This article outlines when, how and in what kind of contexts the phenomenon of mental illness was recognized in the ancient philosophical texts, how mental illness was understood in terms of the body–mind interaction, and how mental disorders of the medical kind were distinguished from non-medical psychic disturbances. It establishes that, while the philosophers mostly understood mental illness along the lines of ancient medical thinking, their ideas, for example on the nature and location of the soul, informed their theories of mental illness.
In ancient medicine, known to us primarily through the ample corpus of Greek and Latin medical writing that extends from the earliest Hippocratic treatises to the Byzantine medical compilations, there is no established term for ‘mental illness’. Sure enough, several diseases and kinds of illness recognized and described in ancient medicine involved prominent symptoms affecting, for example mood, judgement or memory, and we find references to the mind or the soul being affected in them.1 Yet mania and melancholy, for example, were routinely discussed in the medical texts among conditions such as headache or paralysis; the modern reader is probably surprised to see how seldom it occurred to anybody to suggest that disorders with predominantly mental symptoms should be considered a distinct medical category, let alone that there should be specialist doctors to treat them. From the ancient point of view, all medical disorders were disorders of the body, treatable by the same principles.
In ancient medicine, there were no psychiatrists, that is doctors (iatros) of the soul (psychē), but in ancient philosophy there were. From Democritus and Socrates onwards, numerous philosophers professed to be ‘doctors of the soul’, taking care of the ills of the soul analogously to the medical doctors taking care of the ills of the body.2 These ills were essentially emotional dispositions and responses conceived of as being detrimental to human happiness, and they were often referred to as ‘diseases of the soul’. The philosophical therapy approaches varied, but they tended to be of the ‘cognitive’ kind. The idea of philosophy as therapy becomes especially prominent in Hellenistic philosophy. Of the three major Hellenistic schools, the Stoics aspired to instil into the soul an idea of ‘life according to nature’, helping it to overcome its self-centred emotional hang-ups and inciting it to look for purpose in the cosmos and identify with the cosmic reason (logos) governing all things; the Epicurean therapy sought to free people from ungrounded fears and anxieties concerning death and the supernatural world and to teach them to find contentment in the simple satisfaction of their basic needs; and the Pyrrhonian sceptics urged their adherents to discard unnecessary beliefs and theories and find peace of mind in the realization that uncertainty is the only (relatively) certain thing.3 Philosophical therapies of this kind were intended for people troubled by worries, fears and dissatisfaction; they were not intended for people with medical disorders affecting the mind.
Thus, ancient doctors were experts of bodily health and disease, while ancient philosophers were experts of psychic health and disease. But in this article, I push the philosophers out of their comfort zone and ask how they understood mental illness, that is, disorders of the mind belonging not to their particular expertise but to that of their medical counterparts. As noted, no neat category of ‘mental illness’ existed in ancient medicine. Moreover, ancient Greek and Latin vocabularies of mental unwellness are notoriously rich and ambiguous (Ahonen, 2014: 30–4; Padel, 1995: 13–33, 120–30; Thumiger, 2013), and words denoting ‘madness’ or ‘derangement’ (e.g., Greek mania or Latin insania and furor) could be used for outrageous and excessive behaviours and mental states as well as for actual medical disorders. Thus, the very first questions that need to be asked are did the ancient philosophers recognize the phenomenon of mental illness, and how can we reliably identify references to mental illness in the corpus of Greek and Latin philosophical texts? My approach has been to look for philosophical discussions of mental disturbances described as ‘illnesses’ or ‘diseases’ in the proper sense of the word, possibly with explicit reference to their medical and/or non-moral nature. Moreover, I have looked for connections and parallels between the medical and philosophical texts. For example, Hippocrates’ famous On the Sacred Disease, in which madness (mainesthai, ‘to be mad’) is ascribed to a wet condition of the brain involving excess movement, probably predates Plato and other philosophers discussed in this article,4 and it is possible to see echoes of its link between madness and movement in Plato and possibly also in Aristotle, even though we cannot be sure whether either of them was acquainted with the treatise. This article is a summary of my more extensive and systematic study (Ahonen, 2014), in which a full discussion of the material can be found. My study was motivated by two aims: first to close an evident gap in existing research, and second to demonstrate how the ancient philosophical musings on mental wellness and unwellness have, for their part, moulded the Western ideas of ‘mental illness’. This article shares these aims.
In the first part of this article I ask how the phenomenon of mental illness was recognized in ancient philosophy, and when and how the subject was approached. In the second part, I look in more detail into how mental disturbances were described and explained as physical and bodily events. Prior to concluding, I discuss briefly the very specific question of psychic invulnerability and mental illness.
Recognition of Mental Illness in Ancient Philosophy
When looking for the origins of a philosophical discussion, Plato is often a good place to start, and it is here, too. In the dialogue Laws, a distinction is made between two types of madness (mainesthai): madness due to illnesses (nosos) and madness due to other causes, such as an aggressive and troublesome character (934d). While the distinction appears to be made in passing, it is an important one. The Laws proposes, tentatively, a system of legislation with the express purpose of eradicating ‘diseases of the soul’ in the ideal city. This does not mean mental disorders as we understand them, but moral faults and shortcomings. The whole proposed social structure of the city serves to promote the psychic health of its citizens, making them reasonable, self-controlled and emotionally stable right from the birth. Still, because of the inevitable frailty of human nature, there must also be a penal code, to stipulate how to make good damages caused by criminal acts and, more importantly, how to guide the offenders towards ‘soul’s salvation’ (cf. 909a) by inflicting various corrective punishments.5 But those who are ‘mad’ because of illnesses are excluded from the community of the salvable souls. They are to be kept inside, firmly under the control of their family members (934c–d). Unlike other citizens, they are not held responsible for the offences they may commit (cf. 864d), and it is their family members who pay a fine if they fail in their duty to guard them. Thus, while the city actively seeks to ‘save the soul’ and correct the character of all kinds of evil-doers, nonconformist thinkers (especially atheists) included,6 it leaves the mentally ill alone, as it leaves alone also the hopelessly senile.7 The Laws is a notable text for recognizing clearly the phenomenon of mental illness in a social context: it recognizes that there are people with whom the normal ways of exerting social control do not work, and it suggests that these people must, effectively, be excluded from public life. Yet they are not to be destroyed, for they are ill, not evil.
