Plotinus (204/5 – 270 C.E.), is generally regarded as thefounder of Neoplatonism. He is one of the most influentialphilosophers in antiquity after Plato and Aristotle. The term‘Neoplatonism’ is an invention of early 19^thcentury European scholarship and indicates the penchant of historiansfor dividing ‘periods’ in history. In this case, the termwas intended to indicate that Plotinus initiated a new phase in thedevelopment of the Platonic tradition. What this‘newness’ amounted to, if anything, is controversial,largely because one’s assessment of it depends upon one’sassessment of what Platonism is. In fact, Plotinus (like all hissuccessors) regarded himself simply as a Platonist, that is, as anexpositor and defender of the philosophical position whose greatestexponent was Plato himself. Originality was thus not held as apremium by Plotinus. Nevertheless, Plotinus realized that Platoneeded to be interpreted. In addition, between Plato and himself,Plotinus found roughly 600 years of philosophical writing, much of itreflecting engagement with Plato and the tradition of philosophy heinitiated. Consequently, there were at least two avenues fororiginality open to Plotinus, even if it was not his intention to sayfundamentally new things. The first was in trying to say what Platomeant on the basis of what he wrote or said or what others reportedhim to have said. This was the task of exploring the philosophicalposition that we happen to call ‘Platonism’. The secondwas in defending Plato against those who, Plotinus thought, hadmisunderstood him and therefore unfairly criticized him. Plotinusfound himself, especially as a teacher, taking up these two avenues.His originality must be sought for by following his path.

• 1. Life and Writings
• 2. The Three Fundamental Principles of Plotinus’ Metaphysics
• 3. Human Psychology and Ethics
• 4. Beauty
• 5. Principal Opponents
• 6. Influence
• Bibliography
  • A. Primary Literature
  • B. Secondary Literature
  • C. Reference
• Academic Tools
• Other Internet Resources
• Related Entries

1. Life and Writings

Owing to the unusually fulsome biography by Plotinus’ disciplePorphyry, we know more about Plotinus’ life than we do about mostancient philosophers’. The main facts are these.

Plotinus was born in Lycopolis, Egypt in 204 or 205 C.E. When he was28, a growing interest in philosophy led him to the feet of oneAmmonius Saccas in Alexandria. After ten or eleven years with thisobscure though evidently dominating figure, Plotinus was moved tostudy Persian and Indian philosophy. In order to do so, he attachedhimself to the military expedition of Emperor Gordian III to Persia in243. The expedition was aborted when Gordian was assassinated by histroops. Plotinus thereupon seems to have abandoned his plans, makinghis way to Rome in 245. There he remained until his death in 270 or271.

Porphyry informs us that during the first ten years of his time inRome, Plotinus lectured exclusively on the philosophy of Ammonius.During this time he also wrote nothing. Porphyry tells us that whenhe himself arrived in Rome in 263, the first 21 of Plotinus’ treatiseshad already been written. The remainder of the 54 treatisesconstituting hisEnneads were written in the last seven oreight years of his life.

Porphyry’s biography reveals a man at once otherworldly and deeplypractical. The former is hardly surprising in a philosopher but thelatter deserves to be noted and is impressively indicated by the factthat a number of Plotinus’ acquaintances appointed him as guardian totheir children when they died.

Plotinus’ writings were edited by Porphyry (there was perhaps anotheredition by Plotinus’ physician, Eustochius, though all traces of itare lost). It is to Porphyry that we owe the somewhat artificialdivision of the writings into six groups of nine (hence the nameEnneads from the Greek word for ‘nine’). In fact,there are somewhat fewer than 54 (Porphyry artificially divided someof them into separately numbered ‘treatises’), and theactual number of these is of no significance. The arrangement of thetreatises is also owing to Porphyry and does evince an orderingprinciple.Ennead I contains, roughly, ethical discussions;Enneads II–III contain discussions of natural philosophy andcosmology (though III 4, 5, 7, 8 do not fit into this rubric soeasily);Ennead IV is devoted to matters of psychology;Ennead V, to epistemological matters, especially the intellect;andEnnead VI, to numbers, being in general, and the One aboveintellect, the first principle of all. It is to be emphasized thatthe ordering is Porphyry’s. The actual chronological ordering, whichPorphyry also provides for us, does not correspond at all to theordering in the edition. For example,Ennead I 1 is the53^rd treatise chronologically, one of the last thingsPlotinus wrote.

