[In the following essay, Strange analyzes how, in Ennead 3.7, Plotinus attempts to overcome problems concerning eternity and time.]

Plotinus's treatise on eternity and time, Ennead 3.7 in Porphyry's edition of his master's works, has been among the most widely read of his treatises, not only due to its intrinsic philosophical interest and historical importance, but also because it is one of the most accessible and self-contained of Plotinus's writings. Unlike most of Plotinus's treatises, Ennead 3.7 does not at first seem to presuppose on the part of the reader either an extensive knowledge of the inner workings of Plotinus's metaphysical system or an intimate familiarity with specific issues of scholastic controversy in the first centuries a.d. It takes the form of a detailed philosophical commentary on the fundamental texts about eternity and time from the classical period of Greek philosophy. These are texts that even now retain their central interest for us: Plato's distinction between eternity and time in the Timaeus (37c-39a), Parmenides' argument for the timeless nature of being that lies behind Plato's distinction (B8.1-22), and Aristotle's account of the nature of time in the Physics (4.10-14). Nevertheless, despite its relative popularity, this treatise, like the rest of Plotinus's writings, presents great difficulties which still stand in the way of an adequate understanding of it. Commentators on the treatise tend to be content with repeating what they take to be Plotinus's doctrines about the nature of eternity and time, without any real attempt to come to terms with his arguments for them.¹ But properly understanding a philosopher does not consist merely in learning the catechism of his positions: a philosopher, especially a deep and difficult systematic thinker like Plotinus, cannot really be understood apart from his arguments, which allow us to see the philosophical reasons for holding the views that he does. It seems worthwhile, therefore, to try to trace the overall outlines of the argument of Ennead 3.7 in the hope of elucidating Plotinus's views about eternity and time.

I. ENNEAD 3.7 AND PLOTINUS'S PHILOSOPHICAL METHOD

It will be impossible fully to appreciate the arguments of Ennead 3.7 without first coming to understand Plotinus's conception of how one goes about arguing for a philosophical position. Indeed, I think that the failure to get clear about his methodology has contributed significantly to misunderstandings of Plotinus's work in general.² There is less excuse for this in the case of our treatise than there is with most of Plotinus's work, for it is here that Plotinus makes his most self-conscious remarks about what he takes to be proper philosophical method.

Plotinus takes the proper method of philosophy to be what I will call a dialectical method, in a sense that has become familiar from recent work on Aristotle's methodology. Indeed, it seems to me that Plotinus is quite self-conscious in adopting Aristotle's philosophical method, as he understands it, to his own practice. As is now widely recognized, Aristotle's method of investigating any subject is characteristically to survey first the views of “the many,” i.e., commonly accepted opinions, and those of “the wise,” i.e., the views of previous philosophers, on the subject; to compare and contrast these endoxa, the authoritative or reputable opinions, noting their agreements and disagreements with one another; and then to use these agreements and disagreements and his own dialectical ingenuity and techniques (discussed in the Topics) to develop the salient philosophical puzzles or aporiai that arise about the subject matter. The final stage of the inquiry is then to resolve these puzzles by drawing the requisite distinctions in order to show how the various authoritative views, or as many of them as possible, can be reconciled with one another, and their apparent difficulties and contradictions minimized.³ What is crucial is that this last stage is supposed to be sufficient: no further justification is taken to be required for the distinctions that one draws except that they are what is needed to resolve the conflicts among the authorities. Thus, in the Nicomachean Ethics, Aristotle is willing to say that if we manage to do this, “enough will have been shown” … NE 1145b6), and even that the resolution of the puzzles amounts to discovery (… NE 1146b7-8), presumably the discovery of the truth about the matter under investigation.

There is a well-known difficulty about how Aristotle's reliance on this dialectical method in his treatises is supposed to fit with his official view of theoretical understanding based on the explicitly nondialectical notion of demonstration of the Analytics. Presumably he thinks that if a dialectical investigation has been properly conducted, the distinctions that are indicated to resolve the salient puzzles will reflect or embody the proper principles of the subject matter in question.⁴ Plotinus, however, need not have been disturbed by this problem: he could just have followed the Academic tradition in assuming, probably correctly, that Aristotle in his treatises is merely employing the method of dialectical argumentation he had learned in Plato's Academy.⁵ This would be enough to persuade Plotinus, as a committed Platonist and defender of what he takes to be Plato's views, that the philosophical method practiced and encouraged by Aristotle was the correct one. In any case, the method that Plotinus adopts as his own is very close to that of Aristotle. As I will argue, this can clearly be seen both from Plotinus's methodological remarks in Ennead 3.7 and from his actual procedure in the treatise.

Plotinus begins the first chapter of Ennead 3.7 with some remarks on the great difficulty of the concepts of eternity and time. We—he seems to mean “we Platonists”—are always going around talking as if we understand what eternity and time are, as features, respectively, of the intelligible and sensible worlds (as Plato had argued in Timaeus 37c-38b).⁶ We speak as if we possessed a clear impression of what they are … (Ennead 3.7.1, 4-6). But in fact we do not, as becomes apparent as soon as we try to make our concepts of them explicit.⁷ Nevertheless, rather than investigating these concepts further in order to get clear about them, Plotinus says, we are generally satisfied just to parrot the relevant texts of those he calls “the ancients” … i.e., the philosophers of the classical period,⁸ even though we understand these texts in different and often contradictory ways (3.7.1, 7-13). Plotinus considers such an attitude to be quite unphilosophical; it is perhaps this sort of reproach he had in mind when he referred to his famous contemporary, the Platonist Longinus, as “a scholar, but certainly no philosopher” … Porphyry, Life of Plotinus 14.19-20). To be sure, Plotinus goes on to say that we should think that at least some of the ancient and blessed philosophers have discovered the truth about these matters⁹—I will have more to say about this claim shortly—but he declares that it is incumbent upon us to investigate which of them has done so, and how we ourselves can also reach a correct understanding of them. This means that we will have to work through their views in order to fully understand and evaluate them: as in Aristotle, this is the job of dialectic. We examine their views, however, not for their own sake but to gain an understanding of the subject for ourselves—Plotinus makes it clear later in the treatise that he has no interest in the history of philosophy … for its own sake (3.7.10, 9-11).

The opinions of the ancient philosophers seem to play the same sort of role for Plotinus as do the endoxa of the wise for Aristotle. What corresponds for Plotinus to the other source of Aristotelian endoxa, the opinions of the many? This becomes apparent from Plotinus's remarks at the beginning of his discussion of time in chapter seven of the treatise. He says there that if it had been the case that none of the ancient and blessed men had said anything about the subject of time, we would then be obliged to develop our own account of it, but that in doing so we would need to make sure that our opinion fit with … “the conception … we possess of it” (3.7.7, 14). This is a reference to the theory of “common conceptions” or “natural conceptions” … often conflated in post-Hellenistic usage with the “preconceptions” … of Epicurus), a theory which seems to have been originally formulated in Stoicism, but which by Imperial times had become common philosophical currency among the various schools.¹⁰ Common conceptions are beliefs that are shared by all (or nearly all) human beings about the contents of our concepts of things,¹¹ and the Stoics agreed with Aristotle (e.g., NE 1098b28-29) that such commonly held beliefs, while they could be confused, could not be completely false or off the mark, and hence that they can provide a reliable guide for inquiry.¹² Alexander of Aphrodisias (In Met. 9.19ff.) straightforwardly identifies natural conceptions with Aristotle's opinions of “the many”;¹³ Platonists tended to identify them with the objects of recollection (cf. Alcinous, Didaskalikos §4, 155.23-30 Hermann). Presumably the reason that they cannot be false is that, since they are shared by everyone, they must arise naturally in human beings, and Nature, as Peripatetics, Stoics, and Platonists could all agree, does nothing in vain.¹⁴ Plotinus would agree with this too, and he followed earlier Platonists in assimilating common conceptions to the inborn notions that are our confused earthly reminiscences of the Ideas.¹⁵

But while our common conceptions or shared ordinary notions can provide reliable guideposts for our inquiry, in that any statement that conflicts with them has no chance of being true, they are unclear and can as they stand provide no insight into the nature of things.¹⁶ We must therefore use philosophical analysis to help us understand things that we already have some awareness of, but are unable to define for ourselves adequately without reflection.¹⁷ Here Plotinus insists that we must respect the opinions of the ancients, that is, we must control our analysis by reference to the views of the wise. In the passage of Ennead 3.7.7 just cited he goes on to say that as it is, i.e., since the ancient philosophers have said something about the nature of time, we must not seek to develop our own account of it without first examining the previous views about it in order to see if our account will be in agreement with any one of them. … Presumably our account will have to be in agreement with at least one of them, since Plotinus has already indicated that he assumes that at least some of the ancient philosophers will have reached a correct understanding of the nature of time.

There are two ways in which Plotinus's dialectical method, while closely resembling it and surely based on it, differs from Aristotle's. The first is the pride of place that Plotinus is prepared to grant to the opinions of the ancient philosophers over those of the many¹⁸—hence what may be called Plotinus's scholasticism. Common conceptions play a role in Plotinus's method analogous to that of the views of the many in Aristotle.¹⁹ As we shall see, Plotinus employs common conceptions as a standard to which positions taken in the dialectic are required to conform. But unlike Aristotle, he does not dialectically investigate the content of common conceptions themselves, probably because, as natural conceptions and the objects of recollection, their truth is taken to be guaranteed. But the most striking difference from Aristotle is that Plotinus accords a preeminent status among previous philosophers to those he takes to have been genuinely wise. Aristotle notoriously shows no special reverence for any of his predecessors: he seems arrogant enough to think that he is capable of reaching a deeper level of understanding than any of them had. Plotinus on the other hand appears antecedently committed to the belief that Plato, above all other figures in the history of philosophy, has attained to a godlike degree of understanding. On such a view, our task is to try to understand Plato, not to transcend him.

Plotinus, then, is a committed Platonist, and presents himself as an exponent of Platonist philosophy.²⁰ How can this apparently antecedent commitment to Plato's doctrines be seen as anything other than dogmatic and undialectical? Certainly Plotinus never allows his dialectical inquiry to call into question the truth of Plato's views. He cites Plato's texts almost scripturally, the way that until recently some contemporary philosophers used to cite Marx or Wittgenstein.²¹ The problem for Plotinus is how to understand Plato's doctrines, which are ex hypothesi held to be true, for Plotinus concedes that Plato is sometimes unclear and even apparently self-contradictory (cf. 4.8.1, 27-28; 4.4.22, 11-12). But this is because he is trying to express the nature of intelligible reality, which Plotinus thinks is very difficult to grasp and still harder to explain clearly to others in words even if one does understand it.

