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A PLATONIC ARGUMENT FOR THE IMMORTALITY OF THE SOUL IN CICERO (TVSCVLANAE DISPVTATIONES 1.39–49)

Published online by Cambridge University Press:  14 April 2023

Matthew Watton*
Affiliation:
University of Toronto
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Abstract

An argument in Cicero's Tusculan Disputations (Tusc. 1.39–49) defends psychic immortality by reference to the physical constitution of the soul. This article argues that this ‘Physical Argument’ should be interpreted as a reception of Plato's doctrine of the soul within the philosophical paradigm of the Hellenistic era. After analysing the argument, it is shown that Cicero's proof recasts elements of Plato's Phaedo, in particular the kinship between the soul and the heavens and the soul's essentially contemplative nature, within a corporealist cosmology. The article also argues that Cicero formulates his argument to oppose the Stoic view that the soul's survival after death is only temporary. The Physical Argument emerges as a modernization of Platonic thought, putting Plato into dialogue with contemporary Hellenistic philosophy. Cicero, too, emerges as a more adept philosophical author than is often supposed.

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Research Article
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The first book of Cicero's Tusculan Disputations (= Tusc.) is a riff on the ancient genre of consolation literature. Whereas some consolatory works aim to relieve the bereaved after the loss of a loved one, Cicero here aims to dissuade his interlocutor from his own fear of death (Tusc. 1.9).Footnote 1 Early on in the discussion, the question of the value of death gives way to a discussion of the nature of the soul: is the soul mortal or immortal? The work achieves its consolatory aim by working through this dilemma: either the soul is mortal or it is immortal; either way, death is not an evil. If the soul is mortal, then there exists no subject who would experience the evil of death. If the soul is immortal, then death is in fact a boon, and an eternal blissful life awaits.Footnote 2

While the philosophical works of Cicero's late period (46–44 b.c.e.) are predominantly concerned with expounding and opposing the doctrines of the Hellenistic schools, this would not do for psychic immortality. In Hellenistic philosophy, the dominant sects were unanimous about the mortality of the soul: the Epicureans held that psychic atoms dissipate at death; the Stoics that, while some or all souls survive separation from the body, their permanence is ultimately temporary and they too will perish.Footnote 3 Instead, Cicero credits the defence of the immortality of the soul to Plato (Tusc. 1.39, 1.49). Cicero offers some version of the Platonic doctrine of immortality in a number of works, most famously in the Somnium Scipionis,Footnote 4 and the arguments of Tusc. Book 1 have a degree of overlap with these other discussions.Footnote 5 Yet the exposition in Tusc. Book 1 is unique in the way in which it deploys these proofs and integrates the Platonic arguments into its specific dialogic and argumentative framework.Footnote 6 For these reasons Tusc. Book 1 deserves a deeper examination than it has yet received. Tusc. Book 1 has been largely overlooked by all but the most dedicated source-critics, determined to find traces of Posidonius or Antiochus lurking behind Cicero's text.Footnote 7 Moving beyond the source-question gives us a better appreciation of the unique argumentation of Tusc. Book 1, and thus a pivotal moment in the ancient reception and interpretation of Plato. (NB: I will refer to the author of the dialogue as ‘Cicero’, and to Cicero's dialogic avatar as ‘Marcus’.)Footnote 8

Cicero presents Tusc. Book 1 as a companion piece to two Platonic works, the Apology and the Phaedo: the former provides the sceptical argumentative framework, while the latter is the locus classicus for Plato's defence of immortality.Footnote 9 In this article I set aside Cicero's Academic-sceptical perspective and mode of composition.Footnote 10 I focus instead on one particularly puzzling argument, which I call the ‘Physical Argument’ (Tusc. 1.39–49). The argument is puzzling for at least two reasons. First, it appears to attribute to Plato the doctrine that the soul is a corporeal substance with an elemental constitution, an attribution at which most interpreters of Plato, both modern and ancient, would likely demur. Second, the argument appears patently Stoic—Marcus mentions Panaetius by name (1.42)—while none the less arguing for the Platonic and un-Stoic conclusion of psychic immortality. I defend two claims in response to these apparent incongruities. First, the Physical Argument can be defensibly grounded in a reading of Plato, above all the Phaedo, within the theoretical milieu of the Late Hellenistic era. Second, the dialectical thrust of the argument is anti-Stoic: Marcus’ strategy is to argue that the Stoics, in light of their own philosophical commitments, ought to agree with Plato's doctrine of psychic immortality. In these ways the Physical Argument presents a modernization of Plato by bringing Platonic doctrine to bear on contemporary Hellenistic debates about the nature of the soul. By situating this argument within a contemporary dialectical context, the dialogue's return to Plato also marks the return of Plato to the philosophical fray.

I. A LATIN PHAEDO

Within the fictional narrative of the dialogue, the discussion is prompted by Marcus’ young interlocutor's, ‘A.’, fear of death (malum mihi uidetur esse mors, 1.9). Since death is either the separation of soul and body or the complete dissolution of the soul (1.18), the value of death and whether it is to be feared hinges on the nature of the soul. In his first pass, Marcus mounts a Socratic or elenctic refutation of the claim that death is an evil (1.9–18).Footnote 11 A. is unpersuaded, partly because he resists Marcus’ logical hair-splitting but more so because of his unshakeable attraction to immortality. A. signals this to Marcus, and in doing so Cicero signals to his readers the prominence of Plato in the discussion to come:

A. … in the first place I want this view [that we survive after death] to be so, and even if not, nevertheless I want to be persuaded.

M. So why do you need my work? Surely I can't surpass Plato in eloquence. Carefully read through that book of his, the one on the soul (qui est de animo):Footnote 12 you'll want for nothing more.

A. Dammit! I've done this, and many times over. But somehow, while I'm reading it I give my assent, but when I put down the book and by myself begin to contemplate the immortality of souls, all my former assent slips away. … Explain then, if you don't mind, first, if you can, that souls remain after death; then, if you fall short of establishing this (for it's difficult), please teach that death lacks all evil. For I fear this very thing, that it is an evil, and I don't mean that to lack sensation [is an evil], but the necessary prospect of lacking it. (24–6)Footnote 13

A.'s request sets the template for the dialogue that follows, and Marcus will treat each horn of the dilemma—the soul is either immortal or mortal—in turn. The exchange also makes clear the importance of Plato, above all the Phaedo, in defending the first horn of the dilemma.Footnote 14 The Phaedo is in many ways the Ur-consolatory text,Footnote 15 and Marcus’ discussion directly and indirectly refers to the Phaedo throughout.Footnote 16 But why does Cicero make A. a reader of the Phaedo? GildenhardFootnote 17 has identified here Cicero's spirit of cross-cultural rivalry: where Plato has failed to persuade, Marcus will succeed. But this overlooks the fact that Cicero presents Marcus as recasting Plato's own arguments for psychic immortality. This suggests that Tusc. Book 1 does not so much aim to supplant the Phaedo as to reframe and update Plato's arguments in a way that will be persuasive and effective for Cicero's contemporary audience.

Marcus’ three Platonic arguments are:

  1. (i) Physical Argument (39–49)

  2. (ii) Affinity Argument (50–70)

  3. (iii) Simplex Argument (71)

It is fairly straightforward to discern the Platonic provenance of Arguments (ii) and (iii). In (ii), Marcus defends the immortality of the soul by likening it to god (Tusc. 1.50–1, 66, 70), recasting the Affinity Argument of the Phaedo (79e8–80a5).Footnote 18 In (iii), Marcus offers an embellished translation of Socrates’ claim that the soul is non-composite (Tusc. 1.71 ~ Phd. 78c1–4). But the sense in which (i), the Physical Argument, can be considered Platonic is far less obvious.

II. THE PHYSICAL ARGUMENT

In the Physical Argument, Marcus argues for the immortality of the soul based on the soul's elemental constitution: the physical make-up of the soul guarantees its immortality. In this section, I offer an exegesis of the Physical Argument before situating it within its dialectical and interpretative context.

While Marcus attributes some of the cosmological details of the Physical Argument to certain mathematici (40), Cicero marks the proof as Platonic. Just as in 24–6, again Cicero dramatically motivates the introduction of Plato through A.'s Platonic fervour: A. would rather err with Plato than believe the truth with anyone else (39); Marcus approves of his enthusiasm (40).Footnote 19 While the doctrine that souls are immortal was first advanced by Pherecydes and his pupil Pythagoras, the Pythagoreans failed to give reasoned argument (rationem illi sententiae suae non fere reddebant, 38–9).Footnote 20 It is Plato who, having studied in Italy with Pythagoreans, was the ‘first not only to believe in the immortality of souls but also to adduce arguments as well’ (primumque de animorum aeternitate non solum sensisse … sed rationem etiam attulisse, 39; cf. 49). The contrast is not merely between Platonic argument and Pythagorean authority (cf. Nat. D. 1.10). Indeed, Marcus asserts that, even if Plato had offered no proof, he would be compelled by Plato's authority alone (ut enim rationem Plato nullam adferret … ipsa auctoritate me frangeret, 49). Thankfully, this is not the case: Plato has offered rational arguments for the immortality of the soul (tot autem rationes attulit, 49). Dramatically, then, Cicero draws us away from both A.'s blind adoration of Plato and Plato's weighty authority to an appreciation of Platonic argument itself.

