Alexandre de Afrodísias

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 (see below). In addition, the extant collections of short discussions include, in Greek, the so-called 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 (see Alexander, On Aristotle’s Prior Analytics 125.30– 1; Philoponus, On Aristotle’s Prior Analytics 126.20), 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 (see Philoponus §2). 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 possessing life, or, more shortly, of an organic body, and regards the soul of a living creature as its form (see Aristotle §17; Psychē ). But it is controversial how this is to be understood. Some have interpreted Aristotle’s notion of soul as a functionalist one; but this view has been criticized on the grounds that it does not do justice to the close connection in Aristotle between the performance of a given function and the particular arrangement needed for it. This close connection between form and matter in Aristotle’s theory of them has caused major difficulties for interpreters, because it is not clear how soul and body can be logically distinguished, if a lifeless hand or eye is a hand or eye only in name, and only an already living, ’ensouled’ body is to count as an organic body. It seems that either body must be defined in terms of soul, which raises the question whether there is any level at which the matter of a living body is specifiable without reference to its soul, or else that soul must be accounted for in terms of the arrangement of the body and its parts.

Interpreters of Aristotle have favoured the former approach. Aristotle himself (in On the Soul I 4) rejects – though with some hesitation – the notion that soul can be a ‘harmony’ or arrangement of the bodily elements, partly because such an arrangement cannot itself be a cause of movement as the soul is. However, Alexander not only defines the soul as the product of the mixture of the bodily elements ( On the Soul 24.21–3), apparently following Andronicus, but sets out his exposition of the nature of soul by starting with the simple bodies, earth, air, fire and water, and working upwards through progressively more elaborate compounds until he arrives at living creatures and finally at human beings. It is therefore hardly surprising that his account of the soul has often been criticized as materialist, reductivist and un-Aristotelian. However, these criticisms may to some extent reflect the critics’ own standpoints, and their own interpretations of Aristotle. It is scarcely un-Aristotelian to suggest that a given form requires a given arrangement of given types of matter, and Alexander’s order of exposition need not indicate that he regards more complex forms as posterior to less complex ones so far as explanatory or ontological dependence is concerned. Indeed he derives the substantiality of the form–matter composite from that of the form and the matter (6.2–4), and insists that it is the form of each thing that determines its nature (7.4–8). Moreover, texts attributed to Alexander insist that form is not in matter, or soul in body, in the way that a quality can be in a substrate, because it is by the form and the soul that the matter and the body are characterized in the first place (Quaestiones I 8, 17, 26; Mantissa 119–22.)

It is true that Alexander’s treatment of soul excludes any individual immortality; indeed this was his chief source of popularity in the Renaissance (see §5). But Aristotle’s view itself arguably encounters difficulties where personal immortality is concerned. Attribution to Aristotle, in his mature period, of belief in personal immortality turns on interpretation of his remarks concerning intellect, and especially the so-called ’active intellect’ of his own On the Soul III.5 (see Aristotle §19; Nous). Alexander, however, identifies the active intellect not with an element peculiar to the soul of each individual but with god, the ’unmoved mover’ of Metaphysics XII. The theory of intellect is discussed both in Alexander’s On the Soul and in a section of the Mantissa which is of doubtful authenticity and seems itself to be a combination of several different texts, but which circulated independently in the Middle Ages first in Arabic translation and then in Latin, and was more influential than Alexander’s On the Soul itself. Common to both works is the view that the individual human’s intellect at birth is purely potential; it is therefore referred to as ’material intellect’, by analogy with the potentiality of matter in the ordinary sense of the latter term. Since, however, it must be receptive to all forms, it has no nature of its own (see Aristotle, On the Soul III 4, 429b10–22); and indeed in On the Soul its state at birth is likened not so much to a blank writing-tablet (Aristotle, On the Soul III 4, 429a31–) as to the blankness of the tablet (84.24–7). As a person grows to adulthood the ’material’ intellect develops, by the acquisition of concepts through the abstraction of matter from the forms in substances composed of form and matter, until it becomes intellect ’in disposition’ (en hexei, later Latinized as in habitu), capable of independent thought.