I think that Plotinus's Platonism can be defended to some extent from a charge of unphilosophical dogmatism if we understand it to be a hypothesis that he adopts in order to escape from this impasse. The defense might go something like this. It is our task as philosophers to try as hard as we can to understand the hidden intelligible nature of reality. This is very difficult, especially for us in our present fallen condition. But Plato's doctrines, though obscure, seem to provide a reliable guide for our investigation: they are obviously deep, they have stood the test of time without being refuted, no other philosopher's opinions appear to be better. Therefore, we should assume that they are true: they express, however obscurely, a true understanding of the nature of things. Plotinus may be seen as assuming that Plato was a sophos, a wise man; he had achieved or at least come close to the understanding of the nature of the One or the Good that on Plotinus's reading he alludes to in the Republic and describes obscurely in the second part of the Parmenides. Therefore, since Plato possessed an adequate understanding of the truth, what he says about it must be true, however hard to interpret his statements may be.²²

Our task is to try to reach a similar understanding for ourselves. It would of course follow from the fact that we understand a true theory of some subject that we understand that subject. Plato, however, never gives us a developed theory or complete view of any subject, only hints of such a theory, which we must then try to fill in by the dialectical investigations of the views of other philosophers who may have had wise or helpful things to say about the subject, insofar as their statements can be brought into line with what Plato says about it. Doing this may even help us to better understand what Plato himself says. For we do not assume that we can tell at the outset what it is that Plato is saying: we begin by assuming that his doctrines are true, but not that we know what they mean.

For the question of the nature of eternity and time, these other philosophers are Parmenides and Aristotle, respectively, whom Plotinus clearly takes to be authorities on these matters, though not as reputable as Plato, nor to be preferred to him.²³ His investigation of the nature of eternity and time thus amounts to exegesis and commentary on Plato's words about eternity and time in the Timaeus, in light of a dialectical investigation of the theories of other philosophers that aims to see how far these can be brought into line with what Plato says in the Timaeus, an investigation controlled throughout by appeal to our shared conceptions.

II. THE NATURE OF ETERNITY

The fundamental presupposition of Plotinus's investigation of eternity as well as that of time is Plato's statement at Timaeus 37d that time is the moving image … of eternity. Plotinus takes this to imply that eternity and time, whatever they may turn out to be, will be analogues of one another, so that their defining and characterizing properties will stand in relations of analogical correspondence to each other.²⁴ Further, since Plotinus also assumes, following the Timaeus (30c-31b), that the sensible cosmos of becoming as a whole is an image of the intelligible world of being, the world of Ideas which he identifies with the ‘animal itself’ of the Timaeus,²⁵ it follows that eternity stands in a relation to intelligible being that is similar to the relation that time has to sensible becoming, so that, for example, Being can be understood to exist in some sense in eternity, as becoming exists in time.

I will not undertake to discuss in detail Plotinus's treatment of eternity. I want, rather, to bring out some features of his main lines of argument, especially as they pertain to his later discussion of time, and to try to clear up a few misunderstandings of them. Richard Sorabji²⁶ has recently argued, in my view correctly, that this treatise contains the first clear articulation of what was later to become the classical doctrine of eternity as an eternal ‘now,’ which appears in Boethius (Consolatio 5, prose 6) and through him influences the medievals.²⁷ Sorabji also argues that the classical doctrine has been thought to be incoherent for the wrong reasons (though he has his own doubts about its coherence). I agree with him that the charge of incoherence need not be taken to have been proved. I will indicate briefly why I think this is so in the course of my comments on Plotinus's arguments.

Plotinus considers the nature of eternity in chapters two through six of Ennead 3.7, before turning to the nature of time in chapters seven through thirteen. He takes up eternity first because Plato had declared that time is an image of eternity, and a good way to understand the features of an image is first to understand its original.²⁸ His goal is to determine precisely what the property or properties of intelligible Being are in virtue of which we say that it is eternal and that it exists in eternity. He sets out to investigate what eternity is according to those thinkers who declare it to be something different from time (3.7.1, 17-18), i.e., those who hold that it is something other than mere everlasting duration. These thinkers are Plato and Parmenides, with perhaps a bow to Aristotle's description of eternity in On the Heavens 1.9 (279a23-28; cf. Ennead 3.7.3, 19 and 3.7.4, 42-43). In fact, Plotinus's discussion of eternity is more a commentary on Parmenides than on Plato, though Plato himself is of course dependent on Parmenides B8 at Timaeus 37e.²⁹

Plotinus finds himself at a loss for suitable candidate definitions of eternity to examine via his dialectical method, for eternity is not an object of everyday experience and hence not an ordinary notion about which there could be suitably authoritative common beliefs, and nothing that could count as a definition of eternity had been offered by the ancients. Indeed Plato, at Timaeus 37d, seems to have been the first to use the term αίwν in a way that does not denote any stretch of time. Plato however says very little about eternity and does not offer a definition of it. What he does say about eternity in the Timaeus can be summarized in the following three points, each of which Plotinus takes as fundamental for his discussion of the nature of eternity: (1) Eternity is a feature of the intelligible world, conceived as the paradigmatic animal itself. From Tim. 38c1-2 it appears that Plato is using the word αίwν not in a technical philosophical sense, but in its ordinary meaning in the Greek of his day, to refer to the lifespan of the animal.³⁰ (2) Eternity “remains in unity” … while time exhibits a regular motion, “proceeding according to number” … as its image (Tim. 37d6). (3) Eternity admits of no description involving tenses other than the present (Tim. 38ab). This last derives from Parmenides' argument for the timeless nature of Being, which both Plato and Plotinus identify with their intelligible world of Ideas. So even though Parmenides does not mention eternity by name, Plotinus quite naturally takes him to be talking about it.

With no actually proposed definitions of eternity to consider, Plotinus instead begins his discussion in Ennead 3.7.2 by raising puzzles about two possible candidate definitions of it that he apparently invents himself.³¹ These are suggested by the assumption that time is the image of eternity, Plato's condition (2), with its implication that eternity should therefore stand in a relation to the intelligible cosmos that is analogous to the relation of time to the sensible cosmos, itself an image of the intelligible animal itself. Possible definitions of time therefore ought to be analogous to possible definitions of eternity. Following this principle, Plotinus uses the proposed definitions of time he will consider later, which he takes from Aristotle's Physics 4.10, to generate possible definitions of eternity. Thus, eternity might be taken to be identical with intelligible substance itself, i.e., the whole of intelligible reality, as time was thought by some to be identical with the heavenly sphere (Physics 218b1), since each contains all the items belonging to their respective realms. Alternatively, eternity might be identified with intelligible rest or stability—… the Idea of rest (Ennead 3.7.2, 36)—as time was identified by some early thinkers with motion (Physics 218b10-11).

Neither of these proposed characterizations of eternity should be immediately ruled out as implausible. Plotinus himself wants to insist that intelligible entities must have their existence in some sense in eternity, just as all sensible things exist in time. The latter he takes to be part of the common conception of time, and the former is assumed to follow from it together with the principle that time is the image of eternity. But eternity cannot just be taken to be the whole of which the Ideas are parts, as physical things are parts of the body of the universe. Rather, eternity must be grounded in a property that applies to the Ideas in some other way, for intelligible substance as a whole and each of its parts, i.e., each of the Ideas, must be eternal in precisely the same sense (3.7.2, 10-15 and 17-19). This would not be the case if eternity was merely intelligible substance itself, for then the other Ideas could only be eternal by participation in it, and thus only derivatively.³² The second candidate definition, that eternity is just the stability or fixity of the Ideas, seems close to what is probably Plato's actual line of thought in the Timaeus passage where he stresses the contrast between the unchanging nature of the Ideas and the constant flux of sensible becoming.³³ Plotinus, however, refuses to accept such an interpretation of the Timaeus: he rightly insists that there must be something more to the eternity of the Ideas than their mere stability if eternity is going to be something different from time (cf. 3.7.2, 32-33), for rest or changelessness just as much as motion will be measured by time.

How does Plotinus think he can distinguish the eternal mode of being of the Ideas from that of merely temporally unchanging essences? We should be clear about what is at stake here. The Ideas, for Plotinus, as for the Plato of the Sophist and the Statesman, seem intended to ground not only the truth but also the necessity of universal judgments about the natures of things. That is, if “S is P” is such a judgment, then it is supposed to be necessarily true because S and P correspond to Ideas that stand in what the Sophist calls a relation of “communion” … with one another (Soph. 257a; cf. 250e) that is not a merely external relation and that cannot be otherwise than it is. The reason it cannot be otherwise is that Ideas are the sort of things that do not admit change. But why do they not admit change? Why is it impossible for their natures to be otherwise than they are? This seems a legitimate question, but if Ideas are merely stipulated as what is unchanging (as for instance at Tim. 27d), there can be no non-trivial answer to it, and in particular no answer that connects this feature of the Ideas with their nature as the objects of understanding and the causes of phenomena. All that can be said is that this is just how Ideas are. Perhaps Plato himself was content with this,³⁴ but it seems preferable to be able to give a principled reply to the question, and this is what Plotinus's theory of eternity, as we shall see, allows him to do.

With this in mind, let us turn to Plotinus's positive account of eternity in chapters three through six of our treatise. Here Plotinus attempts to derive the defining characteristics of eternity as the proper mode of being of intelligible reality by reflecting upon a number of considerations: (a) the conditions on eternity he finds in Plato's Timaeus; (b) Parmenides' arguments in B8 for the timeless nature of Being; (c) his own account of the fundamental logical structure of the intelligible world, based on … Plato's Sophist; (d) conditions drawn from the dialectical investigations of the two candidate definitions of eternity in chapter two; and finally (e) further considerations, adumbrated in chapter four, concerning the relative perfection or completeness of the intelligible world vis-à-vis the sensible, namely, that the intelligible world, as what is Being in the full or perfect sense, must be a perfect whole, and thus in complete possession of all of its parts (which are not parts of extension or duration, but rather consist in the multiplicity of the Ideas themselves).³⁵ The details of his arguments are somewhat obscure.³⁶ The characteristics of eternity that he ends up with are the following (cf. especially 3.7.3, 36-38; 3.7.5, 25-28).