I now turn to the details of the Physical Argument. Marcus begins by stating some cosmological facts: earth is the centre of the universe, which is composed of four elements with natural motions each towards its natural place, earth and water downwards, air and fire upwards (40). The upward motion of these latter elements is due either to their inherent nature or else because of their lightness. These cosmological facts teach us about the soul:

(T1) Since these are agreed upon, it should be clear that souls, when they depart from the body, whether they are breathy, that is, of an airy nature, or fiery, are carried aloft. But if the soul is some sort of number (a view more subtle than lucid), or some fifth thing, unnamed but understood, then there are things even more pure and uncontaminated that carry themselves as far as possible from the earth. Therefore, the soul <is> one of these, so that so active a mind does not lie submerged in the heart, brain, or Empedoclean blood. (40–1)Footnote 21

Marcus here does not advocate a single theory of the constitution of the soul but asserts a range of possible views: whether it is fiery–air, or quinta essentia, or even number, the nature of the soul carries it upwards. Why these three views? I suggest they all share two things in common.

First, these three candidates all originate in the thought of Plato's successors, at least according to the history of the Academy taught by Cicero's teacher Antiochus of Ascalon. Antiochus had claimed that Plato's successors in the Old Academy, the Peripatos and the Stoa all take their start from Plato himself, and are in broad agreement despite some minor doctrinal differences.Footnote 22 The constitution of the soul is one such difference (Acad. 1.26, 39; Fin. 4.12–14). Aristotle advocates quinta essentia (Tusc. 1.22, 65–6 = Cons. fr. 21 Vitelli; Acad. 1.26; Fin. 4.12), Xenocrates number (Tusc. 1.20; Acad. 1.39; Luc. 124), and Zeno fire (Tusc. 1.19; Acad. 1.39; Fin. 4.12; Nat. D. 2.41). So, according to a prominent historical account of the Academy, all three views about the constitution of the soul have their roots in Plato's thought.

Second, the underlying thought behind these three views is that the soul's physical constitution must be sufficient to account for the activity of soul, which is treated as identical to mens (cf. Tusc. 1.22, 46, 66, 67, 70). Marcus here calls the mind uegeta, a word connoting specifically mental activity; later, the soul's swiftness is emphasized (43).Footnote 23 Thus, the constituent element(s) of the essentially active soul must itself be essentially active. The active nature of the mind is supposed to be sufficient evidence that soul is not to be identified with blood, the heart, or the brain. In both Stoic physics (SVF 2.418, 444) and the physics Antiochus attributes to the Old Academy (Acad. 1.26), fire and air are the active elements, and the Stoics emphasized the essential activity of fire (Nat. D. 2.41). Similarly, Cicero writes that Aristotle opted for quinta essentia because of the active nature of the mind (Tusc. 1.22, 65–6).

Xenocratean number is obviously the odd one out, as is reflected in Marcus’ apparent puzzlement (‘a view more subtle than lucid’).Footnote 24 In the earlier doxographical section, Marcus states that Xenocrates denied that the soul has any shape or corporeality but is composed of number, ‘since number had the greatest power (uis) in nature’ (1.20).Footnote 25 So Xenocrates too attributed to souls a composition that is essentially active. Marcus’ incomprehension seems to arise from two considerations. First, all of Cicero's reports of Xenocrates’ definition of the soul omit the claim that the soul is a self-moving number (ἀριθμὸν αὑτὸν κινοῦντα, Aët. Placita 4.2.1; see frr. 85–107 IP2). This omission, it seems to me, derives from a more fundamental philosophical problem with the view for Cicero, namely the incorporeality of number. On Antiochus’ account, Zeno rejected Xenocrates’ definition because only bodies can be causally active (Acad. 1.39); Cicero echoes this in his sceptical doxography on the nature of the soul (Luc. 124).Footnote 26 I suggest, then, that Xenocrates’ view is deemed ‘too subtle’ because it is unclear in what way number, even if it were an active force, can possibly account for the psychic activity of the soul. The soul must act and be causally efficacious, and in Cicero's Hellenistic milieu causal action requires corporeality. This in turn indicates that Marcus’ conception of the soul in the Physical Argument as essentially active correlates with the fact that he conceives of the soul as something material.

In the next stage of the argument Marcus reiterates the consequence of the elemental theory of the soul:

(T2) Now if the soul is of one of the four elements out of which everything is said to be made, it is made from heated air, as I think seems most commendable to Panaetius. By necessity it strives for higher regions, for these two elements have no share of the lower and always seek the higher. Therefore, if these elements are dispersed, this happens far from the earth, but if they remain and preserve their proper condition, it is even more necessary that they are carried towards the heavens. (42)Footnote 27

Marcus names Panaetius as advocate of the Stoic theory that the soul is made of pneuma. I will return to Panaetius in section IV below, but note here that the Stoic theory is none the less stipulated conditionally—if it is one of the four elements, it is fiery breath; this retains the possibility of Aristotle, or even (though less likely) Xenocrates, being right.

T2 highlights that the elemental argument leaves the conclusion underdetermined: there remain two live possible conclusions, namely that either the soul survives dissociation with the body but later dissolves or it remains forever (ita, siue dissipantur, procul a terris id euenit, siue permanent et conseruant habitum suum).Footnote 28 The latter is the Platonic conclusion of psychic immortality for which Marcus is arguing. The former is the Stoic view that all souls survive separation from the body, but do not persist eternally (cf. Tusc. 1.77–8).Footnote 29 So far then, the elemental argument can support either a Stoic or a Platonic conclusion, and it remains for the argument to defend psychic immortality over Stoic temporary permanence. That is what Marcus goes on to do:

(T3) When the soul reaches this region and is in contact with and recognizes a nature similar to itself, it settles among the fires composed from rarefied air and the tempered heat of the sun and ceases from its upward ascent. For when it has reached a heat and lightness similar to itself, held aloft in equilibrium no part of it moves, and at long last, when it penetrates to what is similar to itself, this is its natural seat. Here it lacks nothing and is nourished and sustained by the same things which nourish and sustain the stars. And since we are accustomed to be burned by the fires of the body and we are spurred towards nearly every desire … certainly we will be happy, when we are free from desire and jealousy with our bodies left behind. (43–4)Footnote 30

The soul's post-mortem permanence—rather than its belated dissolution—is defended by reference to the cosmological theory of natural place in conjunction with a particular moral psychology. When in the heavens, the soul is surrounded only by what is of the same nature as itself (sui simile). It is thereby devoid of destructive alien bodily influences and consequently free from anything that would cause its dissolution. Among what is akin to itself, it will cease its motion and be nourished by the same nourishment as the stars. So far, this is an argument from physics that could apply as much to fiery souls as to elemental fire. Marcus supplements this with a conception of the affections of the soul: since the soul is corrupted by emotion while embodied, when divorced from the body it will be free from these somatic corruptions. This emphasis on the freedom from bodily desire and emotion fits with the broader aims of the Tusculan Disputations, throughout which Cicero defends a broadly Stoic ideal of the extirpation of all emotions. Here, the freedom from psychic disturbance is not just the aim of human ethical pursuits, but the very fact that this is desirable while embodied is further proof that the soul will survive eternally intact after death. By combining the physical argument about the natural place of the corporeal soul with a moral psychology which emphasizes freedom from psychic disturbance, Marcus drives home the Platonic conclusion that the soul is immortal and rules out the Stoic alternative that disembodied souls only persist for a limited time in the heavens.

The proof ends with an elaboration of the activities in which the immortal soul will engage when disembodied:

(T4) What we do now when we are free from concerns, how we desire to look upon and examine things, we will do this even more freely then and will dedicate ourselves entirely to contemplation and understanding, especially because in our minds there is a natural insatiable desire to see the truth. To the extent that the borders of the regions to which we migrate makes this knowledge of the heavens easier to attain, so much greater will our desire for understanding be. This beauty, even on earth, excites that paternal and ancestral philosophy (as Theophrastus says), which is inflamed by a desire for thought. But theirs will be the highest enjoyment who, even while inhabiting this earth and engulfed in darkness, nevertheless desired to pierce through. (44–5)Footnote 31

The human soul, Marcus claims, has a natural desire to see the truth. Since when embodied we turn to contemplation when we are free of earthly concerns (cum laxati curis sumus), all the more will the disembodied soul devote itself wholly to contemplation and investigation (totosque nos in contemplandis rebus perspiciendisque ponemus). While embodied we are limited, but when disembodied we will be able to attain a panoptic vision of the entire earth, its inhabitants and the heavens (45–7). Marcus adds a brief supplement on the mechanisms of the perceptive and cognitive powers of the soul (46): against a possible objection that the disembodied soul will be unable to perceive and contemplate without sense-organs, Marcus argues that ‘there is no perception in the body’ (neque est ullus sensus in corpore) but that the soul itself perceives through the sense-organs (animum et uidere et audire).Footnote 32 The argument closes with a brief litotes: Marcus could continue to enumerate the marvellous sights and discoveries that await the soul in its natural abode (quam multa, quam uaria, quanta spectacula animus in locis caelestibus esset habiturus, 47), but this would go too far astray from the essential point of the soul's immortality.