Of course, Plato did not invent the idea of mental illness. The principle that a person with diminished powers of judgement due to illness or senility cannot manage his possessions was recognized in Greek legislation before Plato.8 But it was Plato who first provided something akin to an argued discussion on what the legal position of the mentally ill should be. Restraining the mentally ill and confining them to the house was evidently a common practice in Classical Athens.9 But it was the philosopher Xenophon, Plato’s contemporary, whom we first find suggesting that restraining a mentally ill person can be beneficial to the madman, and that a clear distinction must be made between people who are actually mad and people who are ignorant and foolish yet amenable to education and reasoning.10 Centuries later, we can see the trickle-down effect of these philosophical musings in Roman imperial law, where legislation concerning the mentally ill was notably sophisticated and humane (Toohey, 2013).
However, the clarity of the Laws is untypical of Plato. Most of his remarks around madness and mental and psychic unwellness are notably ambiguous. In the Timaeus, a distinction is made between diseases of the body and diseases of the soul. The human soul is tripartite, composed of reason (logos), spirit (thymos) and appetite (epithymia), spirit being the principle of aggression and honour-pursuit, while the appetite craves the pleasures of food, drink and sex. The parts are located, respectively, in the head, the heart and the liver. Epilepsy is described as a disease of the body, even though it affects the soul (85a–b); more precisely, it affects the head, the seat of the rational soul, when a mixture of white phlegm and black bile prevents the rational soul from exerting its proper movements. But similar causes can also give rise to conditions Plato designates as ‘diseases of the soul’, for he describes how various corrupt and misplaced humours and vapours can affect all three parts of the soul, causing ‘bad temper and dispiritedness, … rashness and cowardice, and forgetfulness and stupidity’ (87a). Moreover, Plato speaks of mania that is a ‘disease of the soul’, evidently meaning something quite different from the disabling mental illness of the Laws, for his example is a man troubled by excessive sexual desire, caused by excess seed (sperma) formed in his marrow that makes him ‘mad’ (emmanēs) and keeps him pursuing unhealthy pleasures (86b–d). Apparently, the conditions classified as ‘diseases of the soul’ in the Timaeus have a negative impact on the moral life of the subject, while epilepsy, perhaps, is not conceived of as having such an impact. Yet the distinction between bodily and psychic disturbances is vague; and this seems to be exactly the idea Plato wishes to convey, for he claims that nobody is wicked because of his own choice but because of the ‘evil condition’ of the body and because of the bad education received (86e) (Gill, 2000). Again, in the Republic Plato suggests that some extreme cases of mental illness could arise from bad character and bad education, and that badness could grow into full-fledged madness when there is nothing to thwart it, either in the person’s own soul (for in psychically healthy persons reason and, to an extent, spirit can control and subdue the beastly cravings of the appetite) or in the surrounding society (society being essentially the image of its citizens’ souls); a person at the mercy of his lowest impulses is a beast, willing to murder, to have incestuous sex, to taste human flesh (571a–576c).11
It may be baffling that Plato, so clear and decisive in the Laws, is so ambiguous elsewhere. The Laws is generally believed to be Plato’s last work. Does this disparity reflect a development in Plato’s thinking? Was the distinction between madness of mental illness and ‘madness’ of other kinds perhaps becoming more generally recognized and accepted during his lifetime? That is certainly possible. Yet I think the disparities have more to do with differences of approach than with issues of chronology. In the Timaeus, Plato wishes to establish that we all are, to an extent, mentally ill, living in imperfect, corrupt and corruptible bodies that exert a negative impact on our souls, preventing us from fulfilling our divine mission of living a life of reason.12 The Laws, on the other hand, is written not for an individual seeking his or her own salvation, but for the legislator looking for the best possible outcome in society. The legislator of the Laws is allowed wide powers for exerting social control, the means available to him ranging from imposing death penalties to brain-washing dissenters. Yet his realm is that of psychic health, not of physical health. He cannot help those who have lost their rational faculties due to old age or illness, and provisions must be made in the law for dealing with these situations in an orderly manner.
For Aristotle, the mentally ill are an exception, an aberration from the norms of human nature. There is virtually no discussion of mental illness per se in Aristotle’s writing. He recognizes that there are individuals who are deranged and mad, either temporarily or permanently, and that these people think and feel and behave strangely; but he suggests that we do not need to pay too much attention to them, for they do not, as it were, count in Aristotle’s account of humanity, which looks for the commonly accepted and commonly acceptable. In the Eudemian Ethics, Aristotle notes that the ‘sick and deranged’ can, much like small children, hold bizarre ideas, but no sensible person would take them seriously or start arguing with them, for they are known to be unamenable to reasoning.13 The Nicomachean Ethics contains some discussion of aberrant human behaviour.14 While human behaviour and mental characteristics normally vary within certain limits, some people are simply ‘beyond’. Aristotle describes this as ‘animality’ (thēriotēs).15 For example, some barbaric nations live by sense perception only, making no use of their rational faculties, and such subnormal individuals can also occur among otherwise normal people, like the notorious Sicilian tyrant Phalaris (sixth century BC) who rejoiced in torture and rape. Similar subhuman conditions can be caused by illnesses (nosos), such as mania or epilepsy, that give rise to irrational behaviour and strange fears, or even to bizarre incidents of violence and murder.16 Why mania would make the affected person murderous is not explained. Evidently, these illnesses either cause random aberrances, or else make their victims regress towards something base and bestial, like the horrendous desires of the appetite in Plato’s Republic that take over when the higher faculties are disengaged.
Evidently, this kind of animality is rare among the Greeks, and little provision is made for its occurrence in Aristotle’s ethical and political thought. But one might mention here his notorious idea of a ‘natural slave’.17 In the Politics, Aristotle claims that some people are fundamentally and irrevocably defective in their rationality, and while the function or purpose (ergon) of a fully developed human male is to use his rationality, the function of a natural slave is to use his body; and it is in the common interest of the master and the slave that the former makes decisions with his superior intelligence and the latter carries them out for him.18 Masters and slaves are typically marked out from the moment of birth,19 and the natural slaves of the Politics evidently correspond to the subhuman barbarians of the Nicomachean Ethics, their defective rationality being ultimately due to the unfavourable climatic conditions of their native regions.20 However, there are no references to Greeks with impaired rationality in the Politics, and it is evident that no Greeks should serve as slaves, no matter how their intelligence may fare during their life cycle. As to the care and control of the mentally ill in society, there are no overt suggestions in Aristotle.