Eternity is:

1. A sort of life …—for Plotinus, this means a kind of conscious or intentional activity

2. An activity that is essential to the intelligible realm …

3. Present all together (… 3.7.3, 37) as a complete whole³⁷

4. Not deficient in any respect, i.e., possessing perfect being 3.7.3, 37, and 3.7.4 passim)

5. Without any sort of extension (… 3.7.3, 37; cf. 3.7.3, 15)³⁸

6. Not admitting past or future—which follows from (3) and (4)

7. Infinite (… 3.7.5, 36)

… They are not logically independent of one another; in particular, (7) is supposed (cf. 3.7.5, 25-28) to be a consequence of (3)-(6). Hence, not all of (1)-(7) can belong to the definition of eternity. Plotinus connects (5) with Plato's description of eternity as “remaining in unity.”

The intelligible world is essentially alive for Plotinus because it is an infinite active intellect or divine mind … whose acts of thought are identical with the Ideas, and since it is a pure act, they are in turn the same as it, on the Aristotelian principle that actual intellect is the same as its objects. Given this conception of the nature of the intelligible, it is not unreasonable for Plotinus to take its proper mode of being to be a kind of life, which he identifies with the genus motion … of Plato's Sophist. (That this is to be identified with the life of the intelligible world Plotinus takes to be the indicated by Sophist 248e6-249a2.) … The crucial feature of this life that distinguishes it as eternal rather than merely changeless is that it is wholly present to itself, and is therefore without any sort of duration or extension.³⁹ What this means is that there are in no sense distinct moments, phases, or parts of this life (cf. 3.7.3, 19-20). If there were, it would not all be present at once: some of it would be in one part of itself and some in another, and hence its being at any point of itself would be imperfect, lacking some “part” of itself. This would imply a need to move toward perfection, and thus change and time (3.7.4, 15-28). All of it is simultaneously present, so to speak, at the unique single moment of eternity.⁴⁰

This is notoriously an extremely difficult concept to grasp. It has often been claimed to be incoherent. It is said, for instance, that it is impossible to conceive of any sort of life, even a timelessly eternal one, apart from duration⁴¹ or change.⁴² Plotinus would reply that this does not follow for the life of … intellect, which is a pure activity. … He thinks that such an activity, since it already contains within itself its goal … can be instantaneous and need not therefore in and of itself be in time.⁴³ He seems to be right at least in that nothing in Aristotle's conception of activity requires that activities involve duration. At Ennead 6.1.16, 16ff. he gives as an example the case of an instantaneous act of seeing (an Aristotelian example, cf. Met. 1048b23 and NE 1174a14-15), and in Ennead 1.5 he argues that the happiness of pure contemplation, as an activity, cannot increase over time, because, not being essentially something extended, it is not the sort of thing that can be measured by time—in fact, it is the same as eternal life (1.5.7, 26-30).

One might also be disturbed by Plotinus's repeated use of temporal language in describing eternity. He is quite prepared to speak of eternity as existing “now” (vũv; cf. Parmenides B8.5), and he quotes with approval Aristotle's folk-etymological derivation of … “eternity”, from … “always existing” (Ennead 3.7.4, 42; cf. Aristotle, On the Heavens 279a27; and Porphyry Sententiae §44, 58, 7-9 Lamberz). But “now” and “always,” it will be claimed, contain an implicit reference to other times beside the present: “now” indicates the present in contrast with other times, and “always” means “at all times, not only now.” Plotinus's reply is that he is using these terms here in extended senses—extended by analogy—and that hence they should not be understood as carrying with them their normal logical baggage. “Now,” for example, is being used in a way that explicitly contrasts with its ordinary use to indicate the present that joins the past to the future. Plotinus's notion of the eternal now has been carefully stripped of its association with past and future times, and is merely used to signify that the whole of an eternal being's life is present to it at once, analogously to the way that a bit of one's life is present to one in the temporally present moment. (Plotinus clearly believes that Parmenides B8.5 refers to an eternal, not a temporal now.⁴⁴) At Ennead 3.7.6, 21-36), Plotinus himself makes the point that “always” is used of eternity in an extended sense. …⁴⁵ This use can be misleading, he says, if it is not understood to mean, not that what is eternal goes on existing, but that it cannot not exist. Certainly he could have wished that Plato had been more cautious in the way he had used αεί of his eternal Ideas at Timaeus 38a3 without any sign of qualification.

If there is no duration or distinction within the life of eternity, then it is not logically possible for an eternal entity to undergo change or be otherwise than it is (cf. 3.7.5, 1-12). That would require another moment of its existence besides the present one in which it could be otherwise, and there are no such moments available. His conception of eternity thus gives Plotinus a clear way of explicating the difficult notion of the necessary being of the Ideas, without merely stipulating that they be unchanging essences. This view of eternal life is certainly paradoxical, but it has not been shown that it is incoherent or untenable. Plotinus's theory of eternity is an excellent and on its own terms largely successful example of his approach to the deeper metaphysical problems of Platonism.

III. THE DIALECTICAL INVESTIGATION OF TIME

Plotinus begins his dialectical investigation of time (3.7.7, 17 ff.) with a division of previous accounts of it into those that had treated it as a kind of motion or change … ; those that had taken it to be a subject of motion, i.e., the heavenly sphere; and those that had defined it as something that belongs to motion, i.e., a property or attribute of motion. This is an attempt to rationalize Aristotle's discussion of previous accounts of time at Physics 4.10.218a30-b20. According to this scheme, all previous accounts of time were agreed that it was somehow connected with motion—that is, physical motion, change in bodies⁴⁶—and such universal agreement ought on Plotinus's methodological principles to reflect a fact about the nature of time. Indeed, he remarks that our conception of time reveals it to be something that, like motion, is never the same and always in flux (3.7.7, 20-22). He follows Aristotle (Physics 4.10.218a30-b20) in rejecting that time could itself be any sort of physical motion or a subject of motion. Two of the arguments he gives for this are apparently original. The first is that time cannot itself be a motion because it is that in which motion occurs,⁴⁷ and must therefore be different from motion. That a container is distinct from what it contains is treated by Plotinus as a common conception, and indeed it appears as an assumption in the second, dialectical part of Plato's Parmenides (138b2-3). A later passage of our treatise shows that Plotinus takes the other premise of this argument, that all physical motion is in time, to be a part of our common conception of time (3.7.8, 45-47; cf. 3.7.10, 6).⁴⁸ The second argument is that motion can stop or cease but time cannot (3.7.8, 6-8). Presumably this also involves a reference to common conceptions or intuitions about time.

Since time can be neither motion nor what is in motion, we are left with the remaining accounts which treat it as something belonging to physical motion. Plotinus considers in detail the Stoic and Peripatetic versions, which further agree in defining time in terms of the quantitative aspect of physical motion. (He dismisses the Epicurean definition of time as the … “accompaniment” of motion at 3.7.10, 1-8 as being obviously inconsistent with our conception of time as the container of motion.) The Stoics had defined time as the extension … of motion, or of the motion of the universe. This means time is the proper extension of motion, itself thought of as a particular kind of continuous quantity, i.e., as just so much motion (cf. … 3.7.8, 37). Here the Stoics may have been following the lead of Speusippus, who had defined time as the quantity that is proper to motion … Plutarch Platonic Questions 1007 B [= Speusippus, fr. 53 Lang]). Plotinus's refutation of the Stoic definition takes the form of a trilemma. If they mean to identify time with the motion itself, considered as an extended quantity, this collapses back into the view just refuted, that time is a motion. If they mean that time is an extension that inheres in motion, the way magnitude inheres in physical body, then their definition will be inconsistent with our conception of time as that in which motion occurs: time on this view would be in the motion rather than the other way round. Only if they mean that time is a sort of extension that lies outside the motion and contains it, in the way that spatial extension contains bodies, will this fit the conception of time. But if so, they have not yet made clear the nature of this sort of extension.

If the view that time is the extension of motion means anything other than that it is the extended motion itself under some description, it is difficult to distinguish it from the Peripatetic conception of time as the measure or number of motion derived from Aristotle's Physics. Plotinus's elaborate discussion of this conception in chapter nine of the treatise amounts to a dialectical criticism of Aristotle's discussion of time in Physics 4.11-14. It is clear, however, that Plotinus is working here with material and arguments drawn from the previous Peripatetic commentary tradition of the Physics. This can be seen by comparing his discussion with the relevant passages of Simplicius's Physics commentary. As we will see, Plotinus is aware of the views of Alexander of Aphrodisias, and this suggests he may have been using here Alexander's lost commentary on the Physics, which is probably Simplicius's main or only source for the pre-Alexandrian tradition as well.⁴⁹

Rather than examining Plotinus's arguments against the Peripatetic conception one by one, it will be convenient instead to consider how he responds to the most obvious difficulties with Aristotle's account of time. These difficulties were clearly seen by the earlier Peripatetic commentators and will have been known to Plotinus through Alexander's commentary or other sources.