So goes the Physical Argument. Marcus has not offered a complete account of the life cycle of the soul—for instance, he does not discuss how souls become embodied in the first place.Footnote 33 In line with the narrower consolatory aims of the dialogue, the focus is on eschatology and securing the soul's post-mortem permanence in the celestial realm.

III. A HELLENISTIC PLATO

The Physical Argument is proof for psychic immortality grounded in the physics and cosmology of the Late Hellenistic era. But while it comes to the same conclusion as Plato, in what sense can the argument itself be considered ‘Platonic’? Many of the details will strike readers as patently Stoic. We are left to wonder how Cicero could have believed that this kind of argument could be plausibly associated with Platonic immortality. I propose a two-part explanation. First, in Cicero's intellectual milieu, the fundamental approach of Stoic physics had become associated with the Platonic tradition as well. Second, once we realize the ubiquity of these shared commitments, we are able to read the Physical Argument as emerging from an interpretation of Plato's Phaedo within this contemporary paradigm.

Stoics held that the soul, god and the heavenly bodies are all made of pneuma or fire, and that human souls are fragments (ἀποσπάσματα) of god and so share the same pneumatic physical constitution.Footnote 34 Yet we have seen that Marcus does not solely report Stoic views (T1) but draws on the broader Platonic tradition, including Aristotle and the Pythagoreans. Within Cicero's milieu, a view similar to that of the Stoics had become common property among these schools. The Aristotelian notion of quintessence—largely absent from Aristotle, and surely not the physical constituent of the soul for him—rises to prominence among late Hellenistic Peripatetics.Footnote 35 Similarly the Pythagoreans are said to hold that souls are ἀποσπάσματα of aether (Alexander Polyhistor apud Diog. Laert. 8.28), and that our souls are ‘plucked’ (carperentur) from the all-pervasive world soul (Cic. Nat. D. 1.27). Relevant too is Antiochus’ conception of Old Academic philosophy. Antiochus claimed that the physical nature of the soul was a point of contention within the Old Academic tradition (Acad. 1.39; Fin. 4.12), but that by-and-large the Stoics and the Academics are in agreement about the most important aspects of physics (de maxima autem re eodem modo, Fin. 4.12). While Antiochus’ own position on the physical nature of the soul remains obscure,Footnote 36 his account of the physics of the Old Academic tradition are reflective of the broader trends in Cicero's philosophical milieu.Footnote 37 The predominance of a view of this kind is clear from Cicero's other expositions on the nature of the soul. For example, in the Somnium Scipionis the soul is composed of the same eternal fires as the heavenly bodies (Rep. 6.15).Footnote 38 We see, then, the ubiquity of the doctrine of a divine corporeal soul even within the Platonic tradition. What the Physical Argument does is argue from the physical constitution of the soul to its immortality. By framing this as a Platonic proof, Cicero brings Plato into the fold of Hellenistic thought about the nature of the soul.

Yet we would still like to find some sort of justification that renders the Physical Argument more than a mere retrojection of Hellenistic physics onto Plato. I think that, given this philosophical milieu and the ubiquity of the theory of a corporeal soul, the Physical Argument emerges as the result of an attentive reading of the nature of the soul in Plato's own works, in particular the Phaedo. To see this, let us look at two passages from the Phaedo which have close affinities to the Physical Argument:

(T5) But whenever the soul engages in investigation, itself by itself, it ventures there into what is pure and always existing and immortal and self-same. The soul, since it is akin to this, is always with this whenever it comes to be itself by itself and is able to be this way. And it ceases from its wandering and is in the same state with respect to the same things, because it grasps things of this nature. And is this condition of the soul not called wisdom? (Phd. 79d1–7)Footnote 39

(T6) The soul of the philosopher would reason in this way: it would not think that philosophy must free it, but nevertheless, once free, give itself over to pleasure and pains and bind itself down once again, working to no end like Penelope at her loom. Instead, the soul achieves a calm from these emotions, and follows reason and is always in reason, contemplating what is true and divine and removed from opinion. Nourished by this, it thinks that it ought to live in this way as long as it is alive, and when it dies, it will arrive at what is akin and of this nature and be freed from human evils. From this nourishment, Simmias and Cebes, there is no danger that one should fear that in separating from the body the soul would be dispersed by winds, blown apart and strewn about, ceasing to be anything anywhere. (Phd. 84a2–b7)Footnote 40

Socrates here recounts the nature of the soul, wisdom and the life pursued by the philosopher. I identify six key parallels with Marcus’ Physical Argument.

  1. (1) The soul is naturally akin to the divine and heavenly. In the Phaedo, the soul is akin (συγγενής, 79d3; 84b2) to the eternal and the divine, and will arrive at and grasp (ἐφαπτομένη, 79d6) what is akin to itself after death (cf. 81a4–10).Footnote 41 Marcus states that the disembodied soul will rise to its natural seat (naturalis est sedes) in the heavens, where it will ‘be in contact with and recognize a nature similar to itself’ (animus naturamque sui similem contigit et adgnouit, 1.43 [T3]).

  2. (2) The soul ceases its motion in the heaven (πέπαυταί τε τοῦ πλάνου, 79d4–5; finem altius se ecferendi facit, Tusc. 1.43 [T3]).Footnote 42

  3. (3) The soul is nourished in the heavens. For Socrates, this nourishment (τρεφομένη, τροφή) is achieved in contemplation.Footnote 43 Marcus claims that the ascended soul will be ‘nourished and sustained’ by the same things which nourish the heavenly bodies (T3). As a cosmological doctrine, this resembles the Stoic view that stellar bodies are nourished by the vapours from the earth (Diog. Laert. 7.145, Cic. Nat. D. 2.40). But note that Marcus here conspicuously does not identify the nourishment of souls and stars.

  4. (4) For Socrates and Marcus, the soul's ascent requires release from desires and affections. At 81a–c, Socrates describes the soul's pollution by desires as being weighed down by the bodily and earthly, and so restricted from its ascent to the heavens.Footnote 44 As in the Phaedo, Marcus seems to identify the source of these pernicious desires with the body itself (corporis facibus, Tusc. 1.44; cf. Phd. 66b–e). Additionally, Marcus follows Socrates in employing the soul's freedom from desire as proof of its immortality. Socrates assures Simmias and Cebes that the nourishing effects of contemplation ensure the likelihood that the soul will not be ‘dispersed by winds’ (T6). Similarly, Marcus argues that the freedom from destructive affections ensures that the soul (qua elemental compound) will not be dispersed (dissipantur, 42 [T2]) far from earth but will remain intact. Here the Physical Argument mirrors not only the doctrinal content but also the argument itself.

  5. (5) The disembodied soul will engage in perpetual contemplation.Footnote 45 This is because contemplation is the natural activity of the soul. Socrates asserts that what the soul does ‘itself by itself’ is its proper or natural activity (T5). Marcus follows suit and identifies contemplation as the activity of the soul on its own, without the need for body (46).Footnote 46 And just like Socrates (Phd. 114c), Marcus too demurs at explaining in full detail the soul's post-mortem life of contemplation (Tusc. 1.47).

  6. (6) Both Socrates and Marcus insist that, even while embodied, humans should pursue this life of contemplation. For Socrates, this is what it means for the life of the philosopher to be practice for death (Phd. 67d8–9). Marcus later repeats Socrates’ sentiment (tota philosophorum uita … commentatio mortis, 1.74), and emphasizes that those who have separated their souls from the body through contemplation in life will have an easier ascent to the heavens (1.44–5 [T4]; cf. 75).

Cicero has fashioned Marcus’ argument with an eye to Plato's Phaedo. The significance of this lies in the fact that Marcus does not merely rehearse Socrates’ arguments. Rather, he integrates Socrates’ views on the essence of the soul into a cosmological argument about the physical nature of the soul. The Physical Argument transmutes the themes and features of Plato's text into the realm of Hellenistic physics and cosmology and situates this Platonic argument in the contemporary philosophical paradigm of the Late Hellenistic era.

IV. THE ANTI-STOICISM OF THE PHYSICAL ARGUMENT

I have argued that, despite its apparent Stoic features, the Physical Argument can plausibly be viewed as a refiguring of arguments from the Phaedo, ‘modernized’ for Cicero's contemporary audience. What would be the philosophical motivation for undertaking such an interpretation of Plato? One option would be to invoke Plato in support of Stoic philosophy. Panaetius is named explicitly in the argument (T2), and scholars have noted significant parallels with a Stoic theological argument found in Sextus Empiricus (Math. 9.71–4 = SVF 2.812).Footnote 47 We might suspect that the affinities between the Physical Argument and Stoic thought are a product of the supposed Stoic ‘rapprochement’ with Plato in the Late Hellenistic era.Footnote 48 But there are good reasons to resist this conclusion. Quite the opposite: I claim that the dialectical core of the argument is anti-Stoic, designed specifically to counter the Stoic account of the post-mortem impermanence of the soul.

