Nasir al-Din al-Tusi
Avicenna’s philosophy stands up to its critics, and ethics covers the whole of life – personal character, the household and the state.
Placement
Persian polymath and astronomer of the Maragha observatory: defended Avicenna; his “Nasirean Ethics” remained a standard Persian work on ethics for centuries.
Key ideas
- Defense of Avicenna
- Ethics, household and politics
- The Tusi couple (astronomy)
Students: Qutb al-Din al-Shirazi
Influence
Influenced by 5
Aristotle
influenced by
Al-Tusi’s Persian logic, The Foundation of Acquisition (Asas al-iqtibas, 1244), treats the whole Aristotelian Organon, including rhetoric and poetics. Nasir al-Din al-Tusi, Asas al-iqtibas (1244); Encyclopaedia Iranica “Asas al-eqtebas”
Evidence: AI draft
Aristotle › 384–322 BCE
al-Farabi
influenced by
The political part of al-Tusi’s Nasirean Ethics (1235) drew on al-Farabi’s virtuous city and his classification of virtuous and ignorant cities. Nasir al-Din al-Tusi, Akhlaq-i Nasiri (1235), tr. G. M. Wickens, The Nasirean Ethics (1964)
Evidence: AI draft
al-Farabi › c. 872–950
Miskawayh
influenced by
Nasir al-Din al-Tusi was asked to translate Miskawayh’s Refinement of Character into Persian and made it the basis of the first, ethical part of his Nasirean Ethics (1235), adding parts on the household and the state. Nasir al-Din al-Tusi, Akhlāq-i Nāṣirī (1235), preface; tr. G. M. Wickens, The Nasirean Ethics (1964)
Evidence: AI draft
Miskawayh › c. 932–1030
Ibn al-Haytham (Alhazen)
influenced by
Al-Tusi’s non-Ptolemaic planetary models in his Memoir on Astronomy (1261), with the “Tusi couple”, belong to the response of the Maragha astronomers to objections against Ptolemy’s models of the kind Ibn al-Haytham had raised in his Doubts; the connection is one of programme rather than direct commentary. G. Saliba, Islamic Science and the Making of the European Renaissance (2007); F. J. Ragep, Nasir al-Din al-Tusi’s Memoir on Astronomy (1993)
Evidence: AI draft
Ibn al-Haytham (Alhazen) › c. 965–1040
Ibn Sina (Avicenna)
influenced by ✓
Al-Tusi’s commentary on Avicenna’s Pointers and Reminders (completed 1246) defended him against Fakhr al-Din al-Razi’s objections and shaped how later scholars read him. Nasir al-Din al-Tusi, Hall mushkilat al-Isharat (1246); SEP “Ibn Sina [Avicenna]”
Evidence: also in Wikidata · Wikidata
Ibn Sina (Avicenna) › 980–1037
Influenced 5
Qutb al-Din al-Shirazi taught
taught ✓
Qutb al-Din studied Ibn Sina’s Remarks and Admonitions and astronomy with Nasir al-Din al-Tusi at the Maragha observatory from about 1262 and became his best-known student; he gave an account of his education himself. F. J. Ragep, “Shīrāzī”, Biographical Encyclopedia of Astronomers (2007); J. Walbridge, The Science of Mystic Lights (1992), ch. 1
Evidence: also in Wikidata · Wikidata
Qutb al-Din al-Shirazi › 1236–1311
al-Sharif al-Jurjani
influenced
Al-Jurjani wrote a commentary on Nasir al-Din al-Tusi’s Memoir on Astronomy (al-Tadhkira fī ʿilm al-hayʾa); the oldest manuscript dates from 1410, during his lifetime. al-Jurjani, Sharḥ al-Tadhkira; F. J. Ragep, Nasir al-Din al-Tusi’s Memoir on Astronomy (1993)
Evidence: AI draft
al-Sharif al-Jurjani › 1340–1413
Jalal al-Din al-Dawani
influenced
Al-Dawani modelled his Jalalian Ethics on al-Tusi’s Nasirean Ethics, and he developed much of his philosophy in glosses on al-Qushji’s commentary on al-Tusi’s Abstract of Theology. TDV İslâm Ansiklopedisi, “Ahlâk-ı Alâî”; R. Pourjavady, in K. El-Rouayheb and S. Schmidtke (eds.), The Oxford Handbook of Islamic Philosophy (2017), ch. 19; SEP “The Liar Paradox in Arabic and Islamic Philosophy”