Aristotle defines time as the number (or measure⁵⁰) of motion according to the successive order or ‘before and after’ that it contains (Physics 219b1-2). We perceive this before and after through our awareness of a succession of moments or ‘nows’ in the course of the motion. Time is supposed to be somehow the measure of the motion thought of as an extended quantity bounded by the first and last of these nows, as the underlying subject of the motion takes time in getting from one to the other. Aristotle seems aware that this definition is obscure, and in attempting to clarify it in Physics 4.11-14, he gets himself into a number of well-known difficulties from which it is unclear how he is to be extricated. The four most important difficulties were noted by the Peripatetic commentators before Plotinus:

1. What motions or type of motion is it of which time is supposed to be the measure? This puzzle was raised already by Aristotle's pupil Eudemus (Simplicius, In Phys. 717.6-14). If Aristotle intends time to be the measure of motion in general, then this will include not only regular or uniform … motion⁵¹ but irregular and disorderly motion as well. But by definition irregular motion presents no repeatable units by which it can be measured (cf. Ennead 3.7.9, 5-6), hence it can only be measured by comparing it with simultaneous regular motion. Time in the strict sense will therefore be the measure of regular motion, since the measure of this sort of motion will be what measures the other sort of motion as well. Regular motions can however be faster or slower than one another, and hence will involve different measures of time. Which of these measures will be time in the primary or strict sense, according to the Aristotelian definition? Here the commentators are obviously thinking of the different temporal measures provided by the cycles of the various heavenly bodies, the day, month, year, and so forth, the different “measures of time” of Timaeus 39c-d. Aristotle could answer that it does not matter which of these one picks as the basic unit of measurement for time: since they stand to one another in fixed and definite ratios, any of them could in principle serve as the fundamental unit. Alexander quite plausibly held, however, that the primary unit of measure of time was given by the heavenly motion with the shortest natural unit, i.e., the swiftest motion. He was therefore led to identify time with sidereal time, the number of the motion of the outer sphere of the fixed stars.⁵² Plotinus remarks that this seems the best solution to the problem (3.7.9, 32-35).⁵³

2. What sort of number of measure is it that Aristotle has in mind as constituting time? In Physics 4.11-12, Aristotle says repeatedly that it is the number that is counted or measured, and not that which we use to count (Physics 219b5-9, 220b8-9). This distinction is taken by the commentators to be the same as the distinction between arithmetical or “monadic” number, composed of abstract units (Met. 1083b17; cf. Plato Philebus 56d-e) and concrete number, i.e., a number of objects of a given type, in this case units of motion or of time.⁵⁴ Aristotle illustrates this distinction in Physics 4.14 with the example of the numbers seven and ten as opposed to seven or ten dogs or horses (223b4-6, 224b12-15). The problem with Aristotle's claim here is that if time is the concrete or numbered number of motion, there will then necessarily be a different time (since there is a different number) for each distinct motion, even those which occur simultaneously. For Aristotle is committed to the view that different motions are really distinct from each other just in virtue of having distinct goals. … It appears that Alexander's predecessor Aspasius even wanted to change the text at Physics 219b6-7 in order to make Aristotle say there that time is numbering or abstract number, not numbered number (cf. Simplicius, In Phys. 714, 31-715, 13), and Alexander seems to have followed him in this.⁵⁵ As we shall see, Plotinus exploits this difficulty for his own purposes.

3. It is hard to see how Aristotle can explain how one and the same time can be simultaneously present everywhere (cf. Physics 219b10, 220b5-6), which Plotinus takes to be part of the common conception of time, unless he is willing to make time numbering number.⁵⁶ Aristotle seeks to account for this by arguing for the sameness of simultaneous nows at Physics 4.14.223b1-12, and returns to the issue in an appendix to this chapter at 224a2-17. What he seems to want to say there is that simultaneous motions share the same time because they share the same now (219b10-12)—not however numerically the same now, since on his official account particular nows have to be localized to particular motions, but the same now in being or in species.⁵⁷ This does not seem to suffice for what he wants, since the common conception is that the present time is numerically the same everywhere (as Aristotle appears to concede at 220b5-6), and time is on his definition a concrete number of nows. Hence he is forced to say that different simultaneous motions share the same now in the same way that seven horses and seven dogs share the same number, but this is to make time abstract or numbering number (cf. 220b8-9), and he thus contradicts his earlier insistence that time is a concrete number of nows.⁵⁸ This provides the motive for Aspasius's “emendation” at 219b6-7.

4. What is the nature of the relation between time and the soul that perceives it? Alexander held that all the above difficulties could be resolved if we understand the time that is marked off by nows to be numbering number, as suggested by Physics 220b8-9 (cf. Simplicius, In Phys. 729, 9-12), and consequently followed Aspasius's alteration of the text of 219b6-7. In accordance with his view of abstraction,⁵⁹ Alexander held that time in this sense, as abstract or numbering number, exists in thought, i.e., in the soul that perceives time, while the before and after in motion, which is what time numbers or measures, exists outside the soul in the movement of the heavenly sphere. Thought measures time by marking off the periods of the regularly repeating motion of this sphere, e.g., by successive sunrises or sunsets. This line of interpretation is clearly tailored to fit what is notoriously the most difficult and recalcitrant passage in Aristotle's discussion of time, namely Physics 4.14.223a21-29, which makes the claim that time cannot exist without soul to number it.⁶⁰ Plotinus has what seems the obvious objection to this: if time is the measure of the ordered succession in physical motion and this exists outside the soul, why does soul actually have to measure it before time can exist? That, Plotinus says, is like claiming that a physical magnitude cannot be the size it is unless someone happens to measure it (Ennead 3.7.9, 68-75 and 80-82). Plotinus suggests that this objection will stand regardless of whether time is taken to be numbering number or numbered number, and hence presents it as a dialectical counter against Aspasius's proposal that time is to be identified with numbering number. Even if Alexander can meet this objection, Plotinus thinks he has still established dialectically that time must be something ideal or in the soul, since the only remaining way to save Aristotle's theory involves conceding that time depends upon soul for its existence. Alexander's view takes care of the problem about the unity of a simultaneous time by defining simultaneous times as those that are perceived to co-occur: their nows are one and the same in the soul of the perceiver. On Alexander's interpretation, then, time becomes something ideal because it is a matter of the perception of the before and after in physical motion.⁶¹ In one passage Aristotle himself seems to concede that time is ideal in an even stronger sense. He notes that we do not need to perceive any physical motion at all in order to be aware of the passage of time: all that is required is that we be aware of a movement in our thought (219a4-8). Hence the existence of time need not be dependent on the existence of physical motion at all.

It is clear that Plotinus is aware of all these difficulties with Aristotle's account, and he uses them to raise puzzles of his own. However, his interest is not so much in refuting the theory as in understanding where and how it fails, so that he can improve upon it and avoid its pitfalls. He had already raised the difficulty about how to account for simultaneous motions in his discussion of the Stoic view of time (3.7.8, 29-30). In examining the Peripatetic view he contents himself with the remark that if time is something existing in motion, it will not be everywhere, but only in the motion it is in (3.7.9, 46-48; cf. our discussion of difficulty [2] above). He focusses instead on the related problem of whether time is numbered number or numbering number. He agrees with Alexander and Aspasius that it must be taken to be numbering number, but thinks that this too leads to problems. For one thing, he claims, we need to specify how this number measures motion (3.7.9, 45-46). If the Peripatetics claim that this takes place in virtue of the soul using it to measure motion, Plotinus will agree, but will protest that this does nothing to help define time (3.7.9, 83-84). For why should the definition of time include any reference to physical motion at all if there is psychic motion going on in the soul?⁶² We have seen that Aristotle sometimes seems to concede that there can be time without physical motion. Moreover, numbering number does not itself exhibit any temporal order, so where does the temporality of the order of time come from? Why should it be thought that the fact that it is number that is used to measure motion by itself gives rise to time (3.7.9, 12-17 and 53-55)? Here Plotinus sets a dilemma. Either the order of succession that is contained in motion must already be a temporal order before it is measured or counted, and Aristotle's definition of time turns out to be circular (cf. 3.7.9, 57-62), or the fact that number numbering motion is time is due to its being soul that does the measuring. But how can this be, Plotinus asks, unless soul is somehow the cause of time (3.7.9, 79-80)?⁶³

Plotinus's dialectical investigation has now cleared the way for his own full-blown idealist theory of the nature of time. All earlier physicalist views of the nature of time have now been refuted, along with physicalist interpretations of Aristotle's theory of time; as we will see, Plotinus thinks that the purified version of Aristotle's theory that his arguments leave standing is compatible with the truth about the nature of time.⁶⁴ He thinks his arguments have freed time from any essential links to the material world, while leaving it firmly attached to the soul; they have even suggested that the soul must be considered the cause of time. It remains for him to sketch in the remaining chapters of the treatise (3.7.11-13) an account of how soul generates time, and to show how this account accords both with common conceptions and with Plato's texts.

IV. THE POSITIVE ACCOUNT OF TIME

Plotinus's account of how the soul generates time is presented in Ennead 3.7.11. It is first introduced in the form of a rather odd and halfhearted myth, almost a parody of Platonic myths. The mythical trappings are apparently supposed to indicate that the account is not to be taken literally, for it is presented as an account of how soul first brought time into being, yet Plotinus certainly does not think that time ever literally had a beginning. What Plotinus is trying to express in this passage is rather the causal relation he sees as holding between the soul and time, the fact that soul generates time, and his saying that the soul existed “before” time is a clear if metaphorical way of putting the point that the soul, as the cause of the being of time, is ontologically prior to it.

According to Plotinus's myth, in the beginning time did not exist, except as an Idea in the intelligible world.⁶⁵ But there also existed in the intelligible world what Plotinus calls an “officious nature” (… 3.7.11, 15)⁶⁶ which wanted to be able to rule itself. This power set itself in motion;⁶⁷ time came into being along with its motion, and so “we” made time (3.7.11, 14-18). In the suceeding lines, Plotinus immediately goes on to provide an interpretation of his own myth. The soul in the intelligible world contains “a certain unquiet power” (… 3.7.11, 21), because of which it seeks to create something on its own, something more than what it possesses “already” in virtue of being a member of the intelligible world. This “unquiet power” of the soul is apparently its faculty of … desire, as comparison with Ennead 4.7.13 (beginning) and 4.3.7.1-8 seems to indicate (cf. also Ennead 6.8.2, 30-33), and the association of the “fall” of the soul from the intelligible realm with its desire to rule itself recalls the account of the fall of the soul in Ennead 5.1.1, 1-22.⁶⁸ However, it is impossible that the soul can really come to possess anything of its own outside the intelligible world since that world already contains the totality of being. Hence to satisfy its desire, the soul is forced to make for itself a world of appearance of its own, in the only way it can, in the image of the world it already knows, the world of Ideas. The world it makes for itself is the sensible world. Now, according to Plotinus, the essential feature of the soul that serves to distinguish it from intellect or νοûs is that whereas intellect is able to think many, indeed all, of its thoughts at once, soul must think discursively, one thought at a time (cf. 5.1.7, 42-43; 5.3.17, 23-24). Hence the fallen soul, which has separated itself from [nous], cannot think the entirety of true being all at once (cf. 3.7.11, 20-23, interpreting Timaeus 37d3-4), but must think of it part by part, and must think images of being, not being itself. Hence the soul's conscious activity is not all at once as is that of νοûs, but is extended and successive (cf. 3.7.11, 35-43): it is rather what Plotinus calls “discursion”. …⁶⁹ Therefore the stages of the soul's life are constantly different and successive, as one of its thoughts leads to another, and this defines and generates temporal succession as a construction out of the process of discursive mental activity. Moreover, the inner conscious activity of the soul is also what generates the physical universe itself: this is why the universe and all its motions occur in succession and within time (3.7.11, 27-36; cf. 3.7.12, 24-25).⁷⁰ Time is therefore constituted by the life of the soul (a non-physical sort of motion), which is itself an image of the eternal life of intellect: the analogical correspondence of their features is argued in detail in 3.7.11, 45-62. Time can thus be defined as “the life … of the soul in progressive movement from one stage of life … to another” (3.7.11, 43-45). On this view the dated linear succession of events derives from the psychological succession of thoughts: the ‘now’ of time is the present moment of consciousness.

