IRĀNŠAHRI, ABU’L-ʿABBĀS MOḤAMMAD b. Moḥammad (fl. 2nd half 3rd/9th cent.), mathematician, natural scientist, historian of religion, astronomer, philosopher, and author. He was from Nišāpur, the city known also as Irānšahr (Moqaddasi, pp. 299-300; Ebn Faqih, p. 321), hence his title Irānšahri. Nāṣer-e Ḵosrow mentions him as the teacher of Moḥammad b. Zakariyāʾ Rāzi (b. 251/865), and Abu Rayḥān Biruni, who calls him an objective, reliable scholar, refers to him in connection with a solar eclipse in 259/873 (Biruni, 1958, tr., I, pp. 6-7; Minovi, pp. 32, 35-38). According to Abu’l-Maʿāli, the author of Bayān al-adyān, Irānšahri considered himself a prophet and had a book in Persian, which he claimed to be divine revelation, revealed to him by an angel called Hasti (Existence) to replace the Qurʾān (Abu’l-Maʿāli, ed. Danešpažuh, pp. 306-7). He believed in the unity of all religions and considered existing differences among them the results of special interests (ḡarażµ) of their followers. He said that God took covenant from light and darkness on the days of Nowruz and Mehragān (Biruni, 1878, p. 222; ed. Aḏkāʾi, p. 273), which seems to reflect Zurvanite influence. According to Nāṣer-e Ḵosrow, Irānšahri had expressed philosophical concepts in religious terms in such books as Ketāb-e jalil and Ketāb-e aṯir, and had led people to the true religion and the understanding of monotheism (tawḥid). Irānšahri maintained that God was always a creator (ṣāneʿ), and there was not a time when he was non-creative (u-rā ṣonʿ nabud) before He turned into being creative. Since it is requisite that He always be creator, then it is necessary for that in which His creation appeared to be eternal (qadim). His creation makes its appearance (padid-āyanda ast) in Matter (hayulā), and therefore, Matter, a sign of the apparent power of God, is eternal; and since Matter, which is eternal, requires the existence of Space (makān), it follows that Space should be eternal too. Irānšahri also said that time, world, and duration (zamān dahr wa moddat) are names whose meanings are derived from the same substance (jawhar). Time, a substance in motion and restless (jawhar-e ravanda wa biqarār), is the sign of God’s knowledge, in the same way that Space is the sign of His power; motion is the sign of His action, and the being (jesm) is the sign of His ability, and every one of these signs is infinite and eternal. Void (ḵalāʾ), that is Absolute Space (makān-e moṭlaq), is God’s power, an apparent power that contains all potentials (maqdurāt; Nāṣer-e Ḵosrow, 1960, pp. 69, 72, 77; Minovi, pp. 36-38).

Iranšahri did not belong to any current religion of the time; he believed in the religion that he himself had contrived and advocated. He was the author of several books and treatises in Arabic and in Persian, some of which are mentioned in passing by Biruni and Nāṣer-e Ḵosrow, but they are all lost (e.g., Masāʾel al-ṭabiʿa, Maqālāt, Jalil, Aṯir; see Biruni, 1948, p. 15; idem, 1958, p. 4; Nāṣer-e Ḵosrow, 1923, p. 98). According to Biruni, he gave an objective, accurate account of Judaism and Christianity and of the contents of the Torah and the Gospels, and also provided a good description of the Manicheans and their doctrine, but his accounts of the religions of India and shamanism left a good deal to be desired (Biruni, 1958, pp. 2-6; Abu’l-Maʿāli, ed. Dānešpažuh, pp. 306-7; Minovi, pp. 32-33, 35-36).

Given the positive remarks of Biruni and Nāṣer-e Ḵosrow, it is surprising that Irānšahri is hardly mentioned in later sources, including the works of Rāzi, who had been a student of Irānšahri and, according to Nāṣer-e Ḵosrow, had used Irānšahri’s ideas in a distorted form to pretend that they were all his own (Nāṣer-e Ḵosrow, 1923, pp. 98, 102, 110; 1960, p. 72; Minovi, pp. 36-38). One may also speculate that Irānšahri had been the source of much of the information provided by Rāzi on the beliefs of Indians and sects such as Dayṣāniya, Mo-ḥammera, and Mannāniya (Moḥaqqeq, p. 19). 


Abu’l-Maʿāli Moḥammad b. ʿObayd-Allāh, Bayān al-adyān, ed. Moḥammad Dabirsiāqi, Tehran, 1997; fifth chapter, ed. Moḥammad-Taqi Dānešpažuh as “Bāb-e panjom az ketāb-e Bayān al-adyān,” FIZ 10, 1962, pp. 282-318.

ʿAyn-al-Qożāt Hamadāni, Nāmahā-ye ʿAyn-al-Qożāt, ed. ʿAli-Naqi Monzawi and ʿAfif ʿOsayrān, 3 vols., Tehran, 1998, Monzawi’s Introd., pp. 161-94.

Abu Rayḥān Biruni, al-Āṯār al-bāqia ʿan al-qorun al-ḵālia, ed. C. Eduard Sachau as Chronologie orientalischer Vöker, Leipzig, 1878; ed. Parviz Aḏkāʾi, Tehran, 2001; comm., pp. 659-61.

Idem, Efrād al-maqāl fi amr al-ẓelāl, Hyderabad, 1948; tr, Edward Stewart Kennedy as The Exhaustive Treatise on Shadows, 2 vols., Aleppo, 1976.

Idem, al-Qānun al-masʿudi, 3 vols., Hyderabad, 1955.

Idem, Taḥqiq mā le’l-Hend men maqula maqbula fi’l-ʿaql aw marḏula, Hyderabad, 1958; tr. Edward C. Sachau as Albiruni’s India, 2 vols., London, 1910.

Ḥamid Ḥamid, “Kušeš-i dar bāz-sāzi-e andiša-ye ʿAbu’l-ʿAbbās Irānšahri,” Irān-šenāsi/Iranshenasi 12/4, 2000, pp. 835-43.

Mahdi Moḥaqqeq, “Irānšahri,” in idem, Filsuf-e Reyy: Moḥammad b. Zakariyāʾ Rāzi, Tehran, 1974, pp. 15-19.

Mojtabā Minovi, “Abu’l-ʿAbbās Irānšahri,” MDAM 1, 1965, pp. 133-39; repr. in idem, Naqd-e ḥāl, Tehran, 1977, pp. 32-40.

Nāṣer-e Ḵosrow, Zād al-mosāferin, ed. Moḥammad Baḏl-al-Raḥmān, Berlin, 1923; ed. ʿAli Qawim, Tehran, 1960.

Baron Victor Romanovich Rosen, Les manuscrits persans de L’institut des langues orientales, Saint-Pétersbourg, 1886, pp. 300-317.

(Dariush Kargar and EIr)

Originally Published: December 15, 2006

Last Updated: March 30, 2012

This article is available in print.
Vol. XIII, Fasc. 5, pp. 539-540

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Dariush Kargar and EIr, “IRĀNŠAHRI,” Encyclopaedia Iranica, XIII/5, pp. 539-540, available online at (accessed on 30 December 2012).