Aristotle comments also on psychophysiological temperaments that make people behave in unusual ways without actual illness being involved. ‘Manic’ (manikos) people are characterized by emotional spontaneity and irascibility; moreover, they may have artistic talent due to their ability to have strong feelings.21 Melancholic people, again, are described as exceptionally sensitive and emotional.22 Evidently, their peculiar physical condition predisposes them to rash and vehement movements of the soul. Thus, they are bombarded by mental images and vivid dreams, and they profess to have, or perhaps actually have, prophetic abilities.23 They are impulsive and inconstant, following their quickly changing impressions, and they succumb to physical pleasures indiscriminately in order to relieve the constant ‘gnawing’ sensation in their bodies.24 They are in a permanent state of agitation and overdrive, sleeping little, eating much and yet remaining slender.25 A more systematic account of the melancholic temperament is offered in the spurious Problems 30.1. This famous discussion, often attributed to Aristotle’s pupil Theophrastus,26 suggests that the melancholic are emotionally unstable because of the precarious nature of the black bile itself and that they are also predisposed to actual madness. According to the discussion, black bile tends to become either very hot or very cold, and it affects both the body and the character (ēthos) of those who are by nature atrabilious. Thus, melancholics sometimes suffer from depression and ‘cold’ disorders such as paralysis, but sometimes they are exuberantly active, euphoric and manic. Moreover, if the black bile stays at a moderately warm temperature, melancholics may show exceptional talent, for then they are mentally agile, alert and sensitive, which makes them for example great poets or statesmen.
When Aristotle speaks of madness, he always means the real thing, namely mental illness. But the ancient Stoics made much of a distinction between two kinds of madness, and for a special reason, as the Stoic school taught that ‘Everybody is mad (mainesthai)’.27 The idea of madness as the common lot of all mankind goes back to the Stoic view of virtue and vice. According to the Stoics, virtue is the condition of the perfected human soul, while vice is the condition of the rest of us, there being nothing in between virtue and vice.28 Most likely, virtuous human souls do not exist – perhaps they never did, and never will. Yet the Stoics liked to dwell on the details of how their ‘sage’ (sophos) would do things and experience life. The claim that everybody excepting the sage is ‘mad’ was intended to demonstrate the immense gap between our miserable lives and the almost unimaginable constancy of the sage: we hardly know what we are doing, given the confusion of changeable impressions and vague ideas in our souls that pull us in all directions,29 while the sage alone acts in a reasoned manner, consistently progressing on his god-given path.
The Stoics insisted that the madness of all mankind is true madness. Yet they emphasized that it is not the same as the madness of mental illness. The ancient references to the Stoic distinction between the two kinds of madness are notable for their clarity and definitiveness. Yet they all occur in rather late authors, and we do not know when and by whom the distinction was first made. Like Plato in the Laws, Cicero and Seneca, representing the point of view of the Stoics, emphasize that the legal position of the mentally ill is different from the position of those said to be ‘mad’ in the special Stoic sense. However, they do not make recommendations but refer to actual practices. Cicero notes that the ancient Laws of the Twelve Tables prohibit a madman (furiosus) from managing his property. This is necessary, for such madness entails ‘mental blindness in every relation’ (mentis ad omnia caecitas), whereas those said to be ‘mad’ in the Stoic sense can lead a normal life and perform their civic duties.30 Seneca notes that the Stoics trust the people they call ‘mad’ with suffrage and jurisdiction, while the other kind of madness, the one treatable by medication, excludes the sufferers from such responsibilities.31 In one of his moral letters, he imagines an exchange with the third-century Stoic Aristo of Chios.32 Seneca depicts Aristo as insisting that while the ‘madness of people in general’ (insania publica) and the madness treated by medical doctors (quae medicis traditur) differ as to their causes and treatments, they are essentially similar, and that madmen of both kinds are unable to appreciate advice and benefit from it; and from this Aristo infers that insania publica can be cured only by an all-encompassing philosophical revelation in which the madness is shattered in one blow, similarly to the medical madness being shattered by the violent treatment of purgative drugs.33 Seneca disagrees with this, claiming that madmen of both kinds can benefit from advice and counselling. The Stoic distinction is also referenced by the fifth-century medical author Caelius Aurelianus, who suggests that the medical madness of the Stoics is the same condition that he himself discusses under the rubric furor sive insania.34
The claim that ‘Everybody is mad’ was a notorious piece of Stoic doctrine, often put to perverse use by the opponents of the school. Thus, the Stoics felt the need to point out explicitly that they, too, made the same distinction as everybody else between ‘madness’ and ‘badness’, and that they did not suggest that we should all consider medical treatment to attain psychic health and wellbeing.35 There may have been a further practical point to the distinction, namely the wish to rule out the possibility that the public would perceive the Stoic teachers as professing actual ability to cure mental illness. However, this concern is not voiced in the extant sources, nor do we hear of the Stoics turning away help-seekers for being too ill for philosophical therapy. On the contrary, Seneca suggests that the mentally ill, too, can benefit from philosophical advice, even if it is not able to cure their condition.36
The Sceptics and the Epicureans
There is relatively little discussion of mental illness in what remains of the ancient Epicurean and sceptical writings. Madness and mental derangement are occasionally mentioned, and the problem of convincing hallucinations, especially, is explored in epistemological contexts. In the second century AD, the philosopher and physician Sextus described the 10 ‘modes’ (tropos) inducing the Pyrrhonian suspension of judgement (epochē).37 This suspension is in turn conducive to peace of mind (ataraxia). The modes argue that we cannot grasp the objects of our inquiry as they are in themselves, because our perceptions are always informed, for example, by the specific and individual qualities of our perceptive organs and by the circumstances in which the inquiry takes place. According to the fourth mode, diseases such as phrenitis make some individuals perceive things differently from the majority.38 Sextus speaks of ‘humours’ (chumos) that inform the impressions, but his point is not to explain how the distorted perceptions happen, but to argue that, however they happen, there are no people whose perceptions are not affected by their bodily condition – impressions informed by mental illness are just another variation. Indeed, it is possible that the so-called ‘sick’ have a better and truer grasp of reality than the so-called ‘healthy’; but we cannot tell one way or the other.39
The Epicureans had less interest than the Stoics in making a stark distinction between mental illness and ‘madness’ of the unphilosophical mind. For Lucretius, the first-century BC Epicurean poet, the occurrence of mental disturbances of both kinds points to the same conclusion: the human soul (anima) and mind (animus or mens, conceived of as the rational part of anima) are passible and mortal. Lucretius cites the occurrence of grief, anxiety, fear, delirium, lethargy, drunkenness, epilepsy and madness as evidence for the soul’s and mind’s passibility, not always bothering to make clear which of these are bodily conditions that ‘confuse’ the soul and which are conditions of the soul itself.40 What matters is that they all point to the same conclusion: there is nothing impassible in the human soul, nothing that is safe from decay and disease. For Lucretius, this passibility indicates two things: first, it lends support to the Epicurean worldview in which everything, the human soul included, is made of atoms that are bound to disperse at some point, and second, it gives assurance that there is no afterlife, no ‘us’ after death.