Plotinus says that “we” made time (3.11.18): presumably “we” are here identified, as is common in the Enneads, with the individual rational soul. This seems inconsistent with the doctrine of Ennead 4.4.15-17, according to which it is the World Soul, not our souls, which generates time.⁷¹ But the closing passage of our treatise (3.7.13, 66-69) makes clear what Plotinus has in mind here: he is speaking of the hypostasis Soul as the generator of time.⁷² “We” can be identified with the hypostasis Soul in virtue of Plotinus's doctrine of “the unity of soul,” namely, that all individual souls, while remaining distinct from one another, are yet somehow also numerically one (cf. Ennead 4.9).⁷³ At Ennead 3.7.13, 66-69, this doctrine is appealed to in order to account for the common conception that the same time is simultaneously present everywhere. The view of Ennead 3.7.11-13 may indeed mark a development in Plotinus's views on the origin of time from those presented in Ennead 4.4, but since the World Soul and our souls are not here distinguished, it is still possible that the activity of the World Soul is to be given a preeminent role in the account of time, since it is still the soul that is responsible for the celestial revolutions that define time.⁷⁴

Plotinus attempts to confirm his claim that the soul is responsible for the being of time in chapter twelve (3.7.12, 4-25) by means of a thought experiment. Time, Plotinus argues, cannot be conceived to exist without the soul, as Aristotle indeed seems to concede, but the soul can be conceived to exist without time if it withdraws completely from its activity of discursive thought and returns to the unextended life of intellect. Since the ceasing of soul's discursive activity would abolish time, it must be this that generates time (3.7.12, 15-22). Now Alexander had claimed that Aristotle's view that time cannot exist without soul's activity was consistent with his own view that time is the number of the motion of the outermost heavenly sphere, since the soul of this sphere is the cause of its motion, which is in turn the cause of all other physical motion. Eliminating soul would therefore eliminate all motion as well (Simplicius In Phys. 759.18ff.; Alexander, On Time §16). Plotinus refutes this with the claim that we can imagine the rotation of the heavens could stop without the inner activity of the soul stopping: in that case soul would measure the state of rest of the universe just as it had formerly measured its motion, i.e., by using time (3.7.12, 17-19). Time would therefore, pace Alexander, still exist.⁷⁵

Plotinus claims that the main point on which the Peripatetic theory of the nature of time had gone astray was in taking time to be essentially a measuring concept. He thinks that time is not a measure, but is a quantity that only comes to be measured accidentally, by comparison with regular or uniform physical motion. Remarkably, he wishes to believe that this is what Aristotle had actually meant to say, and that he had come to be misunderstood because of his obscurity and the fact that he was writing for students who had heard his lectures (3.7.13, 9-18). Plotinus's point is that the process of thinking and its associated subjective time is a continuous uniform process, not naturally articulated into units by which it could be measured (cf. 3.7.12, 1-4). Indeed, it is a familiar fact of experience that we often cannot tell just subjectively how long something takes, without, e.g., looking at a clock. The purpose of the regular heavenly motions, as Plato had said in the Timaeus (47a) is to reveal the existence of time to our senses, but time is something imperceptible in itself (3.7.12, 25-33). Rather, the soul's activity measures itself by picking a simple unit of regularly repeated motion, e.g., the sweep of a watch's second hand or the movement of the stars, to use as a standard of comparison. Plotinus thus manages to sidestep the problems about time measurement that beset other idealistic theories of time, such as Locke's and Berkeley's, which attempt to hold onto Aristotle's notion of time as essentially a measuring concept.⁷⁶

Plotinus can claim to have argued for his theory of time in the proper dialectical manner, by showing that it provides a more adequate account of the phenomena of time than any other that had been proposed. He is able to account for the common conception that the same time is simultaneously everywhere by pointing to the soul and its life, which is time, as simultaneously present everywhere. Simultaneous times are also the same in the souls of all perceivers, since all souls, as Plotinus claims, are in a sense one and the same soul (3.7.13, 66-69). Time is connected with motion because it is the motion that is the life of the soul, which is the cause of all physical motions.⁷⁷ Though the discursive conscious life of the soul is not itself in time, since it is identical with time, all physical motion is in time because it is simultaneous with some stretch of time (this is illustrated by the example of a man walking, at 3.7.13, 53-66). Hence Plotinus's theory, he thinks, meets the crucial conditions for a philosophical account of time. Finally, he thinks his theory, unlike others, provides a clear analysis of the difficult concept of temporal succession. Aristotle had tied this to the ordered succession of the before and after in physical motion. But, as we have seen, Aristotle had been unable to distinguish clearly between two sorts of succession, the kinetic and the temporal (cf. 3.7.9, 56-63). Moreover, he had been left with no easy way to explain how the movement of thought could be in time, and this had apparently led some of his followers to deny that subjective or psychological time was real (cf. 3.7.13, 30-40).⁷⁸ A similar insistence that time has primarily to do with measuring physical motion has led some contemporary philosophers to speak paradoxically about the “myth of passage” and to deny the reality of subjective time. Plotinus claims that all these difficulties can be solved if we realize that psychic motion is more real than physical motion, and that the succession it contains is metaphysically the cause both of temporal succession and of the succession in physical motion.

This is a view of time that perhaps few of us will find sympathetic. Like the rest of Plotinus's metaphysics it is radically idealist. But whatever we may think of it as a philosophical theory, it should at least be admired for the care and ingenuity with which it is argued. In a rigorously dialectical manner, Plotinus examines on their own terms and independently of any presuppositions of his own all the physicalistic theories of time that were available to him, and shows that even by their own lights they are incapable of saving the phenomena of time. He then tries to show how his own view, derived from a deep and original reading of Plato, can solve the puzzles raised by all other theories. His arguments thus amount to a dialectical demonstration of his own theory, which is all he thinks is available in such matters. Plotinus's doctrines may seem odd to us, but his method is that of a true philosopher.⁷⁹

Notes

1. References to the Enneads will be to Henry and Schwyzer's editio minor. The following discussions of the treatise will be cited by the author's last name only: Werner Beierwaltes, Plotin: Über Ewigkeit und Zeit (Ennead 3.7) (Frankfurt am Main: Klostermann, 1967); Émile Bréhier, trans., Plotin: “Ennéades” 2nd ed. (Paris: Les Belles Letters, 1956), vol. 2, introduction to Ennead 3.7, pp. 123-26; G. H. Clark, “The Theory of Time in Plotinus,” Philosophical Review 54 (1944): 337-48; Karen Gloy, “Die Struktur der Zeit in Plotins Zeittheorie,” Archiv für Geschichte der Philosophie 71 (1989): 303-26; Andreas Graeser, “Zeitlichkeit und Zeitlosigkeit: Bemerkungen zu Plotins Unterscheidung zweier ‘immer’ (III.7),” Philosophisches Jahrbuch 94 (1987): pp. 142-48; Jesús Igal, trans., Plotino, “Enéadas” (Madrid: Gredos, 1982-87), vol. 1-2, and especially the general introduction (vol. 1, pp. 74-77); Hans Jonas, “Plotin über Ewigkeit und Zeit: Interpretation von Enn. III.7” in A. Dempf et al., eds., Politische Ordnung und menschliche Existenz: Festgabe für E. Voegelin (Munich: Beck, 1962), 295-319; Peter Manchester, “Time and the Soul in Plotinus, III.7 [45], 11,” Dionysius 2 (1978): 101-36; J. E. McGuire and Steven K. Strange, “An Annotated Translation of Plotinus Ennead III.7, On Eternity and Time,” Ancient Philosophy 8 (1988): 251-71; John F. Phillips, “Stoic ‘Common Notions’ in Plotinus,” Dionysisu 11 (1987): 33-52; Richard Sorabji, Time, Creation and the Continuum (Ithaca, N.Y.: Cornell, 1983), chaps. 8-10. Beierwaltes's book is a text and translation of the treatise with introduction and commentary, and Jonas's article also provides a useful paraphrase of the entire treatise. Sorabji unfortunately deals only with the doctrine of eternity.

2. The best treatment of Plotinus's methodology is Thomas A. Szlezák, Platon und Aristoteles in der Nuslehre Plotins (Basel and Stuttgart: Schwabe, 1979), chap. 1, pp. 14-51, which presents useful criticisms of previous discussions. Szlezák however commits the common error of taking Plotinus to claim only to be an interpreter of Plato (cf. n. 21 below). The same is true of Jean-Michel Charrue, Plotin: Lecteur de Platon (Paris: Les Belles Lettres, 1978); see pp. 17-18. See also Phillips, on whose discussion cf. nn. 16-18 below, and Alain Eon, “La notion plotinienne d'exégèse,” Revue internationale de philosophie 24 (1970): 252-89.

3. There has been much good work in recent years on Aristotle's methodology, but the classic treatment of Aristotle's use of the dialectical method remains G. E. L. Owen, “Tithenai ta phainomena,” in S. Mansion, ed., Aristote et les problèmes de méthode (Louvain: Presses Universitaires, 1961), reprinted in G. E. L. Owen and Martha C. Nussbaum, eds., Logic, Science and Dialectic (Ithaca: Cornell, 1986). On Aristotle's dialectical method, see also J. D. G. Evans, Aristotle's Conception of Dialectic (Cambridge: Cambridge University Press, 1977). T. H. Irwin, Aristotle's First Principles (Oxford: Clarendon, 1988), among other scholars, wishes to distinguish different types of dialectical inquiry in Aristotle. I follow the ancient commmentators in treating Aristotle's dialectic as a unitary method applicable to all areas of philosophical inquiry. In any case it sems safe to assume that Plotinus read Aristotle in this way.

