In the ninth-century alleys of Baghdad, philosophy did not arrive with a fanfare; it crept in with crates of books. Scribes bent over lamps, copied Greek lines into Syriac, then Syriac into Arabic, their pens scratching like crickets. Under the ʿAbbāsids—al-Maʾmūn most famously—institutions such as the Bayt al-Ḥikma (بيت الحكمة) paid translators like Ḥunayn ibn Isḥāq and Thābit ibn Qurra to chase down Aristotle’s Organon (See: Logic in the Medieval World: Aristotle’s Legacy in Arabic), Theophrastus’s logical treatises, Galen’s medicine, and Plotinus disguised as the “Theology of Aristotle.” These weren’t mere imports. They were refitted. Glosses thickened the margins; examples shifted from Athenian lawcourts to Basran markets; unfamiliar terms were hammered into Arabic: wujūd (وجود) for being, māhiyya (ماهية) for essence, hayūlā (هيولى) and ṣūra (صورة) for matter and form. Paper—new to the region—let the whole endeavor accelerate. Pause, and picture the chain: a book ferried along caravan routes, a translator arguing with his patron over a single verb, a teacher in Kūfa testing a definition on restless students. Philosophy, quite literally, walked into the Islamic world page by page.
Origins and Formation of the Mashshaʾī School
Al-Kindī, later called “the philosopher of the Arabs,” gave this incoming archive a local address. He wrote brisk epistles that stitched Greek doctrines to Qurʾānic concerns—on the First Truth, on the intellect (ʿaql عقل), on cosmic order—and he argued that truth should be taken from wherever it is found, even from people far away in place and language. He did not merely borrow; he sorted and trimmed. Logic became an instrument for clarity rather than an end in itself; metaphysics was tasked with safeguarding divine unity; astronomy and arithmetic were disciplined into a curriculum. Al-Kindī’s circle minted a technical Arabic that could carry Aristotle without breaking Islamic grammar of thought. In his hands, the Peripatetic habit of step-by-step argument—walking from premise to conclusion—began to feel at home in Arabic prose (and in the courts that commissioned it).
Al-Fārābī then built a larger architecture. Reading Aristotle beside Plato,
he drafted a harmony rather than a rivalry: the First Cause stands as the
Necessary, from which intellects emanate in a descending order, each linked
to a celestial sphere, until the Active Intellect sheds light on human
minds. He arranged the sciences like rooms in a well-planned house—logic at
the door, physics and mathematics along the hall, metaphysics at the inner
chamber, politics and ethics opening onto the city. In the Virtuous City,
prophetic law and philosophical insight meet not by accident but by design,
as symbols and syllogisms converge on the same order. With this synthesis,
the Mashshaʾī identity took on a crisp profile: a disciplined method (burhān
برهان), a metaphysics of wujūd and māhiyya, an ethics and political theory
attentive to the formation of character and community. The school did not
merely inherit Aristotle; it refashioned him into a tradition that could
teach, govern, and—when pressed—defend itself.
Doctrines and Method of the Peripatetics
The Peripatetic method begins with a discipline of steps. Logic polishes language until it can carry proof; terms are fixed, ambiguities pared away, and premises weighed for certainty. Demonstration (burhān) is not debate for the sake of winning but a carefully jointed structure: from true, primary principles to necessary conclusions, like stones keyed into an arch. Dialectic tests opinions; rhetoric guides citizens; poetics moves the imagination; but demonstration alone yields science. From this measure of certainty, the sciences are sorted and stacked. Theoretical disciplines—physics, mathematics, metaphysics—seek what is; practical ones—ethics, household management, politics—shape what ought to be; productive arts—crafts, poetics—make what did not exist before. The Organon is the toolbench: definition (ḥadd حد) sets the form, division (qisma قسمة) clears the field, syllogism (qiyās قياس) drives the argument forward, and sophistical refutations sweep away glittering errors. The result is a way of walking: step, step, step—no leaps, no shortcuts (and no pretended certainty where none can be had).