These works vary in size from a couple of pages to over a hundred.They seem to be occasional writings in the sense that they constitutewritten responses by Plotinus to questions and problems raised in hisregular seminars. Sometimes these questions and problems guide theentire discussion, so that it is sometimes difficult to tell whenPlotinus is writing in his own voice or expressing the views ofsomeone else. Typically, Plotinus would at his seminars have read outpassages from Platonic or Aristotelian commentators, it being assumedthat the members of the seminar were already familiar with the primarytexts. Then a discussion of the text along with the problems itraised occurred.

One must not suppose that the study of Aristotle at these seminarsbelonged to a separate ‘course’ on the great successor ofPlato. After Plotinus, in fact Aristotle was studied on his own aspreparation for studying Plato. But with Plotinus, Aristotle, itseems, was assumed to be himself one of the most effective expositorsof Plato. Studying both Aristotle’s own philosophy as explained bycommentators such as Alexander of Aphrodisias (2^nd –early 3^rd c. C.E.) and his explicit objections to Plato wasa powerful aid in understanding the master’s philosophy. In part,this was owing to the fact that Aristotle was assumed to know Plato’sphilosophy at first hand and to have recorded it, including Plato’s‘unwritten teachings’. In addition, later Greekhistorians of philosophy tell us that Plotinus’ teacher, AmmoniusSaccas, was among those Platonists who assumed that in some senseAristotle’s philosophy was in harmony with Platonism. This harmonydid not preclude disagreements between Aristotle and Plato. Nor didit serve to prevent misunderstandings of Platonism on Aristotle’spart. Nevertheless, Plotinus’ wholesale adoption of many Aristotelianarguments and distinctions will seem less puzzling when we realizethat he took these both as compatible with Platonism and as useful forarticulating the Platonic position, especially in areas in which Platowas himself not explicit.

2. The Three Fundamental Principles of Plotinus’ Metaphysics

The three basic principles of Plotinus’ metaphysics are called by him‘the One’ (or, equivalently, ‘the Good’),Intellect, and Soul (see V 1; V 9.). These principles are bothultimate ontological realities and explanatory principles. Plotinusbelieved that they were recognized by Plato as such, as well as by theentire subsequent Platonic tradition.

The One is the absolutely simple first principle of all. It is both‘self-caused’ and the cause of being for everything elsein the universe. There are, according to Plotinus, various ways ofshowing the necessity of positing such a principle. These are allrooted in the Pre-Socratic philosophical/scientific tradition. Acentral axiom of that tradition was the connecting of explanation withreductionism or the derivation of the complex from the simple. Thatis, ultimate explanations of phenomena and of contingent entities canonly rest in what itself requires no explanation. If what is actuallysought is the explanation for something that is in one way or anothercomplex, what grounds the explanation will be simple relative to theobserved complexity. Thus, what grounds an explanation must bedifferent from the sorts of things explained by it. According to thisline of reasoning,explanantia that are themselves complex,perhaps in some way different from the sort of complexity of theexplananda, will be in need of other types of explanation. Inaddition, a plethora of explanatory principles will themselves be inneed of explanation. Taken to its logical conclusion, the explanatorypath must finally lead to that which is unique and absolutelyuncomplex.

The One is such a principle. Plotinus found it in Plato’sRepublic where it is named ‘the Idea of the Good’and in hisParmenides where it is the subject of a series ofdeductions (137c ff.). The One or the Good, owing to its simplicity,is indescribable directly. We can only grasp it indirectly bydeducing what it is not (see V 3. 14; VI 8; VI 9. 3). Even the names‘One’ and ‘Good’ arefautes de mieux.Therefore, it is wrong to see the One as a principle of oneness orgoodness, in the sense in which these are intelligible attributes.The name ‘One’ is least inappropriate because it bestsuggests absolute simplicity.