What is less clear is the part which the active intellect is supposed to play in this process. Alexander’s On the Soul, characteristically, simply presents two arguments that the unmoved mover, as pure self-thinking intellect and intelligible in its own right, is responsible for our thinking too, without explaining very adequately how this comes about. First, as supremely intelligible it must be the cause of other things’ intelligibility (88.24–89.8) – an argument which sounds more Platonist than Aristotelian, though it is not indeed being used here to establish the existence of intelligible pure form. And second, it is the cause of being for all other things, and thus for all the objects of intellect (89.9–19). This is probably to be understood in terms of the movement of the heavens, caused by the unmoved mover, being the cause of sublunary coming-to-be (see §4); but as an explanation of how our intellects become able to think it scarcely seems adequate. In the short text On Intellect (107.31–4, 108.19–22), on the other hand, the active intellect appears to act directly upon our intellect, apparently by providing it with a paradigm of pure form and thus enabling it to separate other, ‘enmattered’ forms from the matter in which they are embodied – which apparently has the rather implausible implication that we must apprehend god, in order to possess this paradigm, before we can think of anything else in general terms. In On the Soul 90.11– 20 it is argued that, since intellect is identical with its object at any given time, immortality can be present in us when we think of god; but it is not our own ’material’ intellect that then becomes immortal. This is the only immortality open to us as individuals (but see below on the eternity of species).

On Intellect (whether itself by Alexander or not) indicates that Alexander’s treatment of the topic built upon earlier Peripatetic discussions, and that the identification of the active intellect with god rather than with an element in the individual soul had already been connected with Aristotle’s reference to ’intellect from outside’ (Generation of Animals II 3 736b27–). But that in fact relates to the origin of intellect in the context of the generation of individual human beings, with no explicit identification of the source from which such intellect comes, and no apparent reference to its entering into us through acts of intellectual apprehension, as in Alexander’s view.

3 Universals

Aristotle rejects the Platonist view that forms of material objects can exist even in the absence of any material instances, and holds that the form of human being exists only in individual human beings and, in a different way, in the minds that think of them. What is much less clear is Aristotle’s view of the ontological status of such forms, and in particular whether they are to be regarded as individual or universal. Alexander regards universals as posterior to individuals. He has therefore been criticized for adopting an un-Aristotelian nominalism; but his position is in fact more subtle. If we accept the evidence of the Quaestiones (I 3), Alexander draws a distinction between the nature, as such, of a species, and that nature as a universal. Definition is of what is common to the members of a species, as opposed to the individual accidents due to matter ( On the Soul 85.15–18, where Alexander seems to adopt a doctrine of numerically distinct forms in different members of the same species; see Aristotle). But the definition of the nature of the species would still be the same even if only one member of the species existed. Definition is thus of what is common, but not of what is common as common, and it is purely accidental to a specific nature whether it is universal, in the sense of having more than one instantiation, or not. However, while the individual is prior to the universal in the sense that an individual can exist without there being a universal, the universal is none the less, in cases where there is more than one instance, prior to any particular individual; the existence of ’human being’ does not depend on the existence of Socrates or of any other particular named individual ( On Providence, Ruland 1976: 89; compare Alexander reported by Dexippus, On Aristotle’s Categories 45.16 and by Simplicius, On Aristotle’s Physics 19.5–11). Similarly, the genus is prior to the species (Quaestiones I 11–). There can be animals without there being horses, but not horses without there being animals; on the other hand, this horse would still be an animal even if there were no other animals and no other horses at all.

Alexander does say ( On the Soul 90.2–11) that forms embodied in matter depend for their existence on being intelligized, and that (Quaestiones II 28 78.18–20) genus as genus – that is, as including several different species – is just a name, its existence depending on its being thought of. But it is not clear that this involves nominalism, if by nominalism is meant the view that common natures are arbitrary thought-constructs or that their reality derives purely from our giving a common name to a particular collection of individuals (see Nominalism). The point of the statement at On the Soul 90.2–11 is to contrast them with pure intelligible forms (the unmoved movers), and, given the part played by specific natures in Alexander’s theory of providence (see §4), it seems that, far from being nominalist, Alexander’s theory of species is essentialist, involving a rigid distinction between the nature common to the species and individual accidents.