Metaphysics takes that method to the highest questions. The key distinction is between being (wujūd) and essence (māhiyya): what a thing is can be stated without knowing that it exists, and existence “joins” essence in contingent beings. From this hinge, Ibn Sīnā (ابن سينا) argues that contingent things, taken as a whole, cannot explain themselves; the chain of borrowed existence cannot be infinite in the relevant way. There must be a Necessary Existent (wājib al-wujūd واجب الوجود) whose essence is to be, simple and without parts, the source on which all other beings depend. The cosmos then unfolds in a graded order: from the First emanate intellects; each intellect is paired with a celestial sphere; at the edge of the sublunar world the Active Intellect gives form to matter and light to human understanding. Causes are not only pushes in time; they are formal, final, and intelligible reasons that make things what they are. Categories sort substance from accidents; potentiality ripens into actuality; time measures motion as a shadow measures walking. The metaphysician does not merely announce that God exists; he trims each concept, tests each link, and lets an ordered universe come into view.
Epistemology and psychology then show how human minds fit this order. The
soul (nafs نفس) is the form of a living body, layered by powers: nutritive,
sensitive, imaginative, rational. Sense grasps particulars; imagination
rearranges them like a painter moving cutouts on a board; the intellect
(ʿaql) abstracts the universal form. It passes through stages: potential
intellect (able but unlit), actual intellect (grasping a form), acquired
intellect (stably possessed), all aided by the Active Intellect (al-ʿaql
al-faʿʿāl العقل الفعال) that shines like a lamp held just behind the eye.
Ibn Sīnā’s thought experiment—imagine yourself suspended, blindfolded, cut
off from touch—suggests that the self would still affirm its own being; the
rational soul is not identical with any bodily organ. From here, prophecy
becomes thinkable without dissolving into marvels: a perfected imagination,
joined to the Active Intellect, can receive forms swiftly and cast them into
images, laws, and stories a community can live by. Thus philosophy and
religion are not enemies but two registers of one truth. Ibn Rushd will
later codify the rule: when demonstration establishes a result, revealed
texts—where they seem to clash—invite interpretation (taʾwīl تأويل) for the
learned, while their plain sense guides the many. Different audiences,
different paths, one sun.
The Long Walk West: Avicenna, Averroes, and the Afterlives of Mashshaʾiyya
With Ibn Sīnā, the Mashshaʾī project settled into ḥikma ilāhiyya (حكمة إلاهية)—philosophical theology (See: Philosophy and Theology: Friends or Rivals in the Middle Ages?)with a clear map and sturdy joints. He arranged his encyclopedias like a city plan: logic as gate, physics and mathematics along the main avenue, metaphysics at the inner court where the Necessary Existent is examined with the same care a jeweler gives a flawed gem. The distinction of essence and existence, the chain of emanating intellects, the psychology of the rational soul, the re-reading of prophecy—each was placed, tested, and then taught. His works moved across desks and decades: al-Shifāʾ and al-Najāt for the schoolroom, al-Ishārāt wa-l-Tanbīhāt for the adept, short essays for patrons in a hurry. Commentators began to orbit him. Fakhr al-Dīn al-Rāzī poked and prodded; Naṣīr al-Dīn al-Ṭūsī patched and defended. Even dissent used Avicennian grammar. What emerged was not a mirror of Aristotle but a self-standing architecture in Arabic and Persian that could house theological questions without collapsing under them (and a patient pedagogy for guiding students from definition to demonstration).
In al-Andalus, Ibn Rushd (ابن رشد) tried a different repair: he scraped away the gloss to recover Aristotle’s original grain. As qāḍī and court physician, he wrote in bursts—Short, Middle, and Long Commentaries—filling folios with meticulous paraphrase, line-by-line exegesis, and sharp corrections where earlier readers had drifted. He argued that philosophy is not optional ornament but a duty for the qualified: the Decisive Treatise (Faṣl al-Maqāl فصل المقال) sets out the rule that demonstrative conclusions govern interpretation, not the other way around. Faced with al-Ghazālī’s Incoherence of the Philosophers, he replied with the Incoherence of the Incoherence, insisting that eternity, causality, and the intellect can be reasoned through without impiety. He sorted audiences as carefully as he sorted arguments—rhetoric for the many, dialectic for theologians, demonstration for philosophers—so that one law could serve multiple paths. His revival did not erase Ibn Sīnā; it offered a counterweight, a reminder that the Peripatetic walk should keep pace with Aristotle’s steps.