As mentioned in the introduction, there was no established term for ‘mental illness’ as a concept or category in ancient medicine. Of the extant medical writers, Celsus, Aretaeus and Caelius Aurelianus, for example, discuss mania, melancholy and phrenitis among bodily illnesses; from a modern point of view, this choice saved them from the difficulty of trying to define which medical conditions should and should not be regarded as ‘mental’ in nature.41 But there is a notable, albeit little known, attempt at classifying mental symptoms and disorders and establishing a distinct medical category for them in the writings of Galen, the second-century AD medical giant. Galen was not only an extremely influential doctor and medical writer, but also a notable philosopher, discussing issues of ethics, psychology, epistemology, philosophy of language and logic. His commitment to the Platonic tripartite model of the soul and the ethical ideal of nourishing the powers of reason and subduing the passions of the lower parts of the soul permeates many of his medical treatises.42 While Galen did not coin a term for mental illness, he worked on the classification issue by using concepts derived from the philosophical musings on the mind and the soul. He speaks of hēgemonikai energeiai, ‘functions of the ruling-faculty (hēgemonikon) of the soul’, that is, the rational functions, such as memory and thought, which he contrasts with the ‘physical’ (physikai) and ‘psychic’ (psychikai) functions, the former denoting the vegetative functions of the body and the latter the functions of perception and voluntary movement. All these functions belong naturally to the human being, and the inability to exert any of them amounts to a medical condition. The term hēgemonikon was first coined by the Stoic philosophers, to denote the central, coordinating faculty of the soul which the Stoics located in the heart.43 Galen adopted the term, but located his hēgemonikon firmly in the brain, claiming that it operates through the nervous system and a substance called psychic pneuma, contained in the ventricles of the brain and in the nerves.44
In the work Causes of Symptoms (Symp.Caus.), Galen classifies medical symptoms according to the functions they affect. He distinguishes three types of symptoms that affect the rational functions: (A) total loss or destruction (apōleia) of an ability or function; (B) damage (blabē) to an ability or function; and (C) distortion (ektropē) of an ability or function.45 Class A includes, for example, cases of a complete loss of memory or of abilities such as reading and writing, while B includes more moderate symptoms of the same kind. But it is class C that is the most interesting. Symptoms of this class are characterized as ‘derangement’ and ‘erroneous movements’, for, in contrast to classes A and B, the rational functions are not just impeded but actively distorted. As the rational functions take place in the brain, all symptoms affecting these functions are associated with physical conditions of the brain. More precisely, ‘mania’ denotes a hot derangement without fever, while ‘melancholy’ denotes a cold derangement without fever, and ‘phrenitis’ is the condition in which there is a hot derangement with fever and inflammation. Thus, the three ancient disorders that the modern reader is most likely to perceive as instances of ‘mental illness’ are here brought together under a single rubric – despite the fact that phrenitis was an acute condition while mania and melancholy were chronic conditions, and despite the fact that phrenitis was associated not only with the brain but also with the diaphragm, while melancholy was associated with the upper digestive tract. Galen uses the philosophical notion of hēgemonikon as a tool to classify medical disorders and manages to explicate the essential common feature of the ‘madness’ disorders, namely, that they are conditions in which the rational functions are engaged but working in a disorderly and distorted manner. As far as I know, this theoretical elegance is not found in any other ancient medical writer.46
The Physical Nature of Mental Illness, and How to Cure It
So far, I have described how mental illness was recognized by major ancient philosophical writers. In this section, I explore how the philosophers understood the physical nature of mental illness, and what kind of cures were suggested and referenced.
For Plato, the human soul is tripartite, each part having its own assigned abode in the body. As described in the Timaeus, the bodily environment moulds and informs all three parts, and even the rational part, albeit immortal, is affected by physical illnesses as it is confined to the head. Thus, mental illness appears to be a disorder of the head, in which corrupt and misplaced humours and vapours interfere with the movements of the rational soul. But Plato emphasizes that anoia (‘mindlessness’, i.e. the condition in which nous, the rational soul or the intellect, cannot function properly) can be brought about by all kinds of bodily disturbances, and even the natural growth of the body in children impedes rational thought – which is why children become fully rational only after their growth ceases (44a–b). Moreover, the Timaeus suggests that all diseases, those of the body as well as those of the soul, should be treated similarly. Health must be pursued by engaging actively in both mental and physical exercise, for active, harmonious movements protect the organism from the violent and disorderly movements that are apt to take place in a passive body (88c–e). Medications should always be avoided and used only as the last resort, for their violent effects push the system into further disturbance, giving rise to new illnesses (89b–d). The rational soul benefits from philosophical contemplation of the universe and its inherent harmonies, for this exercise physically rectifies the circles that the rational soul consists of, as it is made in imitation of the world soul and the circles of the celestial bodies (90c–d). Thus, the Timaeus appears to suggest that there is no need for specific cures for mental illness, unless in particularly severe cases medication must be used to purge the body of the harmful substances. The Laws and the Republic contain no discussion of the treatment or curability of mental illness.