We must first get clear on the Stoic alternative to Platonic immortality. Among those who take death to be the separation of soul and body, Marcus distinguishes three options (Tusc. 1.18): (i) the soul immediately disintegrates upon separation; (ii) the soul temporarily survives intact but eventually suffers dissolution; (iii) the soul remains forever. The first is the Epicurean view, the third the Platonic view, and the second the Stoic view (cf. 1.77).Footnote 49 But one might accuse Cicero of oversimplifying here, as the Stoic view is not univocal. While Zeno is reported to have claimed that the soul is long-lasting but mortal,Footnote 50 his successors disagreed on the extent of the soul's post-mortem survival. Diogenes Laertius (7.157 = SVF 2.811) reports that ‘Cleanthes holds that all souls continue to persist until the conflagration, while Chrysippus holds that it is only the souls of the wise that do.’Footnote 51 The Chrysippean view dominates later doxography.Footnote 52 Two further Stoic positions are relevant. Panaetius, although he denied the conflagration, none the less adhered to the line that rejects the immortality of souls.Footnote 53 Finally, Posidonius’ view on immortality has been a point of contention for interpreters, since he apparently claimed that ‘the air is full of immortal souls’ (plenus aer sit inmortalium animorum, Cic. Diu. 1.64 = fr. 108 EK). I follow the interpretation offered by Ju, who contends that for Posidonius souls are immortal (ἀθάνατος) in so far as they survive death (that is, the separation from the body), but are nevertheless perishable (φθαρτός) and so liable to dissolution: souls therefore will dissipate during (if not before) the conflagration, and it is only god or the world soul who can be declared both immortal and unperishing (ἄφθαρτoς).Footnote 54

Tusc. Book 1 completely fails to distinguish between these Stoic views. In particular, there is no mention of the different status granted to wise and non-wise souls, and any reference to the conflagration is conspicuously absent. That said, I do not think that Cicero's broad-brush approach seriously undermines his critical engagement with the Stoics. All these Stoic views agree in denying the eternity of souls and everlasting immortality to individuals. Given this underlying unity, I think it is justifiable for Cicero to paper over the details of the various accounts. The Stoics themselves admit that wisdom is vanishingly rare; since nearly every soul is non-wise, the special dispensation Chrysippus grants to the souls of the wise is moot.Footnote 55 In turn, this might justify the absence of the conflagration, since in practice the vast majority of souls will perish well before the conflagration.Footnote 56 In fact, one factor (but certainly not the only one) in specifically targeting Panaetius’ objections to immortality (1.79–80) may be that Panaetius is an example of a Stoic who denies the immortality of the soul on grounds irrespective of Stoic cosmological theory. Finally, it seems likely that Cicero, if he is sensitive to Posidonius’ distinction between immortal and unperishing, ultimately rejects this distinction.Footnote 57 The central conception of immortality in Tusc. Book 1 identifies immortality and eternity (aeternitas, 1.39, 50, 55, 80, 81), that is, eternal temporal permanence (1.18 permanare … semper; cf. 77 Stoici … semper negant). This identification is exactly what is denied by Posidonius’ distinction.Footnote 58 For these reasons, then, I think that Cicero is justified in treating the Stoic position monolithically as committed to the temporary permanence but ultimate destruction of the soul after death.

We can now return to the Physical Argument. Recall that at 1.42 (T2), Marcus teases the possibility of the Stoic conclusion only to resolutely deny it: the soul may persist temporarily only to dissipate later, but the natural affinity between the soul and the heavenly bodies and the soul's freedom from bodily disturbance prove that this cannot be so (T3). The implication of suggesting the Stoic theory only to deny it is that the Stoics themselves are guilty of the following error: their own theory of the physical nature of the soul and the cosmos is sufficient proof of the immortality of the soul, but they erroneously conclude that souls are subject to dissolution at some time after death. The Stoics by their own lights should agree with Plato but fail to do so.

This is exactly the criticism Marcus and A. raise against the Stoics later on. In maintaining that the soul persists after leaving the body, the Stoics assent to the most difficult part of the argument (quod tota in hac causa difficillimum est, Tusc. 1.78). But in asserting that souls nevertheless perish, they err in denying the logical consequence (quod … consequens) of their own view (Tusc. 1.78). Marcus then returns to Panaetius in order to draw the connection between this objection to Stoic psychology and the Stoic rejection of Plato:

Are we to believe Panaetius, when he dissents from his beloved Plato? For everywhere he calls Plato divine, wisest and most revered, the Homer of philosophers, but he does not abide by this one belief about the immortality of the soul. … He adduces a second argument: there is nothing that feels pain that is not also susceptible to sickness; but whatever succumbs to disease will also succumb to death; souls feel pain; therefore, they die as well. [80] These can be refuted: for they show his ignorance that, when the discussion is about the eternity of souls, we mean ‘mind’, which is always free from all disturbing motion, not the other parts [of the soul], which are subject to pains, angers and desires, which [Plato], against whom [Panaetius] is arguing, thinks are removed and isolated from the mind. (1.79–80)Footnote 59

Marcus mentions two objections to immortality levelled by Panaetius; my interest is in Marcus’ response to the second objection.Footnote 60 Marcus invokes Plato's tripartition of the soul, alluding to the theory of the Timaeus and the Republic that only the rational part of the soul is immortal.Footnote 61 In the doxographical section, Marcus had already identified Plato's tripartite theory of the soul (Tusc. 1.20),Footnote 62 and the proofs of immortality have focussed on the soul qua mens, that is, the rational soul. Since the rational soul is distinct from its irrational parts, it will be free from the destructive forces of pain and desire, and will survive permanently after its separation from the body. This reiterates the argument for the soul's eternal survival rather than merely temporary permanence advanced in the Physical Argument (T3).

Marcus’ response to Panaetius reinforces the anti-Stoic thrust of the Physical Argument. Recall that the broader argumentative aim of the dialogue is to demonstrate that, whatever the nature of the soul, death is not an evil. In principle, the mortality of the soul could serve this therapeutic goal, and indeed Marcus will go on to deploy a mélange of arguments concerning psychic mortality (82–111). The Stoic position alone is targeted for explicit refutation and is thereby flagged as especially deserving of reproach. The problem is that the Stoic position cannot convince us that death is not an evil because it is logically untenable. And it is untenable precisely because it does not agree with the necessary Platonic conclusion of immortality.

Panaetius, of all Stoics, is a fitting target for Marcus. The objections are not original to Panaetius,Footnote 63 but rather Panaetius is named as a representative of the broader Stoic position, as in T2 above. Panaetius had garnered a particular reputation as an ardent φιλοπλάτων, a Platonophile, as Philodemus calls him (T1 Alesse, Ind. St. LXI).Footnote 64 Here Marcus tells us that Panaetius calls Plato ‘divine, wisest and most revered, the Homer of philosophers’ (Tusc. 1.79), and elsewhere we learn that Panaetius ‘always had the names Plato, Aristotle, Xenocrates, Theophrastus and Dicaearchus on his lips’ (Fin. 4.79). By adhering to Stoic orthodoxy on the mortality of the soul, Panaetius is emblematic of the inconsistency which the Physical Argument imputes to all Stoics, rejecting Platonic immortality in spite of their own doctrines.Footnote 65

It is enticing to connect Marcus’ refutation of Panaetius with the reports that Panaetius labelled Plato's Phaedo inauthentic (νοθεῦσαι; frr. 146–8 Alesse). The details are obscure, but it is likely that Panaetius meant that the central thesis of the Phaedo—the immortality of the soul—was not a genuine Platonic view.Footnote 66 Marcus’ reproach turns the tables. Panaetius’ denial of the immortality of the soul becomes a mark not only of his philosophical ignorance but also of his misunderstanding his beloved Plato. I suggest that Marcus’ objection to the Stoics can be seen as a further intertextual nod to the Phaedo. Panaetius occupies the same philosophical position in Tusc. Book 1 as Cebes had in Plato's dialogue. Cebes’ famous ‘cloak maker’ objection protests that Socrates’ arguments prove only that the soul is long-lasting (πολυχρόνιον), not that it is immortal (Phd. 87b–88b). The long-lastingness of the soul is exactly the Stoic position (Stoici … diu mansuros aiunt animos, semper negant, Tusc. 1.77).Footnote 67 Cebes is a Pythagorean, and his incredulity at the immortality of the soul signals his inability to adhere to Pythagorean doctrine; he needs Socrates to convince him of his own doctrine, as it were.Footnote 68 So too here Panaetius, according to Marcus, ought to believe in the immortality of the soul both as a lover of Plato and as a Stoic. As Socrates corrects Cebes, so Marcus corrects Panaetius, and the Stoics in general, about their aberrance from Plato and the proper interpretation of their own doctrines.

V. CICERO'S PLATO

I have argued that the Physical Argument in Tusc. Book 1 is Platonic: Cicero presents a modern version of Plato, interpreted in light of, and in response to, the dominant philosophical paradigm of the Late Hellenistic era. This brings Plato into dialogue with contemporary philosophy, and in particular takes aim at the Stoics for their dissension from Plato. Marcus’ anti-Stoic strategy anticipates one that will recur in many of the Middle Platonists of the Imperial period: Marcus at once evokes Stoic doctrine only to undermine it by subordinating the incomplete and inadequate approach of the Stoics to a fuller and more consistent Platonic theory.Footnote 69 But there is a crucial difference between the Physical Argument and the strategies of later Platonists: Tusc. Book 1 does not advance the notion of an immaterial soul, but rather counters the Stoics within the Stoics’ own framework of psychic corporealism.Footnote 70

Finally, I have sidelined the source-question in order to give the Ciceronian material itself a fair shake. I do not wish to rehash the arguments pro et contra Posidonius or Antiochus or whoever as the source behind Tusc. Book 1.Footnote 71 In fact, it seems to me that the source-question places the burden of proof in the wrong place, in so far as it assumes that Cicero needed a source. The dramatic unity of Marcus’ speech, especially his singling out of Panaetius (1.42; 79–80) and his advocacy for the life of contemplation (1.44–7; 74–5), speaks to Cicero's originality in crafting the argument. And the close parallels between the Physical Argument and the Phaedo suggest that, if we are so compelled to find a single source behind Cicero's argument, our best bet is to identify it as Plato himself. Tusc. Book 1 is a creative reinterpretation of Plato, and the Physical Argument has adapted and repurposed elements of the Phaedo to engage in the Hellenistic debate about the nature of the soul. Cicero, it seems to me, is the perfect candidate for this kind of creative reception of Platonic doctrine. Cicero was a product of his age, and he has presented a reading of Plato as a Hellenistic philosopher would. But being a student of one's age is different from being a slavish expositor of one's predecessors and I believe, barring any definitive evidence to the contrary, that the assumption should be one of Cicero's originality as a philosophical author.