If the One is absolutely simple, how can it be the cause of the beingof anything much less the cause of everything? The One is such acause in the sense that it is virtually everything else (see III 8. 1;V 1. 7, 9; V 3. 15, 33; VI 9. 5, 36). This means that it stands toeverything else as, for example, white light stands to the colors ofthe rainbow, or the way in which a properly functioning calculator maybe said to contain all the answers to the questions that can belegitimately put to it. Similarly, an omniscient simple deity may besaid to know virtually all that is knowable. In general, if A isvirtually B, then A is both simpler in its existence than B and ableto produce B.

The causality of the One was frequently explained in antiquity as ananswer to the question, ‘How do we derive a many from theOne?’ Although the answer provided by Plotinus and by otherNeoplatonists is sometimes expressed in the language of‘emanation’, it is very easy to mistake this for what itis not. It is not intended to indicate either a temporal process orthe unpacking or separating of a potentially complex unity. Rather,the derivation was understood in terms of atemporal ontologicaldependence.

The first derivation from the One is Intellect. Intellect is thelocus of the full array of Platonic Forms, those eternal and immutableentities that account for or explain the possibility of intelligiblepredication. Plotinus assumes that without such Forms, there would beno non-arbitrary justification for saying that anything had oneproperty rather than another. Whatever properties things have, theyhave owing to there being Forms whose instances these properties are.But that still leaves us with the very good question of why an eternaland immutable Intellect is necessarily postulated along with theseForms.

The historical answer to this question is in part that Plotinusassumed that he was following Plato who, inTimaeus (30c;cf.Philebus 22c), claimed that the Form of Intelligible Animalwas eternally contemplated by an intellect called ‘theDemiurge’. This contemplation Plotinus interpreted as cognitiveidentity, since if the Demiurge were contemplating something outsideof itself, what would be inside of itself would be only an image orrepresentation of eternal reality (see V 5) – and so, it would notactually know what it contemplates, as that is in itself.‘Cognitive identity’ then means that when Intellect isthinking, it is thinking itself. Further, Plotinus believed thatAristotle, in book 12 of hisMetaphysics and in book 3 of hisDe Anima supported both the eternality of Intellect (inAristotle represented as the Unmoved Mover) and the idea thatcognitive identity characterized its operation.

Philosophically, Plotinus argued that postulating Forms without asuperordinate principle, the One, which is virtually what all theForms are, would leave the Forms in eternal disunity. If this werethe case, then there could be no necessary truth, for all necessarytruths, e.g., 3 + 5 = 8, express a virtual identity, as indicated hereby the ‘=’ sign. Consider the analogy ofthree-dimensionality and solidity. Why are these necessarilyconnected in a body such that there could not be a body that had onewithout the other? The answer is that body is virtuallythree-dimensionality and virtually solidity. Boththree-dimensionality and solidity express in different ways what abody is.

The role of Intellect is to account for the real distinctness of theplethora of Forms, virtually united in the One. Thus, in the abovemathematical example, the fact that numbers are virtually united doesnot gainsay the fact that each has an identity. The way that identityis maintained is by each and every Form being thought by an eternalIntellect. And in this thinking, Intellect ‘attains’ theOne in the only way it possibly can. It attains all that can bethought; hence, all that can be thought ‘about’ theOne.

Intellect is the principle of essence or whatness or intelligibilityas the One is the principle of being. Intellect is an eternalinstrument of the One’s causality (see V 4. 1, 1–4; VI 7. 42, 21–23).The dependence of anything ‘below’ Intellect is owing tothe One’s ultimate causality along with Intellect, which explains, viathe Forms, why that being is the kind of thing it is. Intellect needsthe One as cause of its being in order for Intellect to be aparadigmatic cause and the One needs Intellect in order for there tobe anything with an intelligible structure. Intellect could notsuffice as a first principle of all because the complexity of thinking(thinker and object of thought and multiplicity of objects of thought)requires as an explanation something that is absolutely simple. Inaddition, the One may even be said to need Intellect to produceIntellect. This is so because Plotinus distinguishes two logical‘phases’ of Intellect’s production from the One (see V1. 7). The first phase indicates the fundamental activity ofintellection or thinking; the second, the actualization of thinkingwhich constitutes the being of the Forms. This thinking is the wayIntellect ‘returns’ to the One.