Unlike Plato, Aristotle ascribes the physical location of cognition and perception to the heart. He argues that the soul must be in the middle of the body to impart movement,47 and claims that the heart is the first organ to develop in an embryo, endowing it with vital blood and heat.48 Accordingly, Aristotle suggests that disorders with mental symptoms occur in the cardiac area. He insists that epilepsy takes place there.49 In the Parts of Animals, he describes how the intellect (dianoia) and perception can be disturbed by a ‘hot, residual fluid’ arising from below towards the cardiac area.50 No name is given to this disturbance, but the reference is evidently to a kind of mental illness; possibly, Aristotle is thinking of phrenitis.51 In the same work, he notes that the brain can also play a part in mental disturbances, for the brain is the coldest organ of the body, counterbalancing the hotness of the heart, and when the brain fails in its tempering function, ‘diseases, madness (paranoia),52 and death’ ensue.53 In the Problems, a spurious work probably produced within the Peripatetic school, we read that people suffering from mania have excess heat in the cardiac area and this disturbs the soul, making it move uncontrollably, so that adequate thought and perception become impossible.54 Drunken people and growing children are in a similar condition. Thus, in the Aristotelian/Peripatetic account, mental illness arises around the heart when the soul, whatever its exact physical nature, is disturbed by abnormal bodily conditions – hot conditions leading to derangement, drunk-like behaviour and perceptual distortions, while cold conditions lead to stupor and loss of function.
Aristotle notes that medication (pharmakeia) is used to cure the ‘deranged’ of their bizarre beliefs.55 In the Aristotelian Physiognomics, a Peripatetic treatise (or rather, two treatises edited as one) probably written in the third century BC, we read of doctors treating mania and freeing the soul of its symptoms by purging the body with drugs and dietary measures; the success of this cure demonstrates the close interdependence of the body and the soul on which the physiognomist’s art is based.56 Thus, the philosopher makes no claims of expertise as far as the treatment of mental illness is concerned, but relies on the medical doctors’ expertise, using their practices as cues for gaining insight into the special relation of the body and the soul/mind. This was, evidently, the approach most ancient philosophers adopted, and Plato with his anti-medication advice was a rare exception.
The Stoics and the Epicureans also located cognition and reason in the cardiac area. Evidently, mental illness must take place there too. The Greek Stoics used the word melancholia to denote mental illness, thereby suggesting black bile as a typical cause of such disturbances, and the Stoic Posidonius describes melancholy as a ‘bodily affection (pathos) that concerns the soul’.57 In this, melancholy is categorically different from the psychic affections proper, such as anger or fear, for even though melancholy manifests itself in the workings of the soul, it is essentially a disturbed state of the body. Yet the distinction between ‘mental’ and ‘psychic’ disturbances is not one between physical and non-physical, for the soul is, in the Stoic account, a robustly physical thing, consisting of pneuma, a special mixture of heat and air. It is rather that while anger and fear, for example, originate in the soul as the soul, melancholy originates elsewhere in the body, or perhaps in the soul as a physical body. Hence, they are treated differently. While emotional upheavals are treated by adjusting one’s beliefs and philosophical outlook, melancholy is treated by medication, and its treatment is trusted to medical professionals.58
Epicurus taught that the human soul, like everything else in the cosmos, is made of atoms, and that its special sensitive and perceptive nature is due to its composite atoms being exquisitely small, smooth and mobile.59 As noted earlier, the poet Lucretius goes to great lengths to demonstrate the passibility and mortality of the soul, for he wishes to assert that there is a definite limit to all human suffering in death. At the same time, Lucretius’s insistence that the soul is its composite atoms and nothing else beyond blurs the line between mental illness and non-medical disturbances of the soul, for all these indications of the soul’s vulnerability are, ultimately, irregularities in the composition and configuration of its atoms. Yet he evidently believes that this line must exist, for these disturbances are to be treated differently. Fears, worries and anxieties must be alleviated by philosophical therapy, which guides us to realize their groundlessness as the Epicurean worldview is absorbed and applied.60 But the mind that is disturbed in the medical sense must be healed by medicine, and Lucretius describes, rather fascinatingly, how medical treatment can add new atoms to the soul, remove noxious ones, or cause the atoms’ configuration to change.61 In his account, it is not the abode or instrument of the soul that is treated by medicine – it is the soul itself.
In ancient medicine, the cardiocentric model existed side by side with the encephalocentric model, until the latter began to gain ground steadily from the Hellenistic time onwards, as the advances made in Alexandrian medicine concerning the anatomy and physiology of the brain and the nervous system became more widely known and accepted.62 In the second century AD, Galen found it difficult to understand how anyone could fail to be convinced by the overwhelming evidence for the encephalocentric model. For him, the brain was the origin of the nervous system, as dissection (as well as vivisection and experiments conducted on live animals) so evidently showed.63 The fact that both Hippocrates and Plato – his medical and philosophical hero – ascribed cognition to the brain (or so he interpreted their writing) demonstrated that humans had long known the true function of the brain, even though some ignorant philosophers had distorted this knowledge by their perverted reasonings. Accordingly, Galen believed the brain to be involved in all medical mental disorders, and, being a medical doctor as well as a philosopher, he put forward original theories as to their causes and treatments. Here, I can make only some brief comments.64 Melancholy, in Galen’s view, is caused by black bile that affects the brain either directly or indirectly, being present in the whole of the body, in the brain only, or around the diaphragm, emitting harmful vapours upwards.65 The end result is always the same: the black substance renders the brain into an ‘inner darkness’, causing fear (phobos) and depression (dysthymia).66 The patients find it difficult to explain their downcast and anxious moods, or to offer inappropriate and bizarre explanations. Delusions can also occur. One melancholy patient believed he was a cockerel, flapping his arms.67 Phrenitis is caused by hot yellow bile disturbing the brain, and Galen divides it into three types, for it may affect perception, rational judgement, or both.68 Moreover, the yellow bile may be present in the brain itself, or affect the brain from the diaphragm. Galen tells of a man who threw his precious possessions out of a window during an episode of phrenitis, concluding that, as the man could correctly identify and name each object he was about to throw, there was nothing wrong with his perceptive faculty and only his judgement was faulty.69 On the other hand, Galen himself, in his youth, suffered from an attack of phrenitis, which made him hallucinate tiny bits and pieces protruding from his mattress and garments and try to grasp at them in vain (a symptom still known by the ancient name carphologia, ‘straw-picking’), but he claims that his rational faculty remained intact throughout the illness.70 Mania is the third major mental illness recognized by Galen. It is caused by hot bile and resembles phrenitis;71 but otherwise Galen has little to say about it.