Footnotes

I would like to thank George Boys-Stones for his comments, advice and encouragement, the attendees of the 2019 St Andrews Graduate Conference in Ancient Philosophy for their feedback, and James Allen and Rachel Barney for early discussions on various issues relating to this piece.

References

1 The first book is explicitly consolatory (leuatio, 1.119; consolatio, 1.111; cf. Att. 15.2.4 = 379 SB); Cicero later describes its subject as de contemnenda morte (Diu. 2.2). Consolation or therapy is one of the aims of the Tusc. as a whole (3.1–7, 75–6; 5.121).

2 The dilemma is found at 1.23 (cf. 26, 118) and provides the macrostructure of the dialogue as a whole (immortality defended: 1.26–81; mortality defended: 1.82–111). On the structure of Tusc. Book 1, cf. Gildenhard, I., Paideia Romana: Cicero's Tusculan Disputations (Cambridge, 2007), 224–47Google Scholar.

3 Epicureans: Ep. Hdt. 65–6; RS 2; Lucr. 3.417–829. Stoics: texts at SVF 2.809–22, discussed in section IV below.

4 Rep. 6.9–29. Elsewhere at Leg. fr. 1; Consol. frr. 21–3 Vitelli; Hortens. frr. 114–15 Grilli; Tusc. 1.26–77; Sen. 77–8; Amic. 13–14. Cic. Leg. 2.68 refers to Plato's discussion of immortality at Pl. Leg. 959a–b, but does not pursue it. See also Scaur. 4–5.

5 P. Corssen, De Posidonio Rhodio M. Tulli Ciceronis in libro I. Tusc. Disp. et in Somnio Scipionis auctore (Bonn, 1878), 41–2 charts a number of parallels between the Tusc. and the Somnium Scipionis. In Sen. 77–8, Cato offers four arguments for immortality, attributed to the Pythagoreans and Socrates in the Phaedo and recorded by Plato: (1) the activities and powers of the soul (cf. Tusc. 1.50–70); (2) the soul's eternal motion (cf. Tusc. 1.53–5 = Rep. 6.27–9 ~ Phdr. 245c); (3) the simplicity of the soul (cf. Tusc. 1.71–5 ~ Phd. 78a); (4) recollection (cf. Tusc. 1.57–8).

6 For example, in the De senectute proof (1), powers of the soul, is distinct from (4), recollection of things learned before birth. In Tusc. 1.57–8, recollection is one example among others of the cognitive powers of the soul.

7 A few recent exceptions: Gildenhard (n. 2), 207–55; C. Brittain, ‘Self-knowledge in Cicero and Augustine (De Trinitate X, 5, 7 – 10, 16)’, in G. Catapano and B. Cillerai (edd.), Augustine of Hippo's De Trinitate and its Fortune in Medieval Philosophy = Medioevo 27 (Padova, 2012), 107–36; Woolf, R., Cicero. The Philosophy of a Roman Sceptic (London, 2015), 206–11CrossRefGoogle Scholar; Long, A., Death and Immortality in Ancient Philosophy (Cambridge, 2019), 105–15CrossRefGoogle Scholar; Wynne, J.P.F., ‘Cicero on the soul's sensation of itself: Tusculans 1.49–76’, in Inwood, B. and Warren, J. (edd.), Body and Soul in Hellenistic Philosophy (Cambridge, 2020), 199230CrossRefGoogle Scholar. Disagreement on sources dominates earlier literature. Posidonius as source: Corssen (n. 5); Pohlenz, M., De Ciceronis Tusculanis disputationibus (Gottingen, 1909)Google Scholar. Antiochus: K. Reinhardt, ‘Poseidonios von Apameia’, RE XXII.1 (1954), cols. 558–826, at 575–86; Luck, G., ‘Studia diuina in uita humana: on Cicero's “Dream of Scipio” and its place in Graeco-Roman philosophy’, HThR 49 (1956), 207–18Google Scholar. Crantor: Dougan, T.W., M. Tulli Ciceronis, Tusculanarum Disputationum libri quinque (Cambridge, 1905), xx–xxivGoogle Scholar. Philo of Larissa: R. Hirzel, Untersuchungen zu Ciceros philosophischen Schriften, vol. 3 (Leipzig, 1883), 404–5. J. Dillon, The Middle Platonists: A Study of Platonism, 80 b.c. to a.d. 220 (London, 19962), 101 cannot decide between Antiochus, Posidonius, or Cicero himself. Jones, R.M., ‘Posidonius and Cicero's Tusculan Disputations i.17–81’, CPh 18 (1923), 202–28Google Scholar stands out among earlier scholars in crediting Cicero with originality.

8 Labelled ‘M.’ in our manuscripts, but easily identified as Marcus (e.g. Tusc. 1.38, 53, 66; 5.32–3). On the labels of the interlocutors, see Pohlenz, M., ‘Die personenbezeichnungen in Ciceros Tusculanen’, Hermes 46 (1911), 627–9Google Scholar; Gildenhard (n. 2), 21–34.

9 Socrates’ distinction in the Apology between death as a state without sensation or a blessed afterlife (Ap. 40c; cf. 29a, 37b) provides the argumentative superstructure of Tusc. Book 1. Cicero's translation of Ap. 40c8–42a5 at Tusc. 1.97–9 indicates his debt to the Apology; see M. Watton, ‘Cicero, Socrates, and the fear of death’, Mnemosyne AoP (2022), 1–24. On Tusc. Book 1 and Phaedo, see below.

10 On scepticism in the Tusc., see W. Görler, ‘Zum literarischen charakter und zur struktur der Tusculanae Disputationes’, in Görler, W., Kleine Schriften zur hellenistisch-römischen Philosophie (Leiden, 2006), 212–39Google Scholar; Wynne, J.P.F., ‘Cicero's Tusculan Disputations: a sceptical reading’, OSAPh 58 (2020), 205–38Google Scholar; Woolf (n. 7), 201–2; Long (n. 7), 105–15 (on Tusc. Book 1 specifically).

11 On the section, see Gildenhard (n. 2), 207–27; J. Warren, ‘The harm of death in Cicero's first Tusculan Disputation’, in J.S. Taylor (ed.), The Metaphysics of Death (Oxford, 2013), 44–70.

12 Or is it ‘the De animo’? Cicero never explicitly names the dialogue as Phaedo in Tusc. Book 1, but I wonder if the words qui est de animo could be a reference to the dialogue's second title, Peri Psychēs (see Diog. Laert. 3.58; ps.-Pl. Ep. 13, 363a7). Callimachus’ Cleombrotus epigram (Ep. 23 Pfeiffer = 53 G–P = Anth. Pal. 7.471) already uses this title, and Cicero refers to the epigram at Tusc. 1.84 (but only mentions the Platonis libro). At Scaur. 4, Cicero designates the Phaedo as Plato's librum de morte. Elsewhere, he refers to the dialogue as Plato's record of Socrates’ final day (Nat. D. 3.82; Sen. 78). (Ovid [Ib. 494] will later call the dialogue De nece.) On the Platonic double titles, see R.G. Hoerber, ‘Thrasylus’ Platonic canon and the double titles’, Phronesis 2 (1957), 10–20.

13 A.idque primum ita esse uelim, deinde, etiamsi non sit, mihi persuaderi tamen uelim.

M. quid tibi ergo opera nostra opus est? num eloquentia Platonem superare possumus? euolue diligenter eius eum librum, qui est de animo: amplius quod desideres nihil erit.

A. feci me hercule et quidem saepius; sed nescio quo modo, dum lego, adsentior, cum posui librum et mecum ipse de inmortalitate animorum coepi cogitare, adsensio omnis illa elabitur. … [26] expone igitur, nisi molestum est, primum, si potes, animos remanere post mortem, tum, si minus id obtinebisest enim arduum—, docebis carere omni malo mortem. ego enim istuc ipsum uereor ne malum sit non dico carere sensu, sed carendum esse. All translations are my own. Text follows M. Pohlenz, Tusculanarum Disputationum libri V (Stuttgart, 1957).

14 Tusc. Book 1 is also teeming with references, quotations and translations, and allusions to other works of Plato: 1.52 ~ Alc. 1, 129a–32c; 1.53–5 ~ Phdr. 245c; 1.57 ~ Meno 82b; 1.63 ~ Ti. 38c–40b; 1.64 ~ Ti. 47b.