4 Providence and fate

On both providence and fate Alexander adapts Aristotelian materials to the discussion of new issues, presenting the resulting account as ’Aristotelian’. In the case of providence, discussed in the treatise On Providence and in several of the Quaestiones, especially the unfinished dialogue II 21, he is concerned to mediate between, on the one hand, interpretations of Aristotle (especially but not only by the hostile Platonist Atticus) as making divine influence on the sublunary world purely accidental and so not providence at all, and, on the other hand, the pantheistic doctrine of the Stoics (see Stoicism §5), which he regards as unworthy of the divine dignity by involving god directly in every detail of the world, however humble, and also as incompatible with the perceived existence of evils. His solution makes use of the Aristotelian theory (Generation and Corruption II 10) that the motion of the heavens and especially of the sun on the ecliptic, caused by desire for the unmoved mover, is responsible for the cycle of the seasons and thus for the continuity of coming-to-be and passing-away and the perpetuation of natural kinds. Alexander interprets this as providence, but a providence concerned with the eternity of species rather than with the fortunes of individuals. The charge that providence involves the divine existing for the sake of what is inferior to it was apparently answered by the argument (Quaestiones I 23 36.22–3; compare with I 25 41.1–2; On the Principles of the Universe, Badawi 1968: 127–8) that the continuation of the sublunary world benefits the heavens by giving them a centre around which to revolve; and Alexander apparently accepted that non-accidental providence must involve some awareness of its objects on the part of what exercises it, the divine presumably being aware of sublunary beings as species but not as individuals. Some of the details remain obscure, especially as concerns the identity of the being or beings exercising providence and the relation here between the divine heavenly spheres on the one hand and the unmoved mover(s) on the other; moreover, Alexander’s theory of providence amounts to little more than an upholding of the general ordering of the world, as opposed to the concern with its complex history, and especially with the fortunes of individual human beings, characteristic of both the Stoic and the Judaeo-Christian traditions. At the end of the twelfth century Alexander’s treatise On Providence was used as a source for ancient Greek theories – and its denial of divine concern for individuals rejected – by Moses Maimonides (Guide to the Perplexed III 16–17).

The notion of a general ordering of the universe which is unaffected by variations in detail also appears in Alexander’s treatise On Fate (ch. 25), where it is used to counter the argument (Stoic, though the determinists attacked in the treatise are never actually named there as Stoics) that a nexus of causes and effects admitting of no exceptions is essential if the unity of the universe is to be preserved (see Stoicism §20). Unfortunately – and characteristically – Alexander in this treatise is more concerned to attack the determinist account of human agency, as conflicting with common experience and detrimental to morality, than to explain how in his own view human agency fits into the world as a whole; this problem is more pressing for him than for Aristotle, because he is concerned to reject determinism while also claiming to avoid the introduction of any ’uncaused motion’. There is a similarity between Alexander’s philosophical position here and the way in which Carneades had sought to escape determinism while rejecting the Epicureans’ uncaused atomic ’swerve’ (see Epicureanism §§4, 12; Carneades §3; and further below), though the question of possible historical influence of Carneades on Alexander is undecided, and Alexander makes no explicit reference to the atomic swerve or to the problems it involves. An attempt to locate human agency in the context of a general worldview is made by one of the short texts attributed to Alexander ( Mantissa , Bruns 1887–92: 169–172), which thus reveals the limitations of Alexander’s own treatment. However, by linking responsible choice to uncaused motion, contrary to Alexander’s own view, it succeeds only in demonstrating the difficulties of a radical indeterminism.

In the absence of any single and systematic account of exceptions to determinism in On Fate , we are left with a series of separate claims:

(1) Alexander begins by setting out (chaps 3–6) an anti-determinist doctrine of fate – perhaps taken over, indeed, from earlier Peripatetic sources, basing it on the Aristotelian doctrine of nature as what applies for the most part but not always. Our actions are for the most part in accordance with our individual character, but not inevitably so.

(2) The occurrence of chance events disproves determinism (ch. 8; compare ch. 24). The stock Aristotelian examples of coincidences (finding buried treasure, and the like) which Alexander uses can, however, be accommodated within the Stoic system; true, if everything that happens is part of a single providential plan they will not really be coincidences, but Alexander’s claim that they are rests, like much of his anti-Stoic argumentation in On Fate , on appeals to a common opinion which turns out to be Aristotelian school doctrine.

(3) Alexander argues (ch. 15) that our action can be free from being predetermined, and yet not be uncaused, because we ourselves, as agents, are the cause, this indeed being what it means to be human. This argument resembles, in general character though not in the details of its expression, that of Carneades on the same issue (Cicero, On Fate 25) which Richard Taylor has seen as anticipating modern agent causation theory. It is not, however, clear that introducing non-physical causes can provide a way out of the dilemma that either everything that occurs is predetermined on the physical level, or else there must be some break in the continuity of such physical causation.

