Kazantzidis, George. 2023. “Notes on Phrenitis in Galen and Sextus Empiricus.” In “Γέρα: Studies in honor of Professor Menelaos Christopoulos,” ed. Athina Papachrysostomou, Andreas P. Antonopoulos, Alexandros-Fotios Mitsis, Fay Papadimitriou, and Panagiota Taktikou, special issue, Classics@ 25. https://nrs.harvard.edu/URN-3:HLNC.ESSAY:103900200.
Mental faculties and cognitive capacities can be damaged, compromised, twisted, and affected in all sorts of different and interesting ways.  The ones who undertake to discuss the wide range of attending dysfunctions are usually doctors; among them, Galen stands out as the most systematic and insightful physician in antiquity—not only when it comes to this particular subject, but generally.
My first text comes from De locis affectis (Περὶ τῶν πεπονθότων τόπων), Book 4. Galen states in this instance that:
Theory in Galen always comes hand in hand with examples drawn from clinical experience at the level of everyday life and medical practice, and so the author, in the text that follows, goes on to report on cases of phrenetic patients corresponding to each of the categories he has just outlined. The first concerns a patient who exhibits symptoms of type A of phrenitis—which is to say that the affected individual can see and hear perfectly fine, but he develops a strange, to say the least, way of thinking:
Back to Galen’s text. The whole incident is orchestrated as a spectacle of sorts (δι’ ἧς οἷόν τ’ ἦν ὁρᾶσθαί τε αὐτὸν καὶ ὁρᾷν τοὺς παριόντας … ἐθεάσαντο)—one that starts on a light-hearted tone that reminds us of comedy (τῶν δὲ μετὰ γέλωτος ἀξιούντων … οἱ δὲ γελῶντες ἐκεκράγεισαν  ), and then suddenly takes a tragic turn (γελῶντες μὲν ἐπαύσαντο, πεσόντα δὲ προσδραμόντες ἀνείλοντο συντριβέντα). The element of laughter in the story should not strike us as unusual: mentally incapacitated people were not always treated with kindness in antiquity, and there are several sources testifying to incidents of ridicule and inhumane abuse.  Such lack of empathy applied generally to deformity and disability—categories of the abnormal and the deviant, under which illness seems to be finding its place, time and again. Suffice it to be reminded here of the evidence provided by Plutarch at the point where he is telling us of the people in Rome who, instead of taking pleasure in paintings and works of art, haunt, instead, “the monster-market” (τὴν τῶν τεράτων ἀγοράν), driven by a morbid and twisted fascination with the sight of disabled people:
The inherent cruelty of an emotionally distanced crowd who are watching the ill and the deformed with a mix of curiosity and enthrallment is a common denominator between the texts of Galen and Plutarch. But there is also a crucial difference, and this has to do with the fact that, unlike Plutarch’s poor freaks who are exhibited as silent and passive objects, Galen’s madman is not at all disempowered. In fact, he is the one to engage the crowd in dialogue in the first place, insidiously luring them into his twisted game.
So much for type A of phrenitis. But what about type B, the one in which the patient, as we are told, thinks rationally, but he sees and hears strange things? Galen illustrates this type with the following story:
Two observations are pertinent at this point. Τhe first concerns the clinical details of the story. What Galen is describing here is a typical case of “carphology,” otherwise known as floccillation, defined in medical idiom as the action of grasping at imaginary objects or plucking at one’s bed clothes, and recognized as a characteristic of people affected by high fever and delirium.  The second observation relates to what modern psychiatry defines as “gradualism.” According to the gradualist approach, mental illness is not a matter of fixed and tidily delineated nosological categories which are easy to identify and to distinguish from a positive state of “health”; gradualism posits that illness should instead be approached in terms of degrees by which certain pathological states manifest themselves, without necessarily establishing a clear-cut break from the realm of reason.  This is to say that Galen’s medical case, in which he presents himself as conversing, rationally, with his friends is no less phrenetic than that of the patient who has lost it and throws stuff from the window. Crucially, Galen warns his friends that they should help him so that phrenitis does not take full hold of him (καὶ βοηθεῖτέ μοι, μὴ φρενιτίσω)—meaning that the illness is already there, although not to an advanced degree.
I am talking here of minimal optical illusion in the sense that the cognitive and perceptual mistake involved in floccillation is not a major one; it is a sensory mistake that sometimes can take place even under normal circumstances, when, for instance, one is tired or feels dizzy. But in other instances, paratuposis can lead to grave illusions. In the context of discussing Stoic epistemology, Sextus Empiricus mentions that the Stoics allow for a distinction between representations which they call “vacuous” and those which they label “distorted”: for the first case Sextus invokes the example of tragic Orestes who sees the Furies chasing him; for the second case, that of the ‘distorted’ representations, he is citing the case of Heracles who kills his own children under the impression that they are the children of Eurystheus:
The distinction outlined in this passage is, in modern terms, that between a hallucination and an illusion.  When (Aeschylus’) Orestes sees the Furies chasing him, there is no existing person or object near him that he is misperceiving as such; what he comes face to face with is a fully formed hallucination which is entirely a product of his own imagination. Heracles, on the other hand, sees his children (who are actually present), but driven by a fatal spell of madness, mistakes them for something else—someone else’s children. This is what Sextus describes as a paratuposis.
The Orestes whom Sextus has in mind in this passage is the one from Aeschylus’ Choephori. Consider the following lines (1048–1062):
[Orestes] ἆ ἆ·
σμοιαὶ γυναῖκες αἵδε Γοργόνων δίκην,
φαϊοχίτωνες καὶ πεπλεκτανημέναι
1050 πυκνοῖς δράκουσιν· οὐκέτ᾿ ἂν μείναιμ᾿ ἐγώ.