15 On philosophical consolation, see Kassell, R., Untersuchungen zur griechischen und römischen Konsolationsliteratur (Munich, 1958)Google Scholar; Redonet, R. Lillo, Palabras contra el dolor: la consolación filosofica latina de Cicerón a Frontón (Madrid, 2001)Google Scholar; Osorio, P., ‘Reconstructing BrutusDe uirtute: consolation and Antiochean fundamentalism’, Phronesis 66 (2021), 5283CrossRefGoogle Scholar.

16 Cf. Gildenhard (n. 2), 244–5; Brittain (n. 7), 110–11 with n. 9; Long (n. 7), 101, 107–8; Stull, W., ‘Reading the Phaedo in Tusculan Disputations 1’, CPh 107 (2012), 3852Google Scholar. Direct references to Phaedo: Tusc. 1.24–6; recollection (Tusc. 1.58; Phd. 72e); simplicity of soul (Tusc. 1.71; Phd. 79e); swan song (Tusc. 1.73; Phd. 84e); difficulties of enquiry (Tusc. 1.73; Phd. 85d, 99d); philosophy as preparation for death (Tusc. 1.74; Phd. 67d); Crito and Socrates’ corpse (Tusc. 1.103; Phd. 115c); harmony theory of the soul (Tusc. 1.19–20; Phd. 86a, 93a). Indirect resonances include the centrality of doxography on the soul (Tusc. 1.19–22; Phd. 96b) and Plato's relationship to Pythagoreanism (1.38–9, 49); on Pythagoreanism in the Phaedo, see D. Sedley, ‘The dramatis personae of Plato's Phaedo’, in T.J. Smiley (ed.), Philosophical Dialogues: Plato, Hume and Wittgenstein (Oxford, 1995), 1–26.

17 Gildenhard (n. 2), 245.

18 For analysis, see Brittain (n. 7), 110–19; on the similarity with Plato's ‘Affinity Argument’, cf. Long (n. 7), 109–10. We find a similar argument briefly at Rep. 6.26; see Josserand, C., ‘L’âme-Dieu. À propos d'un passage du “Songe de Scipion”’, AC 4 (1935), 141–52Google Scholar. For a different reading of the Platonic tenor of arguments (ii) and (iii), see Wynne (n. 7).

19 Gildenhard (n. 2), 253 detects a hint of irony in Marcus’ response; cf. Luc. 9.

20 Cicero connects immortality with Pythagoreans and Plato's Phaedo elsewhere (Scaur. 4–5; Sen. 77–8).

21 quae cum constent, perspicuum debet esse animos, cum e corpore excesserint, siue illi sint animales, id est spirabiles, siue ignei, sublime ferri. [41] si uero aut numerus quidam sit animus, quod subtiliter magis quam dilucide dicitur, aut quinta illa non nominata magis quam non intellecta natura, multo etiam integriora ac puriora sunt, ut a terra longissime se ecferant. horum igitur aliquid animus <est>, ne tam uegeta mens aut in corde cerebroue aut in Empedocleo sanguine demersa iaceat. (MS Bς has est, defended by Dougan [n. 7], ad loc.; Pohlenz [n. 13], ad loc. suggests putetur.)

22 Antiochus claimed that the Old Academy, Peripatetics and Stoics agreed in rebus but disagreed in uerbis; see Luc. 15; Acad. 1.17, 37, 43. Antiochus primarily highlighted agreement in ethics (Leg. 1.38, 53–5; Fin. 4.21, 72–4; 5.7, 14, 21, 74, 88–9), but noted the broad similarities in physics (Acad. 1.24–9, 39; Fin. 4.12–14). Nat. D. 1.16 seems to indicate that Antiochus extended this agreement to theology, although Balbus’ dismissive response focusses only on ethics. On Antiochus, see Sedley, D. (ed.), The Philosophy of Antiochus (Cambridge, 2012)CrossRefGoogle Scholar.

23 OLD s.v. uegeta 2. Hirzel (n. 7), 356 interestingly suggests that these three views are united by the affinity of the soul with god and the heavenly bodies. It seems to me that the material affinity between soul and god is necessitated by the more fundamental affinity in their nature, which is essentially active and rational.

24 Tusc. 1.41 quod subtiliter magis quam dilucide dicitur; cf. Luc. 124 … ut Xenocrates [that is, animus sit] numerus nullo corpore, quod intellegi quale sit uix potest.

25 Cf. Acad. 1.39; Luc. 124.

26 Cf. Fin. 4.36, where Marcus says that the soul is a kind of body, since he again finds the concept of an immaterial soul unintelligible (cum praesertim ipse quoque animus non inane nescio quid sitneque enim id possum intellegere—, sed in quodam genere corporis).

27 is autem animus, qui, si est horum quattuor generum, ex quibus omnia constare dicuntur, ex inflammata anima constat, ut potissimum uideri uideo Panaetio, superiora capessat necesse est. nihil enim habent haec duo genera proni et supera semper petunt. ita, siue dissipantur, procul a terris id euenit, siue permanent et conseruant habitum suum, hoc etiam magis necesse est ferantur ad caelum

28 To be precise, the subject of the plural verbs is the constituent active elements of the soul (haec duo genera); the idea is that the soul qua elemental compound either disperses or persists intact.

29 See 1.18 and section IV below. Dougan (n. 7), 57 thinks that the argument is Stoic and so misreads the second clause as meaning ‘until the ἐκπύρωσις’.

30 quam regionem cum superauit animus naturamque sui similem contigit et adgnouit, iunctis ex anima tenui et ex ardore solis temperato ignibus insistit et finem altius se ecferendi facit. cum enim sui similem et leuitatem et calorem adeptus <est>, tamquam paribus examinatus ponderibus nullam in partem mouetur, eaque ei demum naturalis est sedes, cum ad sui simile penetrauit; in quo nulla re egens aletur et sustentabitur isdem rebus, quibus astra sustentantur et aluntur. [44] cumque corporis facibus inflammari soleamus ad omnis fere cupiditates eoque magis incendi, … profecto beati erimus, cum corporibus relictis et cupiditatum et aemulationum erimus expertes.

31 quodque nunc facimus, cum laxati curis sumus, ut spectare aliquid uelimus et uisere, id multo tum faciemus liberius totosque nos in contemplandis rebus perspiciendisque ponemus, propterea quod et natura inest in mentibus nostris insatiabilis quaedam cupiditas ueri uidendi et orae ipsae locorum illorum, quo peruenerimus, quo faciliorem nobis cognitionem rerum caelestium, eo maiorem cognoscendi cupiditatem dabant. [45] haec enim pulchritudo etiam in terris ‘patritam’ illam et ‘auitam’, ut ait Theophrastus, philosophiam cognitionis cupiditate incensam excitauit. praecipue uero fruentur ea, qui tum etiam, cum has terras incolentes circumfusi erant caligine, tamen acie mentis dispicere cupiebant.

32 Two pieces of evidence are adduced for this claim. First, that there are occasions when, although the sense organs are unimpaired, perception and understanding are impeded by mental activity or sickness. Second is the notion of common sense.

33 If this is a Platonic argument, we might expect that souls are reincarnated. But Tusc. Book 1 has little to say about reincarnation save for an oblique reference in the brief discussion of Platonic anamnēsis: apparently our souls ‘bring knowledge with it’ to the body (cognita attulit, Tusc. 1.58; cf. 118). But it is not clear how we should connect this passage, which identifies Platonic Forms as the conceptual objects of thought (1.57–8), with our current passage, where the disembodied soul contemplates the celestial and mundane realms rather than the Forms. Even if Marcus does countenance reincarnation, it is still puzzling how the soul will become embodied in the first place, since it would be contrary to its nature to descend from the heavenly realm. Perhaps Cicero's Platonic answer would be that embodiment is caused by the gods for some purpose: Sen. 77 asserts that the gods have ‘sown immortal souls into human bodies to be the observers of the earth, to contemplate the order of the heavens and to imitate that order in their harmonious mode of life’.

34 See e.g. Diog. Laert. 7.142–3 (attributed to Posidonius); cf. 156; Nemesius, Nat. Hom. 2 (= SVF 2.773); Aët. Placita 4.3.3 (= SVF 2.779); Epict. Diss. 1.14.6, 2.8.11; M. Aur. Med. 2.1, 5.27.1, 12.26.

35 It is found in Critolaus, frr. 15–17 Wehrli and in Hellenistic doxographies (Tusc. 1.22; Philo, De somn. 1.30); Xenarchus composed a work Against the Fifth Substance (Simpl. In Cael. 13.22).

36 See Inwood, B., ‘Antiochus’ physics’, in Sedley, D. (ed.), The Philosophy of Antiochus (Cambridge, 2012), 188219CrossRefGoogle Scholar, at 205–7; cf. Dillon (n. 7), 91. We know that Antiochus held the mind to be divine (Fin. 5.11, 38, 43, 57; cf. Tusc. 5.38–9), but no report indicates a preference for quinta essentia over fire. For indirect evidence for Antiochus’ view, we might point to Varro, a follower of Antiochus, who cites the Stoic Zeno approvingly that the soul is derived from the immortal heat of the sun (Ling. 5.59) and held that the soul is heated air diffused through the body (Lactant. Op. Dei 17.5), or to Cratippus, a defector from Antiochus’ Old Academy to the Peripatos, who held the human soul to be imported externally from the world soul (Diu. 1.70–1).