The third fundamental principle is Soul. Soul isnot theprinciple of life, for the activity of Intellect is the highestactivity of life. Plotinus associates life with desire. But in thehighest life, the life of Intellect, where we find the highest form ofdesire, that desire is eternally satisfied by contemplation of the Onethrough the entire array of Forms that areinternal to it.Soul is the principle of desire for objects that areexternalto the agent of desire. Everything with a soul, from human beings tothe most insignificant plant, acts to satisfy desire. This desirerequires it to seek things that are external to it, such as food.Even a desire for sleep, for example, is a desire for a state otherthan the state which the living thing currently is in. Cognitivedesires, for example, the desire to know, are desires for that whichis currently not present to the agent. A desire to procreate is, asPlato pointed out, a desire for immortality. Soul explains, asunchangeable Intellect could not, the deficiency that is implicit inthe fact of desiring.

Soul is related to Intellect analogously to the way Intellect isrelated to the One. As the One is virtually what Intellect is, soIntellect is paradigmatically what Soul is. The activity ofIntellect, or its cognitive identity with all Forms, is the paradigmfor all embodied cognitive states of any soul as well as any of itsaffective states. In the first case, a mode of cognition, such asbelief, images Intellect’s eternal state by being arepresentational state. It represents the cognitive identity ofIntellect with Forms because the embodied believer is cognitivelyidentical with a concept which itself represents or images Forms. Inthe second case, an affective state such as feeling tired representsor images Intellect (in a derived way) owing to the cognitivecomponent of that state which consists in the recognition of its ownpresence. Here,x’s being-in-the-state is theintentional object ofx’s cognition. Where the affectivestate is that of a non-cognitive agent, the imitation is even moreremote, though present nevertheless. It is, says Plotinus, like thestate of being asleep in comparison with the state of being awake (seeIII 8. 4). In other words, it is a state that produces desire that isin potency a state that recognizes the presence of the desire, a statewhich represents the state of Intellect. In reply to the possibleobjection that a potency is not an image of actuality, Plotinus willwant to insist that potencies are functionally related to actualities,not the other way around, and that therefore the affective states ofnon-cognitive agents can only be understood as derived versions of theaffective and cognitive states of souls closer to the ideal of both,namely, the state of Intellect.

There is another way in which Soul is related to Intellect asIntellect is related to the One. Plotinus distinguishes betweensomething’s internal and external activity (see V 4. 2, 27–33). The(indescribable) internal activity of the One is its ownhyper-intellectual existence. Its external activity is justIntellect. Similarly, Intellect’s internal activity is itscontemplation of the Forms, and its external activity is found inevery possible representation of the activity of being eternallyidentical with all that is intelligible (i.e., the Forms). It is alsofound in the activity of soul, which as a principle of‘external’ desire images the paradigmatic desire ofIntellect. Anything that is understandable is an external activity ofIntellect; and any form of cognition of that is also an externalactivity of it. The internal activity of Soul includes the plethoraof psychical activities of all embodied living things. The externalactivity of Soul is nature, which is just the intelligible structureof all that is other than soul in the sensible world, including boththe bodies of things with soul and things without soul (see III 8. 2).The end of this process of diminishing activities is matter which isentirely bereft of form and so of intelligibility, but whose existenceis ultimately owing to the One, via the instrumentality of Intellectand Soul.

According to Plotinus, matter is to be identified with evil andprivation of all form or intelligibility (see II 4). Plotinus holdsthis in conscious opposition to Aristotle, who distinguished matterfrom privation (see II 4. 16, 3–8). Matter is what accounts for thediminished reality of the sensible world, for all natural things arecomposed of forms in matter. The fact that matter is in principledeprived of all intelligibility and is still ultimately dependent onthe One is an important clue as to how the causality of the latteroperates.

If matter or evil is ultimately caused by the One, then is not theOne, as the Good, the cause of evil? In one sense, the answer isdefinitely yes. As Plotinus reasons, if anything besides the One isgoing to exist, then there must be a conclusion of the process ofproduction from the One. The beginning of evil is the act ofseparation from the One by Intellect, an act which the One itselfultimately causes. The end of the process of production from the Onedefines a limit, like the end of a river going out from its sources.Beyond the limit is matter or evil.