Evidence: AI draft
Jalal al-Din al-Dawani › c. 1426–1502
Nicolaus Copernicus
influenced disputed ✓
Copernicus used the same construction as the Tusi couple in De revolutionibus (1543); whether he knew al-Tusi’s work, perhaps through Byzantine channels, is disputed. N. Copernicus, De revolutionibus orbium coelestium (1543); F. J. Ragep, “Copernicus and His Islamic Predecessors”, History of Science 45 (2007); G. Saliba, Islamic Science and the Making of the European Renaissance (2007); SEP “Nicolaus Copernicus”
Evidence: also in Wikidata · Wikidata
Nicolaus Copernicus › 1473–1543
Kınalızade Ali Çelebi
influenced
Kınalızade’s Ethics of Ali follows the arrangement of al-Tusi’s Nasirean Ethics – ethics, household, state – which he names among his sources. TDV İslâm Ansiklopedisi, “Ahlâk-ı Alâî” (A. Kahraman); Kınalızade, Ahlâk-ı Alâî (1564), preface
Evidence: AI draft
Kınalızade Ali Çelebi › 1510–1572
Criticism
Criticizes 3
al-Shahrastani
criticised
Al-Tusi answered al-Shahrastani’s attack on Ibn Sina point by point in Wrestler’s Downfall (Maṣāriʿ al-muṣāriʿ), defending Ibn Sina’s metaphysics. Naṣīr al-Dīn al-Ṭūsī, Maṣāriʿ al-muṣāriʿ; Madelung and Mayer 2001
Evidence: AI draft
al-Shahrastani › c. 1086–1153
Fakhr al-Din al-Razi
criticised
Al-Tusi defended Avicenna’s Pointers against al-Razi’s objections (Hall mushkilat al-Isharat) and critically reworked al-Razi’s theology in his Talkhis al-Muhassal. Naṣīr al-Dīn al-Ṭūsī, Ḥall mushkilāt al-Ishārāt; Talkhīṣ al-Muḥaṣṣal
Evidence: AI draft
Fakhr al-Din al-Razi › c. 1150–1210
Athir al-Din al-Abhari
criticised
Nasir al-Din al-Tusi answered al-Abhari’s logic book Tanzīl al-afkār in a systematic critique, Adjusting the Standard (Taʿdīl al-miʿyār), defending Ibn Sina’s logic against al-Abhari’s revisions. al-Tusi, Taʿdīl al-miʿyār fī naqd Tanzīl al-afkār, ed. M. Mohaghegh and T. Izutsu, Collected Texts and Papers on Logic and Language (1974); SEP “al-Khūnajī”
Evidence: AI draft
Athir al-Din al-Abhari › c. 1194–1265
Works
- c. 1235The Nasirean Ethics
Ethics, household management and politics in Persian – for centuries a standard handbook of ethics in the Persian-speaking world.
Position
Al-Tusi was one of the most versatile scholars of the Islamic world. In his commentary on Avicenna’s Remarks and Admonitions he defended Avicenna against the objections of Fakhr al-Din al-Razi and so helped secure his place in later thought. The Nasirean Ethics, written in Persian, combined Miskawayh’s ethics with household management and al-Farabi’s political philosophy, linking individual virtue to the well-ordered community. In theology he laid foundations of Twelver Shiite doctrine. As an astronomer he devised the “Tusi couple”, two circles rolling one inside the other that produce straight-line motion – a construction that later reappears in Copernicus. He also made trigonometry an independent discipline.
Life & context
Nasir al-Din al-Tusi was born in 1201 in Tus in Khorasan and studied there and in Nishapur. For about three decades he served the Ismaili rulers in their mountain fortresses, among them Alamut. When the Mongols took Alamut in 1256 he entered the service of Hülegü, accompanied him to Baghdad in 1258 and persuaded him to build the observatory of Maragha. He died in Baghdad in 1274.
Further main works
- Commentary on Avicenna’s Remarks and Admonitions (mid-13th century)
- Memoir on Astronomy (al-Tadhkira, 1261)
- Ilkhanid Astronomical Tables (Zij-i Ilkhani, 1272)
Appears in
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