37 Other intriguing parallels are ps.-Pl. Axiochus 370c5 (probably first century b.c.e.) and Diog. Laert. 3.67, both of which indicate that the Platonic soul is πνεῦμα.

38 Cf. Rep. 6.16: post-mortem souls will ascend to the heavens (the Milky Way); 6.17: all things are carried down towards earth except souls, which are immortal; 6.25: heaven is hanc sedem et aeternam domum of the soul. See also Sen. 77: the immortal soul is caelestis and has been sown in a mortal body; cf. Leg. 1.24. In his Consolatio (Tusc. 1.65–6 = fr. 21 Vitelli) Cicero adopted the Aristotelian doctrine of the soul as quinta essentia.

39 ὅταν δέ γε αὐτὴ καθ᾽ αὑτὴν σκοπῇ, ἐκεῖσε οἴχεται εἰς τὸ καθαρόν τε καὶ ἀεὶ ὂν καὶ ἀθάνατον καὶ ὡσαύτως ἔχον, καὶ ὡς συγγενὴς οὖσα αὐτοῦ ἀεὶ μετ᾽ ἐκείνου τε γίγνεται, ὅτανπερ αὐτὴ καθ᾽ αὑτὴν γένηται καὶ ἐξῇ αὐτῇ, καὶ πέπαυταί τε τοῦ πλάνου καὶ περὶ ἐκεῖνα ἀεὶ κατὰ ταὐτὰ ὡσαύτως ἔχει, ἅτε τοιούτων ἐφαπτομένη· καὶ τοῦτο αὐτῆς τὸ πάθημα φρόνησις κέκληται;

40 ἀλλ᾽ οὕτω λογίσαιτ᾽ ἂν ψυχὴ ἀνδρὸς φιλοσόφου, καὶ οὐκ ἂν οἰηθείη τὴν μὲν φιλοσοφίαν χρῆναι αὐτὴν λύειν, λυούσης δὲ ἐκείνης, αὐτὴν παραδιδόναι ταῖς ἡδοναῖς καὶ λύπαις ἑαυτὴν πάλιν αὖ ἐγκαταδεῖν καὶ ἀνήνυτον ἔργον πράττειν Πηνελόπης τινὰ ἐναντίως ἱστὸν μεταχειριζομένης, ἀλλὰ γαλήνην τούτων παρασκευάζουσα, ἑπομένη τῷ λογισμῷ καὶ ἀεὶ ἐν τούτῳ οὖσα, τὸ ἀληθὲς καὶ τὸ θεῖον καὶ τὸ ἀδόξαστον [b] θεωμένη καὶ ὑπ᾽ ἐκείνου τρεφομένη, ζῆν τε οἴεται οὕτω δεῖν ἕως ἂν ζῇ, καὶ ἐπειδὰν τελευτήσῃ, εἰς τὸ συγγενὲς καὶ εἰς τὸ τοιοῦτον ἀφικομένη ἀπηλλάχθαι τῶν ἀνθρωπίνων κακῶν. ἐκ δὴ τῆς τοιαύτης τροφῆς οὐδὲν δεινὸν μὴ φοβηθῇ, ὦ Σιμμία τε καὶ Κέβης, ὅπως μὴ διασπασθεῖσα ἐν τῇ ἀπαλλαγῇ τοῦ σώματος ὑπὸ τῶν ἀνέμων διαφυσηθεῖσα καὶ διαπτομένη οἴχηται καὶ οὐδὲν ἔτι οὐδαμοῦ ᾖ.

41 Cf. Pl. Ti. 42b3–5, 90a5–7; Phlb. 30a5–7.

42 Cf. Pl. Phd. 81a4–10; Phdr. 247e5.

43 Cf. Pl. Phdr. 246e2, 247d2, 248b6; Ti. 90c7–8.

44 Note especially 81c8–10: ‘My friend, we must believe that [the bodily] is weighty, heavy, earthly (γεῶδες) and visible, and when a soul possesses the bodily it is weighed down (βαρύνεται) and dragged back to the visible region …’

45 Cf. Pl. Phdr. 247a–248b.

46 Marcus’ claim that the soul is the seat of perception and that the senses act merely as windows to the soul recalls Tht. 184–6, but Corssen (n. 5), 17 aptly compares Phd. 65c.

47 Parallels include: the soul's ascent to upper regions because of its physical constitution (Sext. Emp. Math. 9.71); the region inhabited by souls (see H. Diels, ‘Zu Cicero Tusc. I 19,43’, RhM 34 [1879], 487–91); nutrition of stars and souls (Math. 9.73); and the rejection of Epicurean bugbears about the afterlife (Math. 9.70–1, 74; Tusc. 1.48). On the possible attribution to Posidonius, based in part on similarities with fr. 149 EK, see Kidd, I.G., Posidonius. Volume II: The Commentary (Cambridge, 1988), 550Google Scholar. On Sextus’ argument, see A.E. Ju, ‘Stoic and Posidonian thought on the immortality of the soul’, CQ 59 (2009), 112–24, at 113–14; Algra, K., ‘Stoics on souls and demons: reconstructing Stoic demonology’, in Frede, D. and Reis, B. (edd.), Body and Soul in Ancient Philosophy (Berlin, 2009), 359–87CrossRefGoogle Scholar, at 369–72. These parallels are not decisive to claim a common source for Sextus and Cicero, and the differences between Math. 9.71–4 and the Physical Argument are significant. Sextus emphasizes that these persisting souls are demons (εἰ οὖν διαμένουσιν αἱ ψυχαί, δαίμοσιν αἱ αὐταὶ γίνονται, Math. 9.74), but Marcus shows no interest in demonology. Similarly absent in Cicero is Sextus’ central counterargument against the Epicureans—namely, that souls are the cohesive causes of bodies (Math. 9.72). On the other hand, Sextus is silent on the post-mortem activity of souls so central to the Physical Argument (Tusc. 1.44–7). But the key difference is the conclusion of each argument. The Physical Argument concludes that souls are immortal. Sextus’ argument is rather a theological argument from preconceptions to prove the gods’ existence. The conclusion states that souls which have separated from the body and exist in the lunar region are identical to demons; if demons exist, a fortiori gods exist (εἰ δὲ δαίμονές εἰσι, ῥητέον καὶ θεοὺς ὑπάρχειν, Math. 9.74). Although the text claims explicitly that there is nothing in the region below the moon that could dissolve souls (τὸ διαλῦσόν τε αὐτὰς ἐν ἐκείνοις τοῖς τόποις οὐκ ἔχουσιν, Math. 9.73), it does not make the further jump to psychic immortality. Souls or demons might still be destroyed at the conflagration, as certain Stoics claimed (see below); cf. Algra (this note), 371–2. Or souls might lose tension gradually over time and dissolve of their own accord. Either way, Sextus’ argument does not necessitate the conclusion that souls or demons are immortal or eternal; indeed, Sextus conspicuously notes only that souls will remain ‘for a long time’ (πλείονα πρὸς διαμονὴν λαμβάνουσι χρόνον, Math. 9.73); cf. Jones (n. 7), 210. I thank this journal's referee for pressing these points.

48 On which, see Sedley, D., ‘The School, from Zeno to Arius Didymus’, in Inwood, B. (ed.), The Cambridge Companion to the Stoics (Cambridge, 2003), 733CrossRefGoogle Scholar, at 20–4.

49 Dougan (n. 7), 24. On the Stoic view generally, see Hoven., R. Stoïcisme et Stoïciens face au problème de l'au-delà (Paris, 1971)Google Scholar; Long (n. 7), 77–84. The Stoics accept the Platonic definition (cf. Phd. 64c) of death as separation of the soul from the body (e.g. SVF 1.137, 2.790).

50 See Epiph. Adu. Haeres. 3.508 and August. C. acad. 3.17.38 (both at SVF 1.146).

51 See Hoven (n. 49), 47–51; Celkyte, A., ‘The soul and personal identity in early Stoicism: two theories?’, Apeiron 53 (2020), 463–86CrossRefGoogle Scholar.

52 Ar. Did. fr. 39 (= Euseb. Praep. evang. 15.20.6 = SVF 2.809); Aët. Placita 4.7.3 (= SVF 2.810); SVF 2.817.

53 Tusc. 1.79–80 (= fr. 119 Alesse); see below. On Panaetius’ theory, see Hoven (n. 49), 51–7; T. Tieleman, ‘Panaetius’ place in the history of Stoicism, with special reference to his moral psychology’, in A.-M. Ioppolo and D. Sedley (edd.), Pyrrhonists, Patricians, Platonizers. Hellenistic Philosophy in the Period 155–86 b.c. (Naples, 2007), 103–42, at 112–13. For Panaetius’ rejection of the conflagration, see frr. 130–4 Alesse.

54 Ju (n. 47), 114–20. Especially relevant is Diog. Laert. 7.156, which distinguishes perishable individual souls from the imperishable world soul; cf. Plut. Comm. not. 1075A–B (attributed to Cleanthes and Chrysippus). The distinction between ‘immortal’ and ‘imperishable’ probably goes back to Chrysippus; see Ju (n. 47), 118–20; Long (n. 7), 77–80. If so, Posidonius would simply be reasserting Stoic orthodoxy, perhaps with a greater emphasis on the relationship between psychic immortality and demonology, for which see Algra (n. 47), 372–7.