We may still ask why the limitless is held to be evil. According toPlotinus, matter is the condition for the possibility of there beingimages of Forms in the sensible world. From this perspective, matteris identified with the receptacle or space in Plato’sTimaeusand the phenomenal properties in the receptacle prior to theimposition of order by the Demiurge. The very possibility of asensible world, which is impressively confirmed by the fact that thereis one, guarantees that the production from the One, which mustinclude all that is possible (else the One would be self-limiting),also include the sensible world (see I 8. 7). But the sensible worldconsists of images of the intelligible world and these images couldnot exist without matter.

Matter is only evil in other than a purely metaphysical sense when itbecomes an impediment to return to the One. It is evil whenconsidered as a goal or end that is a polar opposite to the Good. Todeny the necessity of evil is to deny the necessity of the Good (I 8.15). Matter is only evil for entities that can consider it as a goalof desire. These are, finally, only entities that can beself-conscious of their goals. Specifically, human beings, by optingfor attachments to the bodily, orient themselves in the direction ofevil. This is not because body itself is evil. The evil in bodies isthe element in them that is not dominated by form. One may bedesirous of that form, but in that case what one truly desires is thatform’s ultimate intelligible source in Intellect. More typically,attachment to the body represents a desire not for form but a corruptdesire for the non-intelligible or limitless.

3. Human Psychology and Ethics

The drama of human life is viewed by Plotinus against the axis ofGood and evil outlined above. The human person is essentially a soulemploying a body as an instrument of its temporary embodied life (seeI 1). Thus, Plotinus distinguishes between the person and thecomposite of soul and body. That person is identical with a cognitiveagent or subject of cognitive states (see I 1. 7). An embodied personis, therefore, a conflicted entity, capable both of thought and ofbeing the subject of the composite’s non-cognitive states, such asappetites and emotions.

This conflicted state or duality of personhood is explained by thenature of cognition, including rational desire. Rational agents arecapable of being in embodied states, including states of desire, andof being cognitively aware that they are in these states. So, aperson can be hungry or tired and be cognitively aware that he is inthis state, where cognitive awareness includes being able toconceptualize that state. But Plotinus holds that the state ofcognitive awareness more closely identifies the person than does thenon-cognitive state. He does so on the grounds that all embodied orenmattered intelligible reality is an image of its eternal paradigm inIntellect. In fact, the highest part of the person, one’s ownintellect, the faculty in virtue of which persons can engage innon-discursive thinking, is eternally ‘undescended’. Itis eternally doing what Intellect is doing. And the reason forholding this is, based on Plotinus’ interpretation of Plato’sRecollection Argument inPhaedo (72e-78b), that our ability toengage successfully in embodied cognition depends on our having accessto Forms. But the only access to Forms is eternal access by cognitiveidentification with them. Otherwise, we would have only images orrepresentations of the Forms. So, we must now be cognitivelyidentical with them if we are going also to use these Forms as a wayof classifying and judging things in the sensible world.

A person in a body can choose to take on the role of a non-cognitiveagent by acting solely on appetite or emotion. In doing so, thatperson manifests a corrupted desire, a desire for what is evil, thematerial aspect of the bodily. Alternatively, a person can distancehimself from these desires and identify himself with his rationalself. The very fact that this is possible supplies Plotinus withanother argument for the supersensible identity of the person.

Owing to the conflicted states of embodied persons, they are subjectto self-contempt and yet, paradoxically, ‘want to belong tothemselves’. Persons have contempt for themselves because onehas contempt for what is inferior to oneself. Insofar as personsdesire things other than what Intellect desires, they desire thingsthat are external to themselves. But the subject of such desires isinferior to what is desired, even if this be a state of fulfilleddesire. In other words, if someone wants to be in state B when he isin state A, he must regard being in state A as worse than being instate B. But all states of embodied desire are like this. Hence, theself-contempt.

Persons want to belong to themselves insofar as they identifythemselves as subjects of their idiosyncratic desires. They do thisbecause they have forgotten or are unaware of their true identity asdisembodied intellects. If persons recognize their true identity,they would not be oriented to the objects of their embodied desire butto the objects of intellect. They would be able to look upon thesubject of those embodied desires as alien to their true selves.

