, Elaheh Kheirandish and Carol Bier (“Geometry in Medieval Persian Sciences and the Arts”) and Najm al-Din Yousefi (“Science and Technology in Medieval and Early Modern Iran”) found sufficient common ground among their diverse subjects and approaches to collaborate on this special issue of Iranian Studies, with two immediate objectives:

Part One: The “Elements” of Sciences and Crafts

Among the sciences and crafts of eastern Islamic lands, geometry emerges as a subject that transcends disciplinary boundaries with which we are familiar today. TheElements and Optics of Euclid (ca. 300 BCE), the Conics of Appollonios (third century BCE), and theMechanics of Heron (first century CE) and Pappus of Alexandria (fourth century CE), highlight the prominence of geometry in the sciences. Apart from the textual tradition and the written transmission of knowledge, a glance at illustrations and diagrams, scientific instruments, illuminated manuscripts, and monuments of art and architecture reminds us of the significance of geometry in textual and visual traditions alike. The close relationship of visual evidence to textual sources immediately calls into question the contemporary paradigm that segregates sciences from crafts as independent endeavors that are ontologically discrete. Rather, geometry in Arabic and Persian traditions, as well as in the arts and architecture, incontrovertibly links the sciences and crafts in the production of knowledge. Such a unified perspective breaks down contemporary dichotomies by finding expression within both the historical textual tradition and extant monuments. “The ‘Elements’ of Sciences and Crafts,” adopted as the title of the present section, is itself inspired by the historical analogy between the classic Elements (Stoicheia) of Geometry and the letters of the alphabet in a given language. The kinds of interaction that existed, not just between early sciences and crafts, but also among scientists and craftsmen, is a subject that has received recent attention, sparking considerable discussion with reference to “mathematics and the arts” and “mathematics and artisans.” Primary sources may contribute to a better understanding of the nature of such possible encounters.

The "Fluctuating Fortunes of Scholarship": A Very Late Review Occasioned by a Fallen Book

The last published paper of the late David Jackson, “Scholarship in Abbasid Baghdad with Special Reference to Greek Mechanics in Arabic” (1987-8), closes with a comment on the “fluctuating fortunes of scholarship in Abbasid Baghdad.” One may use similar words concerning scholarship on Abbasid Baghdad. For the longest time—almost twenty years since its earliest presentation in Venice (1986)—Jackson’s paper has remained unknown and unacknowledged despite its direct relevance to several major studies published since, on both early science and Abbasid Baghdad. As a misfortune of a different form and magnitude, Jackson’s paper was itself published between a doctoral thesis, which was never published (Cambridge University, 1970), and a book that his unexpected passing away in 2001prevented from ever being published1—leaving two short publications in the long period in between.2

Description and Analysis of Manuscripts

There are at least five extant copies representing the manuscript tradition of the early Arabic version. The following description and analysis is based on the available copies [five of the six reported ones], to be supplemented with a reproduction of opening and closing pages [see Manuscript Plates, pp. 232–241].

Editorial Procedures and Apparatus

The critical edition of Kitāb Uglīdis fi Ikhtilāf al-manazir in volume I has been prepared from all five available manuscript copies, denoted here as m 1—m5 [see Description, pp. xxvi—xvii, and List I, p. xxxiv]. The establishment of the text (M) is primarily based on ml [dated 625H], a copy likely to be closest to the original composition, as suggested by some identifiable features including the title [the variants of the other four manuscripts, m2—m5, dated 692H, 600H, 751H, and ca. 680H respectively, are presented in the critical apparatus]. The odd-numbered manuscripts, m 1, m3 and m5, would all qualify for such a selection. Not only do their titles as Kitdb Uglidis f Ikhtilaf al-manazir refer to the name of Euclid, as do those with the short form al-Mandzir, but the association with “an old translation” (al-nagl al-qadim) is more explicit in their case [see Summary and Commentary: Title, v. 2, p. 2, n. 43]. The curious description of the visual rays as “unequal in distances and magnitudes” (mukhtalifat al-ab ad wa al-magadir) in the set m2, m4 [see Description, pp. xxvi—xxvii] and especially the statement in one of them (m2) regarding the “poor” (saqim), “obscure” (mughlaq) and “cut off’ (batr) nature of its ”original“ (as1) [including the alternative readings in Description, p. xxvi] further point to members of the odd set (m1, m3, m5) as more authentic and complete texts.

The Arabic Versions

The corpus of sources for the study of the Arabic tradition of Euclidean optics is formed by a few genres of works. First there are the founding texts of the tradition, namely the Arabic versions of the Euclidean text, representing a major part of the original Greek as found in Heiberg’s Euclidis Optica. 1 Then there is a set of dependent texts, which together with the Arabic versions of the text, form the tradition as it developed in the four centuries between and occasionally beyond the Arabic versions of the 3rd/9th and 7th/13th centuries. And finally there is a series of related texts, reflective of or responsive to different aspects of Euclidean optics, through which the tradition may be further studied or its chronological and geographical boundaries further extended.

Kitāb Uqlīdis fī Ikhtilāf al-manāẓir

In the Name of God, the Compassionate, the Merciful. The Book of Euclid on the Difference of Aspects