From Iberia and Sicily, the books crossed into Latin Christendom on the
backs of mules and in the hands of translators. At Toledo and Palermo, teams
clustered around lecterns: Gerard of Cremona chasing clear Latin for
Avicenna’s metaphysics (the Liber de philosophia prima) and psychology (De
anima), Michael Scot tackling Ibn Rushd’s commentaries, Dominicus
Gundissalinus bridging technical terms. In Paris and Cologne, Albertus
Magnus and Thomas Aquinas read, excerpted, and argued. Aquinas adopted and
recast the essence–existence distinction; his “Third Way” bears the mark of
Avicenna’s contingency proof. Latin Averroists tested Ibn Rushd’s unity of
the intellect and ran into condemnations in 1270 and 1277. Meanwhile, in the
Islamic East, the story did not end but bent. Al-Ghazālī’s critique narrowed
philosophy’s public authority, yet Avicennian structures endured inside
kalām and in the madrasa curriculum. Shihāb al-Dīn al-Suhrawardī proposed
Illuminationism (Ishrāq), adding knowledge by presence (ʿilm ḥuḍūrī) and a
metaphysics of light; later, Safavid thinkers such as Mīr Dāmād and Mullā
Ṣadrā fused Avicennian analysis with Illuminationist and Sufi insights,
arguing for the primacy of existence (aṣālat al-wujūd) and even substantial
motion. The Mashshaʾī spirit—methodical, metaphysical, confident that reason
and revelation can share a table—continued to migrate, from Persian
seminaries to Ottoman and Mughal classrooms, and into the wider history of
philosophy where its problems and proofs still set the pace.
Where Reason and Revelation Share a Wall
From Aristotle’s courtyard, where students literally walked while thinking, to Baghdad’s scriptoria where pens scratched and translators ferried meanings across languages, Peripatetic philosophy entered Islam, was refitted by al-Kindī and al-Fārābī, systematized by Ibn Sīnā, and pared back to Aristotle’s grain by Ibn Rushd. What began as Greek tools—logic, demonstration, categories—was hammered into an Arabic idiom and then shelved in curricula, cited in legal debates, carried west to Paris, and criticized, defended, and transformed.
The thread that holds this tapestry is simple (and demanding): rational inquiry and metaphysical contemplation can live with faith, not as rivals but as neighbors who share a wall—burhān weighing premises while waḥy guides communities through symbol and law, taʾwīl bending the text when demonstration compels it. This is not antiquarian display. It reaches into today’s seminar rooms and interreligious panels, where we still ask how to read scripture without dimming intellect, how to speak of the soul in an age of neuroscience, how to think causality without choking on mechanism. The Mashshaʾī legacy offers a stance rather than a slogan: move step by step, name your terms, test your reasons, and let revelation and reason meet in daylight. The walk that began in the Lyceum did not stop in Baghdad or Cordoba—it turns a corner and keeps going.
For more insight:
- Gutas, Dimitri. Greek Thought, Arabic Culture: The Graeco-Arabic Translation Movement in Baghdad and Early ʿAbbāsid Society (2nd–4th/8th–10th Centuries). Routledge, 1998.
- The Cambridge Companion to Arabic Philosophy. Edited by Peter Adamson and Richard C. Taylor, Cambridge University Press, 2005.
- The Oxford Handbook of Islamic Philosophy. Edited by Khaled El-Rouayheb and Sabine Schmidtke, Oxford University Press, 2016.
- McGinnis, Jon. Avicenna. Oxford University Press, 2010.
- Mahdi, Muhsin. Alfarabi and the Foundation of Islamic Political Philosophy. University of Chicago Press, 2001.
- Fakhry, Majid. A History of Islamic Philosophy. 3rd ed., Columbia University Press, 2004.