4. Cf. Topics 101a35-b4, where Aristotle asserts that dialectic provides the proper way to the principles of any science. See also Metaphysics 3.1, 995a28-31.

5. Cicero in various passages (De finibus 5.10, Tusculan Disputations 2.9, De oratore 3.80) credits Aristotle with using (and even, wrongly, with inventing) the method of arguing on both sides of the given question, a clear allusion to the initial aporetic stage of Aristotelian dialectical inquiry. Cicero's focus is on this because of its similarity to the method of Academic scepticism, which was a development from the dialectical method practiced in the older Academy. The Academic sceptics were, like the Socrates of Plato's early dialogues (and the Aristotle of the Topics), more concerned with refuting theses and raising aporiai than in solving them, while it is the solution of the aporiai that makes dialectic a positive method of inquiry for Aristotle. Positive Aristotelian dialectic, however, has clear Platonic antecedents as well: consider for instance the way that the Eleatic Stranger in the Sophist solves the puzzles he has raised about being and not-being by employing the distinction between absolute and relative not-being. Note that Plotinus identifies the highest sort of dialectic with the dialectic of the Sophist (cf. Ennead 1.3.4 and 6.2).

6. It is important to notice that Plotinus assumes that his readers will be Platonists who will share his assessment of Plato as preeminent among the philosophers of the classical period: cf. Ennead 5.8.4, 54-56, where it is taken for granted that “we” will wish to be worthy of the appellation … “Platonist.” Plotinus appears to be writing for his own students, and perhaps for circulation to other noted Platonists such as Longinus (Porphyry, Life of Plotinus §§19-20), not for general publication. This accounts for his neglect in most of his treatises to defend fundamental Platonist assumptions such as the theory of Ideas.

7. The opening of Ennead 3.7.1 is very reminiscent of Augustine's remarks at Confessions 11.14 init. about the difficulty of defining time, especially “quid est ergo tempus? si nemo ex me quaerat, scio; si quaerenti explicare velim, nescio.”

8. The expression … “the ancient philosophers,” seems to have been used in an almost technical way in the Platonic tradition as early as Antiochus of Ascalon in the first half of the first century b.c. (cf. Cicero De finibus 5.23) to denote Plato, Aristotle and their contemporaries in the Old Academy. Cf. also John S. Kieffer, Galen's Institutio Logica (Baltimore: Johns Hopkins, 1964), 130-33. Porphyry at least was willing to extend it to include the early Stoics (see e.g., De Abstinentia 3.1.5), and given the contents of Ennead 3.7 Plotinus may be using it this way too. He obviously means it to include Parmenides as well.

9. Compare what Plotinus says at Ennead 2.9.10.12-14: the Gnostics “dare to disparage what ancient and divine men have spoken well and in accordance with truth”—a reference to Plato and others who had discussed the nature of intelligible reality, cf. Ennead 2.9.6, 26-28 and 37-38.

10. Plotinus, like Plutarch, speaks only of έννοιαι in this connection, cf. Robert B. Todd, “The Stoic Common Notions: A Re-examination and Reinterpretation,” Symbolae Osloenses 48 (1973): 61-62. The classic discussion of the theory of common conceptions is A. Bonhöffer, Epictet und die Stoa (Stuttgart: Enke, 1890), 188ff., which should however be compared with the criticisms of F. H. Sandbach, “Ennoia and Prolepsis in the Stoic Theory of Knowledge,” Classical Quarterly 24 (1930): 44-51; reprinted in A. A. Long, ed., Problems in Stoicism (London: Athlone, 1971). A wealth of material on the theory and its background is provided by Klaus Oehler, “Das Consensus omnium als Kriterium der Wahrheit in der antiken Philosophie und der Patristik,” Antike und Abendland 10 (1961): 103-29, and Ruth Schian, Untersuchungen über das “argumentum e consensu omnium” (Hildesheim: Olms, 1973). For Plotinus's use of common conceptions as criteria, see Phillips's article and H. J. Blumenthal, “Plotinus and Proclus on the Criterion of Truth” in Pamela Huby and Gordon Neal, eds., The Criterion of Truth: Essays Written in Honour of G. Kerferd (Liverpool: 1989). …

11. The fourth-century Neoplatonist Sallustius characterizes them as “those conceptions to which all men will assent if questioned properly” … Concerning the Gods and the Universe 1.2). Galen, On the Best Sect §2, ad fin. identifies common conceptions with what is self-evident to the mind (1.107, Kühn); cf. A. A. Long, “Ptolemy on the Criterion,” in Huby and Neal, eds., The Criterion of Truth, 161 (= J. Dillon and A. A. Long, eds., The Question of “Eclecticism” [Berkeley: California, 1988], p. 200).

12. Cf. Aristotle, Met. 993a30-994b4 and NE 1172b36-1173a1: … (“What seems so to everyone, we say is true”), and for later Greek thought, Malcolm Schofield, “Preconception, Argument, and God,” in Schofield et al., eds., Doubt and Dogmatism (Oxford: Clarendon, 1980), 294ff.

13. For Alexander's view see also R. W. Sharples, Alexander of Aphrodisias On Fate, 18. Alexander may have influenced Plotinus's adoption of Aristotle's methodology.

14. On this point, cf. Michael Frede, “Stoics and Skeptics on Clear and Distinct Impressions,” in M. F. Burnyeat, ed., The Skeptical Tradition (Berkeley: U. of California Press, 1983), 84 (= Frede, Essays in Ancient Philosophy [Minneapolis: Minnesota, 1987], 168), and Jonathan Barnes, “Aristotle and the Methods of Ethics,” Revue internationale de philosophie 34 (1980), 506-10.

15. Cf. Ennead 5.3.3, 6-9 on the xανwν or standard of goodness in the soul with Alcinous, Didaskalikos §4, 156, 19-21, Hermann. Platonists of course did not think that an empiricist account of the origin these notions could be given: cf. Cicero, Tusculan Disputations 1.57-58, Didaskalikos §25, 177.45-178.12, Hermann, and Plutarch apud Olympiodorus In Phaed. 156.1-14. All three of these passages connect common conceptions with recollection. The role of recollection in Plotinus's epistemology is somewhat controversial. H. J. Blumenthal, Plotinus' Psychology (The Hague: Nijhoff, 1971), 96-97, among other scholars, thinks that genuine Platonic recollection has been replaced in Plotinus by the notion of the undescended intelligence, so that texts which mention recollection can only be paying lip service to Plato's theory. Phillips distinguishes between a sort of recollection that deals with common conceptions (Plotinus's “imprints” … in the soul), as in Ennead 5.3.2-3, and another sort involving direct knowledge of Ideas (ibid., 1.2.4): see n. 18 below. I am unconvinced by attempts to find important differences between Plotinus's view of recollection and common conceptions and that of the tradition. In fact he seems to appropriate the traditional view as his own; this accounts for his not saying more about the subject. Plotinus's more complex psychology no doubt makes for some differences, but they should not be overemphasized.

16. Plotinus connects our preanalytic grasp of eternity and time, which presents us with the initial illusion of … clarity, with that produced by “means of more concise [or cursory] conceptual apprehensions.” …

17. Other sources speak of the process of clarifying our preconceptions as “articulation” of them: cf. Anon. In Theaet. 23.1ff., Epictetus Diss. 2.11.13-18, 2.17.5-9 (other passages in Bonhöffer, Epictet, cited in 189 n. 11 above), Plutarch, De comm. not. 1059bc …, and Porphyry, De Abst. 1.31.2 and Ad Marc. §10. Note that the Porphyry passages make clear that properly articulating conceptions is what leads to knowledge of Ideas. If this is Plotinian, as I assume it is, it would explain the connection between the two sorts of recollection noted by Phillips (see n. 16 above).

18. But Aristotle too occasionally favors the views of the philosophers over those of the many: cf. EE 1214b34-1215a4.

19. Cf. Todd, “Stoic Common Notions,” 61 (cited in n. 11 above). The use of common notions as principles in dialectic may go back to Socrates: cf. Xenophon, Memorabilia 5.6.15, where they are apparently referred to as … “the things most of all agreed upon.”

20. But it should be clear from his gibe at Longinus in Life of Plotinus §14 that he does not see himself merely as such. It is wrong to take the famous passage at Ennead 5.1.8.10-14 as a claim to be merely an exegete of Plato; Plotinus is only claiming there that the doctrine of the three hypostases is implicit in Plato (see my review of M. J. Atkinson, Plotinus's Ennead 5.1: On the Three Principal Hypostases in Philosophical Review 95 [1986]: 101). At Ennead 6.2.1, 4-5 and 6.2.3, 1-2 it is said to be a condition upon the inquiry that what we say should agree with Plato (compare Plutarch, De An. Proc. 1013b, where the criterion, following Eudorus, is said to be plausibility … and agreement with Plato).

21. Cf. David Sedley, “Philosophical Allegiance in the Ancient World,” in Miriam Griffin and Jonathan Barnes, eds., Philosophia Togata (Oxford: Clarendon, 1989), 102-03. Sedley's article is extremely illuminating on the notion of belonging to an ancient “school” of philosophy. Against the widespread view of Plotinus as a dogmatist, see R. Ferwerda, “L'incertitude dans la philosophie de Plotin,” Mnemosyne 33 (1980); 119-27.

22. On this “circle of justification” in Plotinus's method, see also Eon, La notion plotinienne, 263 (cited in n. 2). Compare Plotinus's attitude toward Plato with the Stoics' reverence for Socrates: according to them, he if anyone had made progress toward wisdom (Diogenes Laertius 7.91); cf. also A. A. Long, “Socrates in Hellenistic Philosophy,” Classical Quarterly 38 (1988): 150-51.

23. Plotinus criticizes Parmenides and Aristotle in Ennead 5.1.8-9 for their disagreements with Plato's view of the nature of the intelligible world.

24. See especially Ennead 3.7.11, 45-62, where Plotinus makes the correspondence between the properties of eternity and time explicit. The characteristics of time reflect those of eternity because time is derived from eternity.