(4) Following Aristotle (Nicomachean Ethics III 5), Alexander argues (chaps 27–9) that even if an agent cannot act contrary to a developed character, the development of that character is itself the agent’s responsibility. This argument is unsatisfactory in itself – as Alexander apparently realizes; see (5) – simply pushing the problem back into the past; it also involves a view of the relation between natural endowment, developed character and action which is at least on the face of it different from that in (1). (Other texts attributed to Alexander take up this point, reconciling the two approaches by arguing that, while innate proclivities vary, everyone who is not morally deformed has the capacity to become virtuous: Mantissa 175.25–32; Ethical Problems 161.15–29.)

(5) To meet the difficulty of reconciling responsible choice, understood as requiring that the agent be able (and ’able’ not just in a counterfactual sense) either to perform or not to perform the act in question, with the argument that for any given agent with a given perspective on a given situation only one course of action will be reasonable, Alexander makes three points. First, our actions are aimed not towards one goal but towards three: the noble, the advantageous and the pleasant (ch.15). The identification of these three ends is Aristotelian (Nicomachean Ethics II 3, 1104b30–), but not their treatment as equally valid alternatives for a single individual, and in the context of Alexander’s argument it raises the question of what account we are to give of an agent’s choice between them. Second, there is a certain degree of latitude, more than one possible action expressing a given character-trait or goal (ch. 29). This seems not to capture morally significant choices. Third, we may sometimes act otherwise than we normally would in a given situation, just to prove that we have the capacity to do so, and especially to confound a prophet (ch. 29). (A modern version might put it in terms of confounding a psychologist.) But this is entirely compatible with determinism, the abnormal action itself being a theoretically predictable reaction to an unusual situation.

Although Alexander fails to clarify his position, to such an extent that D. Frede has classified his position as compatibilist rather than libertarian (see Free will §1), the detailed arguments of the treatise On Fate anticipate many of the moves made in the free-will debate subsequently, and show considerable ingenuity. Alexander’s strongest anti-determinist argument rests on the inability of determinism to make sense of our experiences of choice and deliberation; and, in an argument analogous to Pascal’s wager (see Pascal §6 ), he claims (ch. 21) that there is less danger in believing our actions are not predetermined when in fact they are, than in believing that they are when in fact they are not.

5 Influence

Alexander’s commentaries were read in the school of Plotinus, the founder of Neoplatonism (Porphyry, Life of Plotinus 14). Studies of Alexander’s influence on Plotinus have tended to find numerous correspondences in points of detail rather than conclusive evidence of influence on the major features of Plotinus’ system. Plotinus used Alexander essentially as a guide to understanding Aristotle; the way in which Plotinus formulates the Aristotelian principle of the identity of intellect and its object shows Alexander’s influence, but the doctrine itself had been adopted by Platonism earlier. Some have seen a connection between Alexander’s discussion of a plurality of pure forms without matter (the plurality of unmoved movers) and Plotinus’ doctrine of the unity of ’forms in intellect’; but Plotinian, and Platonic, forms are related to sensible objects in a different way from the Aristotelian unmoved movers, and in any case Alexander refers to pure forms sometimes in the singular and sometimes in the plural without seeming to attach much significance to the difference between the two. If Alexander’s remarks did influence the Plotinian theory, they probably did so because of Plotinus’ reflecting upon them rather than because of any awareness by Alexander of their possible significance. Similarly, too, with the suggestion that for Alexander our intellect, by apprehending the divine intellect, also apprehends its eternal objects; such a theory can be seen as a logical extension of Alexander’s views, but it goes beyond anything that he actually says.

This point can be generalized. The limitations of Alexander’s discussion of the active intellect have already been mentioned; his relatively terse reference to our achieving temporary immortality through contemplation of god is probably to be interpreted in terms not so much of mystical experience as of a desire to develop the logical implications of his account. Nevertheless, Alexander’s doctrine of a single suprapersonal active intellect was immensely influential; it was later adopted by Averroes, though he – influenced by Neoplatonism – regarded the ’passive’ or potential intellect too as one for all human beings. Aquinas was therefore able to cite Alexander for the individuality of the passive intellect in his controversy with the Averroists (see Aquinas §7; Averroism §1, 2), even though differing from him concerning the active intellect and the immortality of the individual. In the sixteenth century Alexander’s view, rejecting personal immortality, was advocated notably by Petro Pomponazzi, in successful defiance of the decree of the Lateran Council in 1513 that ’individual immortality could be demonstrated philosophically and consequently had to be defended by all philosophers’ (Kessler 1988: 495, 507), and by Jacopo Zabarella .