[Chorus] τίνες σε δόξαι, φίλτατ᾿ ἀνθρώπων πατρί,
στροβοῦσιν; ἴσχε, μὴ φοβοῦ, νικῶν πολύ.
[Or.] οὐκ εἰσὶ δόξαι τῶνδε πημάτων ἐμοί·
σαφῶς γὰρ αἵδε μητρὸς ἔγκοτοι κύνες.
[Ch.] ποταίνιον γὰρ αἷμά σοι χεροῖν ἔτι·
ἐκ τῶνδέ τοι ταραγμὸς εἰς φρένας πίτνει.
[Or.] ἄναξ Ἄπολλον, αἵδε πληθύουσι δή,
κἀξ ὀμμάτων στάζουσι νᾶμα δυσφιλές.
[Ch.] εἷς σοι καθαρμός· Λοξίας δὲ προσθιγὼν
1060 ἐλεύθερόν σε τῶνδε πημάτων κτίσει.
[Or.] ὑμεῖς μὲν οὐχ ὁρᾶτε τάσδ᾿, ἐγὼ δ᾿ ὁρῶ·
ἐλαύνομαι δὴ κοὐκέτ᾿ ἂν μείναιμ᾿ ἐγώ.
[Or.] Ah, ah!
I see these hideous women looking like Gorgons—
clad in dark-grey tunics and thickly wreathed with serpents! I can’t stay here!
[Ch.] Dearest of men to your father, what are these fancies that are whirling
you about? Hold firm, don’t be afraid—you have won a great victory!
[Or.] These afflictions are no fancies I am having;
these are plainly my mother’s wrathful hounds!
[Ch.] Ah, the blood is still fresh on your hands;
that, you see, is the cause of this confusion falling on your mind.
[Or.] Lord Apollo, there are more and more of them!
And they’re dripping a loathsome fluid from their eyes!
[Ch.] There is only one way you can be purified: Loxias,
by laying his hand on you, will set you free from these sufferings.
[Or.] You don’t see these creatures, I do!
I’m being driven, driven away! I can’t stay here! 
Orestes’ unmistakable symptom of madness in these lines takes the form of a visual hallucination. Where the Chorus sees only Orestes and the corpses of Aegisthus and Clytemnestra, Orestes sees the Chorus and the corpses, but also Erinyes. Glenn Most observes:
Glenn Most’s reading is supported by Sextus Empiricus’ distinction between Orestes’ hallucinations and Heracles’ illusions; according to Sextus, the crucial difference between the two is that in the first case the image of the Erinyes is entirely conjured up in the patient’s mind.
This is not the only time that Orestes makes his appearance in Sextus’ text. In Adversus Mathematicos Book 8, the paradigmatic example of the mad hero returns once again, only this time it is not the Aeschylean but the Euripidean Orestes. The difference is important; for while in Aeschylus Orestes is hallucinating the Furies, in Euripides he is mistaking Electra for one of them. This time it is not a hallucination but an illusion that the matricide is suffering from (Adversus Mathematicos 8.247.1–249.15):
For historians of philosophy, this is an incredibly important passage, as far as Stoic epistemology, the notion of phantasia and the distinction between cataleptic and non-cataleptic impressions are concerned.  For the purposes of the present chapter, it is worth drawing attention to Sextus’ employment of the term φρενιτίζοντες, which, in association with μελαγχολῶντες, are used as generic labels for everything that counts as “mental illness.”  One does not expect to find in Sextus the delicate distinctions made by Galen between mania, phrenitis and melancholia;  after all, this is a philosophical text and Sextus’ main concern lies with illustrating philosophical issues such as: what is true and false, existing and non-existing, plain and deceptive, and so on. To the extent that mental illness signals a violent break from—what is commonly and conventionally agreed, among sane people, to constitute—“reality,” it offers Sextus a prime opportunity to explore through it the very essence of what it means to be present or not, real or unreal;  but other than that, he is not interested in pursuing further details of a more clinical sort; a couple of prominent tragic examples of insanity  suffice to do the job for his argument.
Yet, despite the different priorities imposed by each category / genre of texts, philosophical and medical, phrenitis stands as a common denominator in the sense that both Galen and Sextus use it in order to draw a distinction between (i) a loss of touch with reality that remains, to some degree, anchored to the objects or persons which surround the patient and (ii) a loss of touch that is total, in which case the image that the patient is seeing are concocted entirely in his mind. What is more, just as Sextus borrows from medical terminology, so does Galen turn his eye on philosophical jargon. Here is what we read at De symptomatum differentiis 3.4 (7.60.3–7.61.19 K.):
The story of the physician Theophilus (for whom we know next to nothing, other than Galen’s report of his episode of delirium) is incredibly interesting in its own right and would deserve a discussion of its own. For now let us just note the fact that in the context of an extremely systematic discussion of mental affections, Galen seizes the opportunity to stress, once again, that when someone is “not quite right in his mind,” this can manifest in two ways: either the patient makes strange thoughts  or he sees and hears things that are not there (there is, of course, a third distinct possibility, arising from the combination of these two mental affections). This time, Galen speaks of παραφροσύνη by which we should understand something fairly similar to phrenitis. What is more, the misperception of distorted or empty images is given in a language (ἔν τε τῷ μὴ καλῶς φαντασιοῦσθαι) that directly involves the notion of phantasia, which, as we have seen above, is the terminus operandi through which Sextus Empiricus discusses the case of Orestes.