25. Cf. for example Ennead 6.2.22, 36-38.

26. Sorabji, chaps. 8-9.

27. Boethius is indebted to Plotinus's discussion of eternity particularly for his notion of the nontemporal uses of “now” … and “always” … This is not to imply that Boethius has read Ennead 3.7; he seems rather to be dependent on some work deriving from it. Plotinus, for instance, would never countenance speaking of the spatium of eternal life, as does Boethius (loc. cit.) See n. 45 below, on E. Stump and N. Kretzmann's conflation of the views of eternity of Boethius and Plotinus. This is an area where work remains to be done.

28. This follows from his understanding of the paradigm-image relation. Surprisingly, it is implied by Beierwaltes (pp. 214-15, perhaps under the influence of Aquinas, Summa Theol. 1a10.1 resp. init.), that according to Plotinus one can only know an image by first coming to know the corresponding original. But Plotinus in fact denies this (Ennead 3.7.1, 20-24), saying that it would be possible also to investigate the nature of the original by first investigating its image, then passing to consideration of the original by a method he calls … recollection. Beierwaltes seems to think that if one were to proceed by the latter method one would not come to know the image before understanding the original, since to know it is to know its cause. (See Beierwaltes p. 149 for his comment on Ennead 3.7.1, 16-24.) However Platonic this argument may seem, I doubt it is Plotinian, and it is certainly not present in the text: cf. Ennead 3.7.1, 21-22, which speaks of contemplating the essence of time … before contemplating eternity. Bréhier's introduction to the treatise (p. 123) curiously exhibits the opposite mistake of thinking that Plotinus holds that one can only come to know a paradigm through its image. The issue is more adequately discussed by Jonas, pp. 295-96 and 311-12; see also Phillips, p. 46.

29. See the table of correspondences between Plotinus's language in Ennead 3.7.3-6 and that of Parmenides B8 given by Beierwaltes (p. 178) which however is not complete. Chapter 3 of the treatise in particular concerns the timelessness of Being of Parmenides B8.

30. On this point, cf. Andre-Jean Festugière, “Le sens philosophique du mot AIΩN,” La parola del passato 11 (1949): 172-89, reprinted in his Études de philosophie grecque (Paris: Vrin, 1971).

31. Contrast Bréhier, p. 125, who assumes that Plotinus is here dealing with actual predecessors' views.

32. Plotinus is careful later to specify precise senses of the terms “eternity” and “eternal” in an attempt to make this condition come out true: the fundamental property is that of eternality … which is predicated of the intelligible world as a whole (as are beauty and truth, Ennead 3.7.4, 7-12), while “eternity” denotes this property taken together with its subject, like Aristotle's examples of “snubness” and “snub” in the Metaphysics (Ennead 3.7.5.15-18; cf. 3.1-3).

33. The same proposal is considered in Ennead 4.4.15, lines 8-11 and rejected in Ennead 4.4.16. For this view of Plato's thought in the Timaeus, see G. E. L. Owen, “Plato and Parmenides on the Timeless Present,” The Monist 50 (1966), reprinted in his Logic, Science and Dialectic (cited in n. 3 above); and John Whittaker, “The ‘Eternity’ of the Platonic Forms,” Phronesis 13 (1968): 131-44. For criticisms of this view see Leonardo Tarán, “Perpetual Duration and Atemporal Eternity in Parmenides and Plato,” The Monist 62 (1979): 43-53, and especially Richard Patterson, “On the Eternality of the Platonic Forms,” Archiv für Geschichte der Philosophie 67 (1985): 27-46. In all essentials I accept Whittaker's view of the passage: the key point is that Plato sees existing in time as coextensive with undergoing change, and in fact considers existing in time to involve undergoing a change, namely becoming older (“becoming older and younger than oneself”; Tim. 38a2-5). Hence something will have eternal existence if and only if it is eternally unchanging in all respects. The weakest aspect of this interpretation is that it does not adequately account for Plato's remark that eternity “remains in unity,” condition (2) in my text, and it is not surprising that Plotinus places particular stress on this condition in laying out his stronger interpretation of the Timaeus passage.

34. Festugière, “Le sens philosophique,” 183 (cited in n. 32 above), claims that the answer is provided by the fact that for Plato the Ideas are by definition unchanging essences, i.e., they are distinguished from sensibles precisely by being fixed, not in flux. He is perhaps right that this is Plato's answer, but it depends crucially on this particular way of making the Ideas-sensibles distinction, a way that is notoriously fraught with difficulties, and which I do not think that Plotinus would want to endorse. But Plotinus, because his conception of eternity is stronger than Plato's, has available to him the better answer that I present in the text. Cf. also Patterson, “On the Eternality,” 36 (cited in n. 35 above), and Aristotle Met. 1088b23-24. An interpretation of Plotinus's motives similar to mine is given by Igal, “Introducción general” (pp. 74-75).

35. Intelligible reality is completely partless, yet somehow contains a multiplicity: see, e.g., Ennead 2.4.4, 11-12. … The multiplicity affirmed by Plotinus of the intelligible world is to be identified with the multiplicity of its constituents. Cf. the following note.

36. His first line of argument, leading up to the initial characterization of eternity in §3, draws upon (c) and (d), and appears to be an argument by elimination (cf. also McGuire and Strange, p. 252). Eternity, as a feature of the intelligible world as a whole, must have some connection with the … constituents of that world (note that Ennead 3.7 immediately follows in the chronological order of Plotinus's writings the treatise on categories, 5.1-3, which contains his most detailed discussion of these “categories of the intelligible”). …

37. An allusion to Parmenides B8.5. …

38. Ennead 1.5.7, 23 adds the Parmenidean phrase “neither more nor less” (cf. Parmenides B8.44-45), glossing this as the claim that it is measured by no interval. This is connected with the complete partlessness of intelligible reality, which is nevertheless somehow divisible (cf. n. 38 above).

39. No such conception need be attributed either to Parmenides or to Plato; cf. Whittaker, “Eternity” (cited in n. 35 above), and Sorabji, pp. 98-112. It had however been found in them before Plotinus: cf. e.g., Plutarch De E §20 init. and Whittaker, “Ammonius on the Delphic E,” Classical Quarterly n.s. 19 (1969): 185-92.

40. Cf. also Ennead 4.4.1.15. … Jonathan Barnes offers a similar interpretation of Paramenides' notion of the timeless now, based on a reading of B8.19-20 which resembles Plotinus's: see his The Presocratic Philosophers, 2nd ed. (London: Routledge and Kegan Paul, 1982), 193-94; cf. Ennead 3.7.3.27-34. Barnes insists, however, that Parmenides' vuv must be taken as a temporal moment, though one stripped of any connection with past and future. Plotinus would not agree: see below on his non-temporal sense of “now.” (Note that Barnes thinks that such a conception of the eternal now is internally coherent.) Plotinus's forerunner Numenius, like Barnes's Parmenides, conceives of eternity as an eternal temporal present (fr. 5.6-9, Des Places). Plotinus clearly means to reject Numenius's view: cf. Dominic J. O'Meara, “Being in Numenius and Plotinus: Some Points of Comparison,” Phronesis 21 (1976): 128 n. 5.

41. Cf. Aquinas Summa Theol. 1a10.1 resp. 2. Cf. also William Kneale, “Time and Eternity in Theology,” Proceedings of the Aristotelian Society n.s. vol. 61 (1960-61): 87-108; Graeser, p. 142 n. 3; and Eleanor Stump and Norman Kretzmann, “Eternity,” Journal of Philosophy 78 (1981): 429-58. For similar reasons, Pierre Aubenque, “Plotin philosophe de la temporalité,” Diotima 4 (1976): 83, denies that Plotinus conceives of eternity as timeless at all, but rather as sempiternal or everlasting, a view rightly rejected by Graeser (loc. cit.). Stump and Kretzmann interpret the classical notion of eternal life as a totum simul found in Boethius, which they take to be the same as Plotinus's conception, as what they call a “timeless duration,” which though a duration contains no order or succession of events, and every portion of which is present to every other. Whether or not this represents Boethius's conception, it is certainly not Plotinus's, whose claim that eternity is completely … (unextended) is clearly intended to exclude any sort of duration. Stump and Kretzmann note Plotinus's use of the term … (p. 431 n. 6), but remark that since “in the rest of Enneads III.7 … Plotinus goes on to derive duration from his definition [of eternity],” that it is not to be taken seriously. But this claim cannot be supported from Plotinus's text, nor do they attempt to do so. (On this point cf. Sorabji, p. 113.) In addition, their interpretation seems to miss a key step in Plotinus's argument: the unextendedness of eternal life is supposed to follow directly from the complete co-presence of that life to itself, which is just the denial of real distinction of parts within it, which any sort of duration, if this is to be more than an empty word, must possess. (For further elucidation of the details of their view, see Paul Fitzgerald, “Stump and Kretzmann on Time and Eternity,” Journal of Philosophy 82 (1985): 296-73, and their “Reply to Fitzgerald,” Journal of Philosophy 84 (1987): pp. 214-20.) Stump and Kretzmann are unwilling to grant that a notion of nondurational eternal life is coherent, because they think that the concept of life necessarily involves that of duraction (p. 446). But this seems just to be a confusion resulting from reimporting temporal concepts into the notion of eternal life, as if the eternal now to be part of a life must have a future. …

42. This accusation is made by A. H. Armstrong, “Eternity, Life and Movement in Plotinus's Accounts of Nοûs,” in Le néoplatonisme: Colloques internationaux du Centre National de la Recherche Scientifique (Royaumont, 9-13 juin 1969) (Paris: CRNS, 1971), 69-74 (cf. Sorabji, p. 114); see also H. J. Blumenthal “Nous and Soul in Plotinus: Some Problems of Demarcation,” in Plotino e il Neoplatonismo in Oriente e in Occidente, Accademia Nazionale dei Lincei, Problemi attuali di scienza e di cultura, no. 198 (Rome: Accademie Nazionale dei Lincei, 1974), 203-19. On the problem posed by Plotinus's occasional talk of potency in the intelligible world, see Smith, “Potentiality” (cited in n. 37 above), and Ennead 6.8.1, 11-13, where Plotinus explicitly recognizes the difficulty.