For Galen, the treatment of mental illness is straightforward, for it consists in correcting the prevailing physical imbalance and, when necessary, evacuating the pathogenic humours by bloodletting or purgatives.72 Unlike some of his medical colleagues, Galen never proposes ‘psychotherapeutic’ measures to address directly the mood or beliefs of the mentally ill.73 Thus, there seems to be a clear divide between mental illness and psychological problems such as unwanted and immoderate emotions (discussed in Galen’s philosophical works), for he suggests that the latter must be treated by challenging one’s accustomed behaviour and thought patterns and gradually adopting new and better ones.74 But interestingly, Galen’s approach varies. Following Plato, he claims that psychological problems (anger and greed in particular) occur when the irrational parts of the soul are not properly controlled by the rational part, and that they must be treated by correcting this psychic imbalance. But as the parts are firmly located in the body (reason in the brain, spirit in the heart and appetite in the liver), he occasionally suggests that we could, in fact, address our psychic problems and shortcomings by moderating our daily diet rather than by engaging in philosophical introspection.75 Throughout his work, we see Galen candidly acknowledging that he does not and indeed cannot know the substance of the soul (Hankinson, 2006); and the way in which he is intrigued by the possibilities of both medicine and philosophy for improving ourselves is unique in antiquity.
But Would It Affect US?
For ancient philosophers, mental illnesses were physical disorders of the head, the heart or the brain. Typically, they required medical treatment (medication), and in this they were different from the ‘diseases of the soul’, for these were treatable by philosophical therapy in which the individual’s gradual development towards greater enlightenment and self-control played a pivotal role. Yet the line was sometimes blurred, as we have seen happening in Plato’s Timaeus and in Galen.
That said, mental illness was not necessarily something that affected people at random. Aristotle expresses an opinion commonly held when he suggests that physical illnesses are often outside our control and therefore not reprehensible, but that ill health due to neglect is reprehensible.76 According to medical authors, excesses of behaviour and emotion (e.g. heavy drinking, sexual excess or a fit of anger) could lead to mental illness.77 Philosophers emphasized the need to take care not only of the soul but also of the body. In Plato’s Timaeus, we are instructed to attune ourselves to the higher harmonies of the universe as protection against illnesses of all kinds,78 and the Stoics even suggested that their (hypothetical) sage would be his ‘own best doctor’, being uniquely acquainted with his body and its needs.79 So perhaps a philosophical lifestyle, consisting in moderation and emotional control, could protect against mental illness; but surely not even that could guarantee health.
Yet some Stoics apparently believed that the sage would not succumb to mental illness, come what may. Diogenes Laertius notes that there were differing opinions on this: ‘Chrysippus says that virtue can be lost, while Cleanthes says that it cannot. Chrysippus says that it can be lost as a consequence of drunkenness or melancholy, whereas Cleanthes says that firm apprehensions prevent its being lost.’80 What is at stake here is the invulnerability of the sage’s soul. Chrysippus, the founding father of mainstream Stoicism, asserted that the sage’s soul was by no means invulnerable. If it was affected by drunkenness, a bout of melancholy or a dose of powerful drugs, it lost its hard-gained virtue, that is, its state of epistemic and moral perfection, and was rendered into a kind of subhuman condition that was neither virtue nor vice.81 But Cleanthes, an older contemporary of Chrysippus and more austere ethical thinker, believed that virtue would also entail extraordinary physical stability of the soul, to protect against external influences of for example black bile; for after all, the Stoics also believed that a virtuous person’s soul could outlive the body, remaining in the world as spirit until the next conflagration destroyed everything and a new cosmic cycle began (Algra, 2011). Becoming a sage was perhaps not a true option for the adherents of the Stoic school, but at least they could be inspired by the idea that it might be possible for the soul to rise above the normal human condition, that is, the susceptibility to the haphazard processes of illness and decay.
Some Platonists also believed in the invulnerability of the soul, or at least of its rational faculty. Galen comments on this position and the difficulties it raises in his Capacities of the Soul: ‘[C]ertain self-styled Platonists … hold that the soul, though impeded by the body in sickness, performs its specific activities when the latter is healthy, and is neither assisted nor harmed by it.’82 These Platonists claim that the human soul, and especially its rational part, is mostly independent of the body. Yet they concede that diseases – and we must think here of mental illnesses – can impede the soul from performing its functions. Thus, these Platonists would say that if we are affected, for example, by melancholy, we are temporarily unable to perceive and think correctly, yet our soul is essentially unaffected – it is just inactive, or perhaps even absent,83 until the illness subsides and the bodily environment is again stable enough to allow it to resume its functions. This does not apply just to the exceptionally virtuous, for all human intellects are of the same other-worldly nature. Later, the Neoplatonist Plotinus (third century) even claimed that the intellect was not incarnated at all into the human body, suggesting that in mental illness the higher functions continued, only without our being empirically aware of them.84 But for Galen, of course, this kind of position is untenable, for, as we have seen, he emphasizes that in mental illness the rational functions are distorted, not just inactive. Moreover, he argues that all three parts of the soul are heavily informed by their bodily environment, in sickness as well as in health. To him, the occurrence of phenomena such as mental illness or drunkenness reveals the true nature of the human soul: it is always a ‘slave’ to the body’s humoral balances and imbalances.85
I have explored how the phenomenon of mental illness was recognized and how such disorders were explained in ancient philosophy. Identifying the relevant passages and discussions in the vast corpus of ancient Greek and Latin philosophical writing is not an easy task, given especially the terminological problems I have referred to, but it can be done. In particular, texts that reference or problematize the distinction between mental illness and psychic problems of a non-medical and/or moral kind, such as unwanted emotional dispositions, are of key importance.
The ancient philosophers understood mental illness along the lines of ancient medical writers. However, it is not always clear which way the influences go, for there are gaps in the evidence: in particular, the medical thinking of the Hellenistic period is poorly documented as compared with later antiquity. Evidently, concepts such as melancholy developed within both disciplines. The philosophers regarded mental illnesses as physical disturbances occurring in their supposed abode of the soul or its rational part (the head, the brain or the heart): these disturbances interfered with the functions of the soul, resulting in aberrations of thought and perception. Humoural imbalances and especially black bile were referenced as possible and likely causes; but more precise theorizing was usually left to medical experts.
