
A great mass of literature has been produced to explain and clarify theworks of Aristotle, especially during the ancient and medieval eras. The pupils ofAristotle (384–322 BC) were the first to comment on his writings, a tradition which was continued by thePeripatetic school throughout theHellenistic andRoman periods. TheNeoplatonists of theLater Roman Empire wrote many commentaries on Aristotle, attempting to incorporate him into their philosophy. Although Ancient Greek commentaries are considered the most useful, commentaries continued to be written by the Christian scholars of theByzantine Empire and by the manyIslamic philosophers and Westernscholastics who had inherited his texts.
The first pupils of Aristotle commentated on his writings, but often with a view to expand his work. ThusTheophrastus invented five moods ofsyllogism in the first figure, in addition to the four invented by Aristotle, and stated with additional accuracy the rules ofhypothetical syllogisms. He also often differed with his master,[1] including in collecting much information concerning animals and natural events, which Aristotle had omitted.
During the earlyRoman Empire we find few celebrated names among thePeripatetic philosophers.Nicolaus of Damascus wrote several treatises on the philosophy of Aristotle; andAlexander of Aegae also wrote commentaries on Aristotle.[2] The earliest commentaries which survive, are those written in the 2nd century byAdrastus andAspasius.[3]Alexander of Aphrodisias (c. 200) was regarded by subsequentAristotelians among the Greeks, Latins, and Muslims, as the best interpreter of Aristotle. On account of the number and value of his commentaries, he was called, by way of distinction, "The Commentator". Several of his works are still extant, among which is a treatiseOn Fate, wherein he supports the doctrine ofdivine providence.[2]
Many of theNeoplatonists undertook to explain and illustrate the writings of Aristotle, particularly on the subject ofdialectics, whichPlato had left imperfect.[2]Porphyry (3rd century) wrote a book on theCategories, which was found to be so suitable a complement to theCategories of Aristotle, that it was usually prefixed to that treatise.[1] Porphyry sought to show that Plato and Aristotle were in harmony with each other, especially in regards to the compatibility of Aristotle's Categories with Plato'sTheory of Forms.[3] Porphyry's pupilIamblichus continued this process of harmonising Plato and Aristotle, andDexippus, a disciple ofIamblichus, wrote aReply to the Objections of Plotinus against Aristotle's Categories, which is still extant.Themistius (4th century), who taught atConstantinople with great success, paraphrased several of the works of Aristotle, particularly thePosterior Analytics, thePhysics, and the bookOn the Soul. In the 5th century,Ammonius Hermiae represented Plato and Aristotle in agreeing that god was the artificier of a beginningless universe.[3]Olympiodorus, an Alexandrian philosopher, wrote commentaries upon Aristotle'sMeteorology andCategories.[2]Simplicius of Cilicia (6th century) wrote extensive commentaries upon Aristotle, and, like many of the other Neoplatonists, attempted to reconcile the doctrines of thePythagoreans, of theEleatics, of Plato, and of theStoics, with those of Aristotle.[1] He also strenuously defended Aristotle's doctrine concerning theeternity of the world.[2]
In the 6th century,Boethius entertained the design of translating intoLatin the whole of Aristotle's and Plato's works and of showing their agreement—a gigantic plan, which he never executed.[1] Alongside theCategoriae Decem misattributed toSt Augustine, hisLatin translations and commentaries on Aristotle'sCategories andOn Interpretation andPorphyry'sIsagoge became thelogica vetus ("old logic") through which Aristotle was almost exclusively known in Western Europe until the 1130s.[4] Boethius's near contemporaryJohn Philoponus, however, maintained that Aristotle had been entirely misunderstood by Porphyry and Proclus's incorporation of his terms into Neoplatonism and by projects like Boethius's that sought to reconcile Aristotle with Plato'stheory of forms; John instead offered a Christian interpretation of the Aristotelian corpus.[1] Others, again, wrote epitomes, compounds, abstracts; and tried to throw the works of Aristotle into some simpler and more obviously regular form, asJohn of Damascus, in the middle of the 8th century, who made abstracts of some of Aristotle's works, and introduced the study of the author into theological education. John of Damascus lived under the patronage of the Arabs, and was at first secretary to theCaliph, but afterwards withdrew to amonastery.[1]

The line of the Aristotelian commentators was continued to the later ages of theByzantine Empire. In the 12th centuryAnna Comnena organised a group of scholars which included the commentatorsMichael of Ephesus,[3] andEustratius of Nicaea who employed himself upon the dialectic and moral treatises, and whom she does not hesitate to elevate above the Stoics and Platonists for his talent in philosophical discussions.[1]Nicephorus Blemmydes wrote logical and physical epitomes for the use ofJohn III Doukas Vatatzes;George Pachymeres composed an epitome of the philosophy of Aristotle, and a compendium of his logic:Theodore Metochites, who was famous in his time for his eloquence and his learning, has left a paraphrase of the books of Aristotle onPhysics,On the Soul,On the Heavens, etc.[1] The same period saw the commentaries and paraphrases ofSophonias. In the post-Byzantine period, one of the most important Aristotelian commentators isTheophilos Corydalleus.
One Byzantine-era commentator,Allīnūs, is known only from citations and excerpts in Arabic sources.[5]
In the 9th century, the Platonising school ofThābit ibn Qurra inBaghdad translated Aristotle and his commentators into Arabic.[3] Islamic scholars made a point of studying the writings of Aristotle, especially hismetaphysical and logical writings, and also of hisPhysics. They wrote commentaries on Aristotle, and developed still further the abstract logical element. Many of these commentaries are still extant.[6]
Al-Kindi, who wrote a commentary on Aristotelian logic, lived in the 9th century, underAl-Ma'mun.Al-Farabi (10th century) wrote commentaries on Aristotle'sOrganon, which were made diligent use of by theScholastics. It is related of him that he read through Aristotle's treatiseOn Hearing forty times, and hisRhetoric two hundred times, without getting at all tired of them.[6] The physicians made a study of philosophy, and formulated theories; among them wasAvicenna (c. 980-1037), who came fromBukhara, to the east of theCaspian Sea; he wrote a commentary on Aristotle.Al-Ghazali (1058–1111) wrote compendiums of logic and metaphysics.Averroes (1126–1198), sometimes referred to simply as 'The Commentator', was especially distinguished as a commentator of Aristotle.[6] He often wrote two or three different commentaries on the same work, and some 38 commentaries by Averroes on the works of Aristotle have been identified.[7] Although his writings had only marginal impact in Islamic countries, his works had a huge impact in theLatin West following theLatin translations of the 12th and 13th centuries.[7]
Scholastic philosophy in the Latin West was decisively shaped when the works of Aristotle became widely available, at first through translations of commentators and their basis texts from Arabic, and later through translations from Greek of Aristotle's original text (notably byWilliam of Moerbeke) and of the Greek commentators.Albertus Magnus,Thomas Aquinas,Duns Scotus, andWilliam of Ockham, among many others, wrote important philosophical works in the form of Aristotelian commentaries. On this basis, 14th -century scholarNicole Oresme translated Aristotle's moral works into French and wrote extensivecomments on them.
A list of Medieval and Renaissance commentaries on all of Aristotle's works has been compiled by Charles H. Lohr:[8]
The articles are reprinted in the following volumes by Charles H. Lohr: