Encyclopedia of Philosophy: Alexander of Aphrodisias

« Alexander of Aphrodisias (fl.

c.

AD 200) The Peripatetic philosopher Alexander was known to posterity as the commentator on Aristotle, until Averroes took over this title.

His commentaries eclipsed most of those of his predecessors, which now survive only in scattered quotations.

Used by Plotinus, Alexander's commentaries were the basis for subsequent work on Aristotle by Neoplatonist commentators, and even though some themselves survive only in quotations by these later writers, Alexander's interpretations of particular passages are still helpful and are cited by commentators today.

In addition to Alexander's commentaries we have a number of monographs, and also collections of short discussions which are connected with themes in his writings, though some are probably by pupils rather than by Alexander himself.

Alexander's most influential and controversial doctrine has been his interpretation of Aristotle's theory of soul and intellect; regarding the soul as the product of the mixture of the bodily elements, he has been seen as subordinating form to matter and as thereby misinterpreting Aristotle. Certainly his view excludes any immortality for individuals, but even if Aristotle himself allowed this it is arguable that to do so was incompatible with his definition of soul as the form of potentially living body.

Alexander himself interpreted Aristotle's 'active intellect' not as an immortal element in each individual, but as god, the unmoved mover, apprehended by our own intellects.

Both on the question of soul and on that of the status of universals, Alexander gives a non-Platonizing reading of Aristotle, which accounts for some of the criticism to which he has been subjected by successors both ancient and modern.

His treatment of the problem of free will has also been influential, though his criticisms of determinism are more telling than his own positive solution.

Seeing his task as interpreting Aristotle's writings with the aid of one another and explaining apparent inconsistencies, Alexander contributed to the growth of Aristotelianism as a system; he does not criticize nor challenge Aristotle, and regards his own innovations as Aristotelian doctrine, developed in the context of new questions which Aristotle himself had not confronted in the same form.

He was better at seeing the details than at comprehending the global picture, and the potential of some of his doctrinal contributions is most apparent in what they suggested to others; but there is still much to interest philosophers in his detailed argumentation on particular points and passages.

1 Life, works and relation to Aristotle Alexander's treatise On Fate is dedicated - with some elaborate rhetorical flourishes, and a request to consult him if further clarification is needed - to the emperors Septimius Severus and Caracalla, in gratitude for his appointment as a publicly recognized teacher of Aristotelian philosophy.

Since Caracalla was made Augustus as Septimius Severus' colleague in AD 198, and Geta joined them as a third Augustus in AD 209, the date is fixed as between these two points; but we do not know at what stage in Alexander's career the appointment was made.

Nor do we know for certain where the post in question was, though it is likely enough that it was the chair at Athens established by Marcus Aurelius (§1) in 176; Alexander's use of Aristotle's statue in Athens as an example in On Aristotle's Metaphysics (415.29-31) has been seen as supporting this.

Some of the general characteristics of Alexander's writings have been indicated above.

His surviving commentaries are those on Metaphysics I-V (that on the remainder of the Metaphysics, like that on the Sophistical Refutations, is not by Alexander but by the twelfth-century Michael of Ephesus), Prior Analytics I, the Topics, the Meteorology and On Sensation.

They are characterized by the frequent inclusion of alternative explanations, and by an absence of the formal organization, reflecting the programme of teaching in a school context, that is found in the later Neoplatonic commentaries on Aristotle.

Alexander also wrote commentaries, now known only from later quotations, on the other logical and physical works of Aristotle.

Whether he produced a full-scale commentary on the Ethics is debated, and he shows little or no interest in the zoological, political and rhetorical works.

Alexander's monographs include, surviving in Greek, On the Soul (as distinct from his commentary, now lost, on Aristotle's On the Soul), On Fate, On Mixture, and, surviving only in Arabic translation, On the Principles of the Universe (the authenticity of which has been questioned), On Providence, a work on differentiae, and Refutation of Galen's Attack on Aristotle's Doctrine That Everything That Moves is Set In Motion by a Mover (the actual connection of this treatise with Galen's views, like much else in the Arabic tradition concerning the relations between Alexander and Galen, is doubtful).

There were other monographs, now lost.

In addition, the extant collections of short discussions include, in Greek, the socalled second book of Alexander's On the Soul, better known by the name Mantissa or 'makeweight' given it by its modern editor, Ivo Bruns; three books of Quaestiones (School-Puzzles and Solutions Concerning Nature); and one book of Ethical Problems.

(Another collection, of Medical Puzzles and Physical Problems, has nothing to do with Alexander.) These collections were put together, often ineptly, by editors later than Alexander himself.

Other similar material has been preserved in compendia in Greek manuscripts or in Arabic translation.

Study of the relative dating of Alexander's works, and on the relation between the commentaries and the short discussions, is still in its infancy. Both the relationships among Alexander's works and his loyalty to Aristotle can be illustrated by two particular topics.

Both in the Prior Analytics commentary and in a separate monograph, now lost, Alexander discussed Aristotle's modal logic; Alexander's writings are a major source for the controversy between Aristotle himself and his immediate followers, Theophrastus (§2) and Eudemus, over the conversion of contingent premises and the modality of the conclusions of syllogisms with 'mixed' premises (for example, one necessary and one assertoric).

However, while many would hold that there is more logical elegance in Theophrastus' and Eudemus' view that the conclusion is in every case only as strong as the weakest premise (the medieval rule peiorem semper conclusio sequitur partem) Alexander remains loyal to Aristotle (On Aristotle's Prior Analytics 125.3-127.16).

Second, Alexander answers Aristotle's problem in Physics VIII 4 254b33-, 'What is it that causes the natural movement of a falling heavy body?', by an analogy between the soul, as the form of a living creature and cause of its movement, and heaviness, as the form of a heavy body and the internal cause of its movement.

This analogy - and it is presented only as an analogy - is put forward not only in the Refutation of Galen on Motion, but also in On the Soul (22.7-) and On the Principles of the Universe; and it has been seen by Pines (1961) as a possible ancestor of Philoponus' explanation of the motion of a projectile forced - in Aristotelian terms, rather than natural - by an internal impetus imparted to it by the thrower.

Alexander, as quoted by Simplicius, On Aristotle's Physics 1346.37-, remains loyal to Aristotle's implausible explanation of the continued motion of a projectile by movement imparted to the air behind the projectile as well as to it.

2 Soul and intellect Aristotle defines soul as the first actuality of a natural body potentially. »