The contexts in which mental illness was discussed varied. Philosophical psychology, the body–soul interaction and the physical nature of the soul were typical topics and contexts for the subject of mental illness to arise, for the occurrence of mental illness seemed to indicate the soul’s dependence on the body and its health. The question of hallucinations and delusions also cropped up in epistemological contexts. Some authors show more interest in actual medicine than others, and I have also discussed the medical authority Galen, who makes use of philosophical concepts in his medical thought and ponders on the respective roles of medicine and philosophy for psychic health.
Evidently, ancient philosophers believed that mental illness was curable by medication and that doctors could treat it effectively. Medication often meant hellebore, a toxic purgative causing vomiting and diarrhoea.86 To us, the ancient trust in this treatment may seem puzzling; certainly nobody would suggest that ancient medications can be considered effective by modern criteria, but we have few means of assessing how favourably or unfavourably the ancient methods and modes of treatment affected the patients.
Given the division of labour between ancient doctors and philosophers, the distinction between mental illness and non-medical psychic problems appears to be a significant one. Yet there is little discussion in the philosophical texts on how to tell the two apart in practice. While medical authors occasionally note the challenges of this task,87 the philosophical writers seem to regard the difference as self-evident: madmen were supposed to behave and express themselves in ways so extravagant that there could be no doubt about the nature of their condition. Furthermore, ‘diseases of the soul’ were conceived of as being rather stereotypical expressions of the common human desires and fears, while mental illnesses often had bizarre and fantastic, or else downright bestial, elements. Yet as I have described, there are instances when the distinction becomes blurred, or even disappears, for example in Plato’s Timaeus, in the Aristotelian account of the melancholic temperament, and in Galen.
- Of diseases recognized in ancient medicine, mania, melancholy and phrenitis, in particular, involved notable mental symptoms. But mental symptoms also occurred in lethargy, satyriasis, hydrophobia, nightmare, hysteria and epilepsy, for example, and even lovesickness could be regarded as a medical disorder; see Oribasius, Synopsis ad Eustathium 8.8, and Paul of Aegina 3.17. On mental illness in ancient medicine generally, see Thumiger, 2017, and the articles in Thumiger and Singer, 2018.
- For Socrates, cf. the opening scene of Plato’s Charmides; for Democritus, see fragment 31 (Diels and Kranz, 1952). More generally, see Nussbaum, 1994.
- On ancient philosophical therapies, see e.g. Knuuttila, 2004; Nussbam, 1994; Sorabji, 2000.
- On the Sacred Disease 14.2–5. The text is believed to date from the latter half of the fifth century BC; see Jouanna, 2003: lxx–lxxiv.
- On the penal system in the Laws, see Saunders, 1991.
- Cf. 908a–909d on the institution of sōphronistērion, ‘house of correction’.
- 929d–e: Mentally ill or senile father loses his position in the household and is assigned a status akin to that of a child.
- The dikē/graphē paranoias (the proceeding by which a mad or senile person could be officially ordained to lose the right to manage his affairs) was recognized in fifth-century BC Athens. In the Roman Law of the Twelve Tables (fifth century BC, modelled after Greek legislation), a madman’s (furiosus) affairs were to be managed by a guardian or the relatives (Table V).
- Cf. Aristophanes’ Wasps, where the slaves guard the ‘mad’ Philocleon inside the house on the orders of his son. The son tries to cure his father first by persuasive words, then by religious rituals, and finally by making him sleep in Asclepius’s temple (verses 115–124); locking the old man in the house is the last resort.
- Memorabilia 1.2.49–50; Xenophon claims to be citing the teachings of Socrates.
- However, Plato is not here describing the phenomenon of mental illness as such, but rather describing what kind of men might be produced by the worst imaginable kind of society and political system.
- Cf. Timaeus 42a–d.
- Eudemian Ethics 1.3, 1214b29–33.
- Nicomachean Ethics 8.5, 1148b15–1149a20.
- Greek thēr denotes a beast or even a monster, while zōon is the neutral term for animal.
- Aristotle mentions a man who was afraid of a ferret because of ‘illness’, and references two cases of homicide and cannibalism due to mania.
- On Aristotle and slavery, see: Brunt, 1993; Heath, 2008; Karbowski, 2013.
- Politics 1.2, 1252a31–34.
- Politics 1.5, 1254a21–24.
- Politics 7.7, 1327b18–31.
- Categories 8, 9b35–10a1; Rhetoric 1.9, 1367a33–1367b3; and Poetics 17, 1455a22–1455b23.
- For full discussion, see Van der Eijk, 1990.
- On Divination in Sleep 2, 463b15–23 and Eudemian Ethics 7.14, 1248a39–40.
- Nicomachean Ethics 7.10, 1154b11–15.
- On Sleep 3, 457a25–33.
- Theophrastus was interested in mental illness and abnormal states of consciousness and wrote a (lost) treatise entitled On Melancholy (see Diogenes Laertius 5.44); the Problems discussion may be a summary of this.
- This claim is referenced by numerous ancient authors, comprising philosophers, poets, satirists and medical authors. It may have been of Cynic origin, and Chrysippus appears to be the first Stoic to make use of it (see Chrysippus’s ethical fragments 658 and 662–670 in Stoicorum veterum fragmenta). For a full discussion, see Ahonen, 2018.
- For an overview of the Stoic ethical system, see Schofield, 2003.
- Cf. Stobaeus 2.7.5b13.
- Cicero, Tusculan Disputations 3.11.
- Seneca, De beneficiis 2.35.2.
- It is not known whether the exchange is made up on the basis of the rudiments of Aristo’s ethical teachings or whether Aristo actually discussed madness and mental illness in his (now lost) writings. On Aristo’s ethics, see Porter, 1996.
- Letter 94.17.
- Tardae passiones 1.144.
- There is a curious anecdote in Aulus Gellius (Attic Nights 17.15) about the academic philosopher Carneades who took hellebore to purge his body of corrupt humours when about to write against the doctrines of Zeno the Stoic. This is the only reference I know when such treatment is used to enhance intelligence and not to cure a disease.