55 Cf. Celkyte (n. 51), 468 n. 20. Marcus’ Platonic theory makes a different distinction between the souls of the wise and virtuous and those of the ignorant and vicious. They differ not in their permanence (since all souls are immortal) but rather in the speed and ease of their ascent to the heavens: the wise are unencumbered and swifter, the ignorant are laden with corporeal hang-ups and so slower (1.44–5, 75; cf. Amic. 13).

56 Cicero would thus be following the doxographical trend of sidelining Cleanthes’ position. For suggestions on the mechanism by which non-wise souls disintegrate prior to the conflagration, see Celkyte (n. 51), 477–80.

57 Cf. Ju (n. 47), 120, who notes that it is likely Cicero was aware of Posidonius’ distinction since Cicero tells us that Posidonius spoke of immortal souls (Diu. 1.64).

58 I am tempted to see this further anti-Stoic manoeuvre. Ju (n. 47), 117–18 suggests that Posidonius may himself be responding to the kinds of anti-Stoic objections raised by Cicero at Tusc. 1.77–80.

59 credamus igitur Panaetio a Platone suo dissentienti? quem enim omnibus locis diuinum, quem sapientissimum, quem sanctissimum, quem Homerum philosophorum appellat, huius hanc unam sententiam de inmortalitate animorum non probat. … alteram autem adfert rationem, nihil esse quod doleat, quin id aegrum esse quoque possit; quod autem in morbum cadat, id etiam interiturum; dolere autem animos, ergo etiam interire. [80] haec refelli possunt: sunt enim ignorantis, cum de aeternitate animorum dicatur, de mente dici, quae omni turbido motu semper uacet, non de partibus iis, in quibus aegritudines irae libidinesque uersentur, quas is, contra quem haec dicuntur, semotas a mente et disclusas putat.

60 On Panaetius’ arguments, see Woolf (n. 7), 211.

61 Ti. 69c–d, 90b–c; Resp. 611b–612c. Cicero does not signal any conflict between Platonic tripartition and the claim that the soul is simplex (1.71), nor any concern with the vexing question of how the Phaedo fits with the theory of the tripartite soul. Perhaps he thinks that the exposition in the Phaedo is limited to the rational soul (i.e. mens).

62 Cicero mentions Platonic tripartition elsewhere (Luc. 124; Diu. 1.60–1, a translation of Resp. 9.571c3–572b1). The doxography at Tusc. 1.20 relies on Ti. 69c–72d in associating soul parts with specific seats in the body. Elsewhere in the Tusc. (4.10), Cicero attributes to Plato and Pythagoras the bipartition of soul into rational and irrational. Aët. Placita 4.4 (DG 389–90) records that, on the most basic account, Pythagoras and Plato made the soul bipartite, but on the more particular account it is tripartite.

63 The first argument, which alleges that the resemblance between offspring and parents is proof for the generatedness and thereby perishability of souls, was already used by Cleanthes (SVF 1.518; cf. SVF 2.806 for Chrysippus); see Tieleman (n. 53), 112. The second argument states that, since the soul is susceptible to pain, it is thereby susceptible to destruction. A similar argument is found at Sext. Emp. Math. 7.70 (πᾶν τὸ ἀλγοῦν θνητόν ἐστιν), in an apparently Epicurean context, and was deployed by Carneades against the concept of immortality (Nat. D. 3.32, 34, 36). A similar idea may lie behind the Stoic argument for the destructibility of the cosmos at Diog. Laert. 7.141.

64 He was also an Aristotle-lover (ἦν γὰρ ἰσχυρῶς φιλοπλάτων καὶ φιλοαριστοτέλης), and allegedly departed from some Stoic doctrines in favour of the Academy and the Peripatos (καὶ παρενέδωκε τῶν Zηνων[είω]ν [τι διὰ τὴ]ν Ἀκαδημίαν [και τὸν Περί]πατον). He even produced an edition of Plato's works known to Galen; see J.B. Gourinat, ‘Le Platon de Panétius. À propos d'un témoignage inédit de Galien’, PhilosAnt 8 (2008), 139–51; cf. fr. 155 Alesse. On Panaetius and Plato, see Sedley (n. 48), 20–4. Tieleman (n. 53) makes the case that Panaetius was a rather orthodox Stoic with respect to moral psychology, against an older tradition which sees Panaetius as a radical reformer of Stoicism in light of his Platonic and Aristotelian leanings.

65 In saying that Panaetius only dissents from Plato on this one issue (hanc unam sententiam de inmortalitate animorum ) Marcus overstates his case for rhetorical effect: cf. Tieleman (n. 53), 113.

66 So says Asclepius (In Met. 991b3, page 90 Hayduck = fr. 146 Alesse): ‘Since [Panaetius] claimed that the soul is mortal, he wished to drag Plato down along with him.’ Α. Carlini, Studi sulla tradizione antica e medievale del Fedone (Rome, 1972), 32 calls Panaetius’ polemic a ‘rifiuto dottrinale’. See also M. Joyal, ‘“Genuine” and “bastard” dialogues in the Platonic corpus: an inquiry into the origins and meaning of a concept’, in J. Martínez (ed.), Fakes and Forgers of Classical Literature (Leiden, 2014), 73–93, at 83–5, who compares Diog. Laert. 2.64 (fr. 145 Alesse), where Panaetius distinguishes which first-generation Socratics composed true or genuine (ἀληθεῖς) dialogues—that is, true to Panaetius’ own standard of genuine Socratic philosophy. Some scholars have doubted the veracity of the reports on Panaetius’ bastardization of the Phaedo, alleging confusion by later commentators with the fact that Panaetius doubted the truth of the Socratic dialogues composed by Phaedo of Elis (διστάζει δὲ περὶ τῶν Φαίδωνος …, Diog. Laert. 2.64); see M. Van Straaten, Panétius. Sa vie, ses écrits et sa doctrine avec une edition des fragments (Amsterdam, 1946), 214. But this doubt seems unwarranted, stemming from an overly narrow understanding of the idea of ‘bastardizing’ a text; again see Joyal (this note). Given the centrality of the Phaedo to Tusc. Book 1, Cicero's choice to target Panaetius for refutation seems to provide indirect support.

67 Cf. a report by Epiphanius (Adu. Haeres. 3.508 = SVF 1.146) that Zeno held that the soul is ‘long-lasting pneuma’ (ἐκάλει τὴν ψυχὴν πολυχρόνιον πνεῦμα).

68 Argued by Sedley (n. 16), 10–11.

69 We find this strategy largely in Middle Platonist epistemology and moral psychology. For epistemology, see G. Boys-Stones, ‘Alcinous, Didaskalikos 4: in defence of dogmatism’, in M. Bonazzi and V. Celluprica (edd.), L'eredità platonica: studi sul platonismo da Arcesilao a Proclo (Naples, 2005), 201–34; Bonazzi, M., ‘The Platonist appropriation of Stoic epistemology’, in Engberg-Pedersen, T. (ed.), From Stoicism to Platonism (Cambridge, 2017), 120–41CrossRefGoogle Scholar. For ethics, see M. Bonazzi, ‘Eudorus’ psychology and Stoic ethics’, in M. Bonazzi and C. Helmig (edd.), Platonic Stoicism – Stoic Platonism (Leuven, 2007), 109–31; G. Boys-Stones, ‘Unity and the Good: Platonists against οἰκείωσις’, in B. Collette-Dučić and S. Delcomminette (edd.), Unité et origine des vertus dans la philosophie ancienne (Brussels, 2014), 297–320. M. Bonazzi has argued that the notion of ‘subordination’ is central to Antiochus’ approach to Stoicism; see his ‘Antiochus and Platonism’, in D. Sedley (ed.), The Philosophy of Antiochus (Cambridge, 2012), 307–33.

70 Imperial Platonists reject Stoic materialism in general (e.g. Plut. Comm. not. 1085E–1086B = BS 3V) and the Stoic notion of a corporeal soul in particular (Plut. Comm. not. 1084B; Longinus, fr. 20 = Euseb. Praep. evang. 15.21.1–3 = 9C BS; Numenius, fr. 4b des Places = 9D BS); see texts and discussion in Boys-Stones, G., Platonist Philosophy 80 b.c. to 250 a.d. An Introduction and Collection of Sources in Translation (Cambridge, 2018), especially 83–102Google Scholar.

71 If, as I have argued, the argument of Tusc. Book 1 is anti-Stoic, this seems to rule out Posidonius (cf. n. 58 above). The strategy of reproaching the Stoics for their doctrinal dissent from Plato, and the overall attempt to modernize Plato for a Hellenistic audience, certainly does remind one of Antiochus’ own philosophical strategy and aims. But while we may cite Antiochus as an influence on Cicero's thinking about the soul, I hesitate to identify Antiochus as a source. One further consideration against this is that Tusc. Book 1 and Antiochus crucially disagree about the relationship between the soul and the self: where Antiochus held that human nature consists of soul and body (Fin. 5.34, 44), Marcus explicitly denies this in favour of the more authentically Platonic line that the self is identical to the soul alone and not the body (Tusc. 1.52, a clear allusion to Pl. Alc. 1.129a–132c).