43. Cf. Ennead 6.1.16, 14-15 …

44. Cf. above, n. 44, on Barnes's interpretation of Parmenides B8.5.

45. For the two senses of άεί, see also Ennead 3.7.2, 28-29 and 5.8.12, 17 (where the “always” of time is said to be an image of the “always” of eternity), and Graeser's article.

46. Plutarch attributes to Pythagoras the view that time is the World Soul, the cause of celestial motion (Platonic Questions 1007b; this is the sense, whatever the text). Plotinus knows nothing of this attribution. “Aetius” and Simplicius think the identification of time with the sphere of the outer heaven mentioned by Aristotle is Pythagorean: cf. Ross's remarks on Physics 4.10.218b1.

47. On being ‘in time’ as occupying time or being subject to measurement by it, cf. Physics 4.12.221a13-18 and a26-b23.

48. Aristotle endorses this view at Physics 4.14.222b30-31.

49. Certainly Plotinus knew and often worked from Alexander's commentaries, among others, as Porphyry informs us in Life 14.10-14. Moreover, Ennead 3.7.10.12-13 seems to contain a reference to Alexander as “he who says [time] is the measure of the motion of the All” (see n. 58 below on Alexander's interpretation). It is more likely that Plotinus is here using Alexander's commentary on the Physics than his brief treatise On Time, which is extant in Arabic and Latin versions. An English translation of this work by F. M. Zimmermann is presented and discussed by R. W. Sharples, “Alexander of Aphrodisias On Time,” Phronesis 27 (1982): 58-81. On the distinction between this work and Alexander's commentary on the Physics, see pp. 67-68.

50. Strato of Lampsacus (apud Simplicius, In Phys. 789.2-9; cf. Simplicius In Cat. 346.14ff. and 351.4-8 [I owe the latter references to R. W. Sharples]) objected that since time is a continuous quantity and recognized as such by Aristotle, that he should have stuck to calling it a measure instead of a number, which is a sort of discrete quantity. Plotinus agrees with this criticism: see Ennead 3.7.9, 12 and 17-31. Aristotle perhaps calls time a number because he has in mind the account of time in Plato's Timaeus, where time is a motion that proceeds according to number.

51. Cf. Ennead 3.7.9, 31-34, where, following Aristotle (Physics 8.6.260a17-19), Plotinus identifies the primary uniform motion with that of the outer heavenly sphere, but ignores the problem of how we can even know that any motion is regular or uniform, i.e., proceeding at a constant rate, without some independent measure of time. Aristotle is aware of this difficulty: cf. Edward Hussey, Aristotle's Physics Books III and IV (Oxford: Clarendon, 1983), 174.

52. Cf. Alexander, On Time, chap. 10 (Sharples, “Alexander,” 64; cited in n. 55 above), but there is no reason why he could not have said this in the Physics commentary as well. As Sharples notes (p. 69), Alexander bases this interpretation on Physics 4.14.223b18-20. The same view is proposed by Fred D. Miller, Jr., “Aristotle on the Reality of Time,” Archiv für Geschichte der Philosophie 56 (1974): 136.

53. Though it is the solar, not the sidereal day that is commonly used as the basic unit of time measurement, probably because it is the one that most obviously suggests itself to our senses. (Cf. Tim. 46e-47a.)

54. So also Hussey, Aristotle's Physics, 151 and 176ff. (cited in n. 57 above). The latter usage is quite natural in ancient Greek, and we too can speak of a “number” of persons. For this same distinction in Plotinus, cf. Ennead 6.1.3, 25-27 and 6.6.16, 2. It is perhaps this distinction that Strato had in mind in insisting against Theophrastus that time is a measure that is essential to motion, not accidental to it (Simplicius In Cat. 346.14ff.).

55. Cf. Sharples, “Alexander,” 79 n. 45 (cited in n. 55 above).

56. In light of the theory of relativity, this might be seen to be a virtue of Aristotle's account, but the fact remains that he wants to defend the thesis that one and the same time is simultaneously present everywhere, because this is what everyone believed.

57. Sarah Waterlow [Broadie], “Aristotle's Now,” Philosophical Quarterly 34 (1982): 111, tries to defend Aristotle on this point by defining what she calls a ‘when’ as “a point of temporal coincidence” between items or nows in the successions of different simultaneous motions. ‘Whens’ would thus be equivalence classes of nows. But I fail to see that Aristotle's official theory leaves him with any noncircular way of defining the notion of temporal coincidence.

58. Cf. Hussey, Aristotle's Physics, p. 160, ad 220b5.

59. See A. C. Lloyd, Form and Universal in Aristotle (Liverpool: Francis Cairns, 1981), 55ff.

60. On Aristotle's inconsistencies on this point, see G. E. L. Owen, “Aristotle on Time,” in Peter Machamer and Robert Turnbull, eds., Motion and Time, Space and Matter (Columbus: Ohio State University Press, 1976), 23 (= Owen, Logic, Science and Dialectic, 313, cited in n. 3 above).

61. Physics 4.11.219a33-35 perhaps shows that this is not as far from Aristotle's thought as Sharples thinks it is (Sharples, “Alexander,” 69; cited in n. 55). Cf. Gloy, pp. 303-04: “Aristoteles Theorie ist nicht verständlich ohne die Unterscheidung eines an sich seienden Substrats der Zeit, das sich an der Bewegung findet, und einer Explikation und Definition der Zeit, die auf das Konto der zählenden Seele geht.”

62. Plotinus seems to have taken this argument from Galen: cf. n. 82 below.

63. This argument only shows that soul is a necessary condition for the existence of time. However, Plotinus takes the Peripatetics to have already conceded that time is independent of physical motion.

64. See below, p. 51, on Plotinus's ultimate assessment of Aristotle's view at Ennead 3.7.13, 9-18.

65. Cf. Ennead 5.3.6, 14-16 on the … quietude of unfallen soul as it exists in intellect.

66. This translation … is taken from Clark, p. 350.

67. On the syntax of line 14, cf. Manchester, p. 117 n. 41, and McGuire and Strange, n. 102.

68. Cf. especially the reference to newly fallen souls delighting in their new-found autonomy … at Ennead 5.1.1, 5, as well as the other parallel passages on the fall of the soul collected by Jonas, pp. 315-17. …

69. Cf. Ennead 3.7.13, 43 with, e.g., 4.3.12, 28. In the earlier treatise, 4.3-4, Plotinus describes the conscious life of undescended soul as not involving discursive thought: he is driven to do so by his eschatology and his conception of the eternal bliss of the divine cosmic souls. Undescended soul nevertheless differs from intellect in retaining the potential for thinking discursively (4.4.1). The distinction of soul and intellect as what thinks discursively or step by step as opposed to what thinks everything at once is fundamental to Neoplatonism. This fact is only highlighted by Proclus's innovation of recognizing a higher level of soul capable of thinking some but not all forms at once (Marinus, Life of Proclus §27, init.).

70. For this doctrine, see the first few chapters of Ennead 3.8. The earlier Ennead 4.4.17 gives an apparently different account of the source of discursion and temporal succession in terms of the practical need for incarnate soul to focus on different intentional objects. This seems inconsistent with the account of 3.7.11 in that it presupposes the existence of the physical universe.

71. Cf. Tim. 37-38 with Plotinus Ennead 4.4.15, 11-14; Igal, “Introducción general,” 76-77. Igal proposes to reconcile these texts by identifying time not with the activity of discursive thought but with the outer activity of the lower aspect of the World Soul. This however would fail to account for all rational souls sharing one and the same time, which is one of Plotinus's main concerns in the treatise (see below on Ennead 3.7.13, 66-69). Igal also raises a further difficulty concerning Plotinus's view on whether souls are located in time in the way physical things are. Ennead 4.4.15, 11ff. seems to suggest that our souls are “in a way” in time, while the position of 3.7.11 (a later treatise) is that no soul is in time, since soul produces time. But note that the time-producing soul of Ennead 3.7.11, 30 is said to ‘temporalize’ itself. … The last passage of Ennead 3.7.13 (53ff.) is precisely a discussion of why Plotinus's theory does not entail that the soul is strictly in time: cf. 4.4.15 fin., where the same view is upheld.

72. So Jonas, pp. 309-10, n. 17; cf. McGuire and Strange, n. 103.

73. On the unity of soul doctrine, cf. H. J. Blumenthal, “Soul, World-Soul, and Individual Soul in Plotinus,” in Le néoplatonisme, 55-63 (cited in n. 46 above). I do not think, however, that the doctrine is as dangerously incoherent as Blumenthal appears to suggest. Part of the difficulty in Blumenthal's account of the matter comes from failing to distinguish the lower soul which informs bodies, and which is not really individual for Plotinus, since it is an emanation from the World Soul, from what Plotinus often calls “our” soul, i.e., the rational soul, which is individual and distinct from the lower soul. The appeal to the doctrine in Ennead 3.7 shows its importance for Plotinus; it also plays an important role in his theory of participation in Ennead 6.4-5.

74. Roland Teske, “The World-Soul and Time in St. Augustine,” Augustinian Studies 14 (1983): 75-92, has seen the fundamental importance of the doctrine of the unity of souls for Plotinus's theory of time, as well as well as its influence on Augustine's view of time in Confessions 11. Contrast Gloy, p. 304, who thinks Plotinus's doctrine is that the World Soul, not individual soul, is the generator of time, and that the crucial difference from Augustine's “subjectivist” view lies in this point.

75. This argument is certainly not original with Plotinus, for it is opposed by Alexander in On Time §5. It seems originally to be due to Galen: cf. Sharples, “Alexander,” 72-78 (cited in n. 55 above) and Simplicius, In Phys. 708.27 ff.

76. See J. D. Mabbott, “Our Direct Experience of Time,” Mind 60 (1951), reprinted in part in Richard Gale, ed., The Philosophy of Time: A Collection of Essays (New Jersey: Humanities Press, 1968), 304-21.

77. This is of course the doctrine of Phaedrus 245-46 and of Laws 10.

78. Cf. McGuire and Strange, p. 270 n. 124.

79. Versions of this paper were read at the University of Texas at Austin, Princeton University, Duke University, to the ancient philosophy seminar at The University of Chicago, and at Georgetown University, as well as at the Catholic University of America. I am grateful to the audiences on those occasions, and to Ted McGuire and Ian Mueller, for their help, and particularly to Tom Beauchamp, Bill Blattner, and R. W. Sharples for written comments.