- Cf. Caelius Aurelianus, Tardae passiones 1.166–167.
- Outlines of Pyrrhonism 1.36–186. For interpretation, see Annas and Barnes, 1985.
- Outlines of Pyrrhonism 1.101–103.
- Pyrrhonism inspired the medical school of Empiricism which Sextus also represented; see: Hankinson, 1995: 225–36; Nutton, 2004: 147–9. However, we do not know whether the Empiricist doctors treated their mentally ill patients differently from other schools.
- Lucretius, De rerum natura 3.459–525, 824–825.
- Cf. note 1.
- On Galen’s psychological theory, see: Donini, 2008; Hankinson, 1991.
- The Stoics compared the human soul to an octopus, the more peripheral powers sprouting from the central faculty like tentacles.
- For Galen’s anatomical understanding of the brain, see Rocca, 2008: 247–56. Psychic pneuma is described in Galen as the ‘instrument’ of the soul, for the physical parts and the physiological substances through which the powers of the soul are exerted are never identified with the soul.
- Symp.Caus VII.200–204. All references to Galen are by Kühn volume and page numbers; English translation in Johnston, 2006: 203–301. For a slightly different version, see Differences of Symptoms (Symp.Diff.) VII.60–62; English translation in Johnston, 2006: 180–202.
- However, the classification of symptoms/disorders according to the functions they affect features only in some of Galen’s writings. For example, the great pathological work On Affected Places (Loc.Aff.) discusses medical conditions according to the bodily part that is affected, and while this approach lumps together mania and melancholy as disorders of the head and the brain (Book III), phrenitis, with its diaphragmatic association, is discussed elsewhere (Book V), and hallucinations, again, are discussed among ocular disorders in Book IV.
- Movement of Animals 8–10, 701b33–703b2.
- On Youth and Old Age 3–4, 468b16–469b20.
- On Sleep 3, 457a7–14: epileptic fit is like sleep.
- Parts of Animals 3.10, 672b26–30.
- The Greek word phrēn (pl. phrenes) means both the midriff (sometimes specifically the heart) and the mind (cf. phronein, ‘to think’).
- The Greek paranoia means being ‘beside’ (para) oneself as far as the mind (nous) is concerned; it does not refer to paranoid ideation.
- Parts of Animals 2.7, 653b1–8.
- Problems 30.4, 957a1–6; cf. also Problems 27.4, 948a13–30, where mania is associated with disturbance and heat in the lungs.
- Eudemian Ethics 1.3, 1214b29–33.
- Physiognomics 4, 808b11–27.
- Posidonius, fragment 154 (Edelstein and Kidd, 1972).
- Cf. Seneca, De beneficiis 2.35.2 and Epistle 94.17, discussed above.
- Epicurus’s letter on the physics of matter is extant at Diogenes Laertius 10.35–83; the soul is discussed at 10.63–66.
- Epicurus’s Kyriai doxai or Principal Doctrines (Diogenes Laertius 10.139–154), comprising 40 concise sayings, crystallized the school’s ethical teaching and were learnt by heart by the followers.
- De rerum natura 3.510-522.
- On Herophilus’ import, see Von Staden, 1989.
- Galen never dissected human bodies, instead using pigs, monkeys and goats as his model animals; see Mattern, 2013: 147–55.
- For full discussion, see Ahonen, 2014: 145–61.
- Loc.Aff. VIII.176–193.
- E.g. Symp.Caus. VII.203.
- Loc.Aff. VIII.190.
- Loc.Aff. VIII.225. But Galen’s understanding of phrenitis varies. In Loc.Aff., ‘sensory’ phrenitis is regarded as a disorder of the perceptive organs and nerves, and is not, strictly speaking, a mental disorder, whereas in Symp.Diff. (VII.60–62) Galen attributes perceptual distortions to the rational faculty, as they are dysfunctions of phantasia, i.e. the imaginative faculty, rather than the sensory organs.
- Symp.Diff. VII.61.
- Loc.Aff. VIII.226–227; see Mattern, 2013: 64.
- Symp.Caus. VII.202 and Loc.Aff. VIII.166.
- E.g. Loc.Aff. VIII.185. Dietary measures are appropriate in milder cases (Loc.Aff. VIII.192) and can also be taken to prevent the recurrence of the illness.
- E.g. Rufus of Ephesus (late first century AD) used wine, sex and music to treat melancholy; Galen was familiar with his writings. See fragments 58–67 in Pormann, 2008. While these measures were supposed to lift the patient’s spirits, they also physically counteracted the cold and dry imbalance of melancholy.
- See Galen’s Passions of the Soul (Aff.Dig.), Character Traits (Mor.) and Avoiding Distress (Ind.), all in English translation in Singer, 2013. On Galenic therapy, see: Gill, 2010; Hankinson, 1993; Sorabji, 2000: 253–60.
- See especially the short treatise The Capacities of the Soul Depend on the Mixtures of the Body (QAM, also in Singer, 2013), in which both emotional control and intellectual enhancement are achieved by modifying lifestyle and diet.
- Nicomachean Ethics 3.5, 1114a21–31.
- E.g. Caelius Aurelianus, Tardae passiones 1.147 and 181; Aretaeus, De causis et signis diuturnorum morborum 1.6.2.
- Timaeus 88c–e.
- Stobaeus 2.7.11m.37–40.
- Diogenes Laertius 7.127.
- See Simplicius’ commentary in the Categories, Commentaria in Aristotelem Graeca VIII, 402, 22–26.
- QAM IV.805; translation Singer, 2013.
- Cf. Philo of Alexandria, De specialibus legibus 3.99.
- Enneads 1.4.9–10; see Blumenthal, 1997: 273–81.
- E.g. QAM IV.779.
- Ancient ‘hellebore’ could refer to one of two plants with similar properties, Helleborus niger and Veratrum album. While there was evidently a popular belief that hellebore ‘cured’ madness, for ancient medical authors it was only one component of the treatment.
- E.g. Galen, De praenotione XIV.630–635, and Aretaeus, De causis et signis acutorum morborum 1.5.8.
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Originally published by History of Psychiatry 30:1 (10.09.2018) under the terms of a Creative Commons Attribution-NonCommercial 4.0 International license.