Plotinus views ethics according to the criterion of whatcontributes to our identification with our higher selves and whatcontributes to our separation from that identification. All virtuouspractices make a positive contribution to this goal. But virtues canbe graded according to how they do this (see I 2). The lowest form ofvirtues, what Plotinus, following Plato, calls ‘civic’ or‘popular’, are the practices that serve to control theappetites (see I 2. 2). By contrast, higher‘purificatory’ virtues are those that separate the personfrom the embodied human being (I 2. 3). One who practicespurificatory virtue is no longer subject to the incontinent desireswhose restraint constitutes mere civic or popular virtue. Such aperson achieves a kind of ‘likeness to God’ recommended byPlato atTheaetetus 176a-b. Both of these types of virtue areinferior to intellectual virtue which consists in the activity of thephilosopher (see I 2. 6). One who is purified in embodied practicescan turn unimpeded to one’s true self-identity as a thinker.

Plotinus, however, while acknowledging the necessity of virtuousliving for happiness, refuses to identify them. Like Aristotle,Plotinus maintains that a property of the happy life is itsself-sufficiency (see I.1.4–5). But Plotinus does not agree that alife focused on the practice of virtue is self-sufficient. EvenAristotle concedes that such a life is not self-sufficient in thesense that it is immune to misfortune. Plotinus, insisting that thebest life is one that is in fact blessed owing precisely to itsimmunity to misfortune, alters the meaning of‘self-sufficient’ in order to identify it with theinterior life of the excellent person. This interiority orself-sufficiency is the obverse of attachment to the objects ofembodied desires. Interiority is happiness because the longing forthe Good, for one who is ideally an intellect, is satisfied bycognitive identification with all that is intelligible. If this isnot unqualifiedly possible for the embodied human being, it does atleast seem possible that one should have a second order desire,deriving from this longing for the Good, that amounts to a profoundindifference to the satisfaction of first order desires.Understanding that the good for an intellect is contemplation of allthat the One is means that the will is oriented to one thing only,whatever transient desires may turn up.

4. Beauty

Plotinus’ chronologically first treatise, ‘On Beauty’ (I6), can be seen as parallel to his treatise on virtue (I 2). In it,he tries to fit the experience of beauty into the drama of ascent tothe first principle of all. In this respect, Plotinus’ aesthetics isinseparable from his metaphysics, psychology, and ethics.

As in the case of virtue, Plotinus recognizes a hierarchy of beauty.But what all types of beauty have in common is that they consist inform or images of the Forms eternally present in Intellect (I 6. 2).The lowest type of beauty is physical beauty where the splendor of theparadigm is of necessity most occluded. If the beauty of a body isinseparable from that body, then it is only a remote image of thenon-bodily Forms. Still, our ability to experience such beauty servesas another indication of our own intellects’ undescended character. Werespond to physical beauty because we dimly recognize its paradigm.To call this paradigm ‘the Form of Beauty’ would besomewhat misleading unless it were understood to include all the Formscognized by Intellect. Following Plato inSymposium, Plotinustraces a hierarchy of beautiful objects above the physical,culminating in the Forms themselves. And their source, the Good, isalso the source of their beauty (I 6. 7). The beauty of the Goodconsists in the virtual unity of all the Forms. As it is the ultimatecause of the complexity of intelligible reality, it is the cause ofthe delight we experience in form (see V 5. 12).

5. Principal Opponents

Plotinus regarded himself as a loyal Platonist, an accurate exegete ofthe Platonic revelation. By the middle of the 3rd century CE, thephilosophical world was populated with a diverse array ofanti-Platonists. In theEnneads, we find Plotinus engagedwith many of these opponents of Platonism. In his creative response tothese we find many of his original ideas.

Although Plotinus was glad to mine Aristotle’s works for distinctionsand arguments that he viewed as helpful for explicating the Platonicposition, there were a number of issues on which Plotinus thought thatAristotle was simply and importantly mistaken. Perhaps the major issueconcerned the nature of a first principle of all. Plotinus recognizedthat Aristotle agreed with Plato that (1) there must be a firstprinciple of all; (2) that it must be unique; and (3) that it must beabsolutely simple. But Aristotle erred in identifying that firstprinciple with the Unmoved Mover, fully actual self-reflexiveintellection. Plotinus did not disagree that there must be an eternalprinciple like the Unmoved Mover; this is what the hypostasisIntellect is. But he denied that the first principle of all could bean intellect or intellection of any sort, since intellection requiresa real distinction between the thinking and the object of thinking,even if that object is the thinker itself. A real distinction indicates some sort of complexity or compositeness in the thing (a real minor distinction) or among things (a real major distinction); by contrast, in a conceptual distinction, one thing is considered from different perspectives or aspects. In the absolutely simple first principle of all, there can be no distinct elements or parts at all. In fact, the firstprinciple of all, the Good or the One, must be beyond thinking if itis to be absolutely simple. The misguided consequence of holding thisview, according to Plotinus, is that Aristotle then misconceives beingsuch that he identifies it with substance or ousia. But for the firstprinciple of all actually to be such a principle, it must be unlimitedin the way that ousia is not. As a result, Aristotle makes manymistakes, especially in metaphysics or ontology.

The second group of major opponents of Platonism were the Stoics. TheEnneads are filled with anti-Stoic polemics. These polemicsfocus principally on Stoic materialism, which Plotinus finds to beincapable of articulating an ontology which includes everything in theuniverse. More important, Stoic materialism is unable to provideexplanatory adequacy even in the realm in which the Stoics felt mostconfident, namely, the physical universe. For example, the Stoics,owing to their materialism, could not explain consciousness orintentionality, neither of which are plausibly accounted for inmaterialistic terms. According to Plotinus, the Stoics were alsounable to give a justification for their ethical position – notin itself too far distant from Plato’s – since theirexhortations to the rational life could not coherently explain how onebody (the empirical self) was supposed to identify with another body(the ideal rational agent).

With regard to Plotinus’ contemporaries, he was sufficientlyexercised by the self-proclaimed Gnostics to write a separatetreatise, II 9, attacking their views. These Gnostics, mostly hereticChristians, whose voluminous and obscure writings, were only partiallyunearthed at Nag Hammadi in 1945 and translated in the last twodecades, were sufficiently close to Platonism, but, in Plotinus’view, so profoundly perverse in their interpretation of it, that theymerited special attention. The central mistake of Gnosticism,according to Plotinus, is in thinking that Soul is‘fallen’ and is the source of cosmic evil. As we haveseen, Plotinus, although he believes that matter is evil, vociferouslydenies that the physical world is evil. It is only the matter thatunderlies the images of the eternal world that is isolated from allintelligible reality. The Gnostics ignore the structure of Platonicmetaphysics and, as a result, wrongly despise this world. ForPlotinus, a hallmark of ignorance of metaphysics is arrogance, thearrogance of believing that the elite or chosen possess specialknowledge of the world and of human destiny. The idea of a secretelect, alone destined for salvation – which was what theGnostics declared themselves to be – was deeply at odds withPlotinus’ rational universalism.

6. Influence

Porphyry’s edition of Plotinus’Enneads preserved forposterity the works of the leading Platonic interpreter of antiquity.Through these works as well as through the writings of Porphyryhimself (234 – c. 305 C.E.) and Iamblichus (c. 245–325C.E.), Plotinus shaped the entire subsequent history of philosophy.Until well into the 19^th century, Platonism was in largepart understood, appropriated or rejected based on its Plotinianexpression and in adumbrations of this.

The theological traditions of Christianity, Islam, and Judaism all,in their formative periods, looked to ancient Greek philosophy for thelanguage and arguments with which to articulate their religiousvisions. For all of these, Platonism expressed the philosophy thatseemed closest to their own theologies. Plotinus was the principalsource for their understanding of Platonism.

Through the Latin translation of Plotinus by Marsilio Ficinopublished in 1492, Plotinus became available to the West. The firstEnglish translation, by Thomas Taylor, appeared in the late18^th century. Plotinus was, once again, recognized as themost authoritative interpreter of Platonism. In the writings of theItalian Renaissance philosophers, the 15^th and16^th century humanists John Colet, Erasmus of Rotterdam,and Thomas More, the 17^th century Cambridge Platonists, andGerman idealists, especially Hegel, Plotinus’ thought was the(sometimes unacknowledged) basis for opposition to the competing andincreasingly influential tradition of scientific philosophy. Thisinfluence continued in the 20^th century flowering ofChristian imaginative literature in England, including the works ofC.S. Lewis and Charles Williams.

Bibliography

A. Primary Literature

• Plotinus, 7 volumes, Greek text with English translation byA.H. Armstrong, Cambridge, MA: Loeb Classical Library, 1968–88.
• Plotinus. The Enneads, edited by Lloyd P. Gerson, andtranslated by George Boys-Stones, John M. Dillon, Lloyd P. Gerson,R.A. King, Andrew Smith and James Wilberding, Cambridge: CambridgeUniversity Press, 2018.
• Plotinus. The Enneads, translated by Stephen MacKenna,abridged and edited by John Dillon, London: Penguin Books, 1991.
• Neoplatonic Philosophy. Introductory Readings, translationsof portions of the works of Plotinus, Porphyry, Iamblichus, andProclus by John Dillon and Lloyd P. Gerson, Indianapolis: Hackett,2004.
• Plotin. Traites, 9 volumes, French translation withcommentaries by Luc Brisson and J.-F. Pradéau, et al., Paris:Flammarion, 2002–2010.

B. Secondary Literature

• Blumenthal, H.J., 1971,Plotinus’ Psychology, The Hague:Martinus Nijhoff.
• Bussanich, J., 1988,The One and its Relation to Intellect inPlotinus, Leiden: Brill.
• Caluori, D., 2015,Plotinus on the Soul, Cambridge:Cambridge University Press.
• Emilsson, E., 1988,Plotinus on Sense-Perception,Cambridge: Cambridge University Press.
• –––, 2007,Plotinus on Intellect, Oxford:Oxford University Press.
• –––, 2017,Plotinus, London:Routledge.
• Gerson, Lloyd P., 1994,Plotinus (Series: Arguments of thePhilosophers), London: Routledge.
• Gerson, Lloyd P. (ed.), 1996,The Cambridge Companion toPlotinus, Cambridge: Cambridge University Press.
• ––– (ed.), 2010,The Cambridge History ofPhilosophy in Late Antiquity, 2 vols., Cambridge: CambridgeUniversity Press.
• Gurtler, G.M., 1988,Plotinus: The Experience of Unity, NewYork: Peter Lang.
• Kalligas, P, 2014,The Enneads of Plotinus: A Commentary(Volume 1: Enneads I–III), Princeton: Princeton University Press.
• O’Brien, D., 1991,Plotinus on the Origin of Matter,Naples: Bibliopolis.
• O’Meara, Dominic, 1993,Plotinus: An Introduction to theEnneads, Oxford: Oxford University Press.
• Rappe, S., 2000,Reading Neoplatonism: Non-discursive Thinkingin the Texts of Plotinus, Proclus, and Damascius, Cambridge:Cambridge University Press.
• Remes, Pauliina, 2007,Plotinus on Self. The Philosophy of the‘We’, Cambridge: Cambridge University Press.
• Rist, J., 1967,Plotinus: The Road to Reality, Cambridge:Cambridge University Press.

C. Reference

• Dufour, Richard, 2002,Plotinus: A Bibliography1950–2000, Leiden: E.J. Brill. See in particular thereferences to the numerous commentaries on particular treatises in theEnneads, some of which are in English.

Academic Tools

	How to cite this entry.
	Preview the PDF version of this entry at theFriends of the SEP Society.
	Look up this entry topic at theInternet Philosophy Ontology Project (InPhO).
	Enhanced bibliography for this entryatPhilPapers, with links to its database.

Other Internet Resources

• The Life and Works of Plotinus, a short podcast by Peter Adamson introducing Plotinus (King’s College London and LMU Munich).
• The International Society for Neoplatonic Studies.
• Neoplatonism at Yahoo.
• International Plato Society.

Related Entries

Aristotelianism: in the Renaissance |beauty |Ficino, Marsilio |Neoplatonism |Plato:Timaeus |Platonism: in metaphysics |Porphyry |soul, ancient theories of