Medicine and Metaphor in Late Antiquity: How Some Recent Shifts are Changing the Field

In the title to the 2016 exhibition The Soul is an Octopus, curated at the Berliner Medizinhistorisches Museum der Charité, the centrality of metaphor to ancient ways of conceiving of the body and life is evident.¹ Metaphor is explicitly employed to make sense of invisible and abstract medical ideas, with specific reference to the mapping onto the body of the soul. The exhibition, which was based on texts considered foundational in the history of medicine from the classical to early Roman imperial period, constituted an “intervention” into the museum's main display, a collection of pathological specimens donated by Rudolph Virchow in 1899 that had been arranged with the intention of creating “a spatialised ‘map’ of the human body showing all diseases known at the time.”² “Interventions” of this kind, as the curators of the 2016 exhibit point out, “are especially interested in the differences, the ‘otherness’ of the permanent presentation's main narrative, and the absent perspectives or dimensions.”³ In this particular case, what they aimed to insert into the visual narrative was something dynamic and invisible that gives vitality to human life – the soul. To convey the abstract philosophical ideas that informed medical theories of the soul in the ancient to early-imperial texts, they invited an artist to visually translate the medical metaphors these texts employed. In this way they could bring into visual dialogue with the pathological specimens and their view of the body a much older way of conceiving of the body, soul, and life that nonetheless remains “fundamental to the ways we think and speak about health and disease, sanity and insanity today.”⁴ 

The Berlin exhibition was focused on how the soul is described metaphorically by philosophers and medical theorists from Hippocrates, Plato, and Aristotle to Galen. In the writers and thinkers of Late Antiquity medical metaphor likewise comes to the fore, this time in relation to a world that is now substantially Christianized. In this period metaphors derived from dietetics and surgery are increasingly applied to society, politics and religion. Until recently, many scholars encountering medical metaphors in non-medical texts have viewed this kind of appropriation as simple analogy.⁵ That is, while something is described as like something else, the likeness is purely descriptive. From this perspective the original domain from which the metaphor is derived (medicine) is distinct from the new domain where it is employed (Christianity and its discourse). This new domain uses the former to make sense of, and convey, certain ideas, but, in this view, anything essentially medical in the ideas conveyed does not transfer. When a medical metaphor is viewed in this way, the “amputation” of bishops from the body of the Church through exile, for instance, is not literal amputation – it is only notional (a colorful way of describing an act or process). It has no actual therapeutic intention or effect.

This view of medical metaphors as ornamental goes hand in hand with medical-historical approaches of this same period which have sought to extract records of actual medical theory or practice from the writings of various Church fathers.⁶ Seeking contemporary historical medical data, scholars mine in Christian texts like homilies medical analogies that are drawn between priests and physicians or between the body of the Church and the human body. The domain to which the medical metaphor is applied, however, they consider of little interest.⁷ In the medical historical view medicine is used simply to talk about something else, and so the two things are ontologically distinct. The medical data embedded in the text is all that is important. What is said to be analogous is irrelevant. In this respect, the drive to extract historical medical data from what are perceived as non-medical texts served to reinforce the view of metaphor as a simple literary device. This previously dominant view that medical metaphor is ornamental or figurative, in which an analogy is drawn between two things that remain discrete, is increasingly being challenged in recent scholarship,⁸ not least in the articles in this special issue of Studies in Late Antiquity.

The purpose of this article is to introduce a number of ways of engaging with medical metaphors in late ancient discourse. What the 2016 Berlin exhibition illustrates is that medical theorists and practitioners themselves required metaphors to conceptualize and convey ideas about processes of the body that were dynamic, invisible to observation and dissection, or abstract. Digestion, the activities of different kinds of pneuma, mental illness, and the composition, location, and interaction of the body with the soul all fit within this category.⁹ This is one use of medical metaphor: to make sense of medicine itself. As has long been recognized, however, in the ancient to late-ancient world medical metaphors abound in non-medical texts as well. Here they are employed in explicitly non-medical domains. How we make sense of such metaphors—medical metaphors employed by non-medical practitioners or theorists in non-medical contexts—is more open to question. This is the subject of the following articles and discussion. They show how, in the world of Late Antiquity, what appears on the surface to be simple analogy can be both deployed and understood in ways that are more complex. Domains like politics, religion and medicine that appear discrete can, on deeper investigation, be discovered to overlap and interconnect. This opens up questions about how the authors who used medical concepts and metaphors perceived their own role as practitioners and about how we categorize, and consequently read the purpose of, the texts in which such metaphors are employed. In particular, the articles in this special issue are concerned with the persistence in Late Antiquity of permeability and slippage between the literal and the metaphorical.

In order to demonstrate the complexity of the relationship between the literal and the metaphorical, I introduce and discuss three shifts that have been taking place in how we view medicine in Late Antiquity. These, I argue, open up a variety of ways of thinking about medical metaphors in Late Antiquity and how they are used in the religious discourse of Late Antiquity in particular. These shifts are treated in brief since the emphasis in this issue is on the individual case studies presented in the four articles that follow. Yet they serve to highlight the importance, when exploring the use of medical metaphor in Late Antiquity, of engaging with the continuities between Antiquity and Late Antiquity with respect to the thought-world and worlds of knowledge in which such metaphors functioned. The three shifts I adduce are informed by cultural studies, anthropology, cognitive linguistics, and moral psychology, and have generated an increased recognition of the permeability between medicine and philosophy, and thus between medicine-philosophy and religion. It should be noted that the approaches that inform these shifts are frequently intertwined. They are also suggestive. More could be said about medical metaphors from, for instance, the perspectives of the material turn in Late Antiquity, the rise of asceticism, and gender studies.

As I indicated in the introduction, although medical metaphors are prevalent in Christian texts, scholars have been slow to acknowledge the slippage between the literal and metaphorical precisely because these metaphors are deployed in a non-medical domain. The view of such metaphors primarily as analogy or colorful ornamentation has been persistent. This view is changing, however, in response to changes in how we understand Greek and Roman medicine. One such change that has been taking place over the past two decades is an understanding of illness and the treatment of illness as natural rather than foreign to religion and religious concepts.¹⁰ This change of perspective G. E. R. Lloyd largely attributes to the rise of medical anthropology, with its emphasis on how concepts and practices of health and illness are influenced and shaped by cultural norms and social institutions.¹¹ While this is an important factor, Amanda Porterfield also credits “advances in brain science and erosion of the Cartesian dichotomy between mind and body” with “a major shift in scientific and medical attitudes towards religion” in “the last two decades of the twentieth century.”¹² She situates the origins of this now recovered view in ancient Greek medicine where approaches to healing “often coexisted, and intermingled, with religion.”¹³ 

The appropriation of medical language by writers in Christian Late Antiquity is thus not novel, but should be viewed as culturally normative, a natural progression from much older ways of viewing society and illness in Classical Greek and Roman or Near Eastern culture. Lloyd intimated this more than 15 years ago, pointing out that the concept of disease in ancient to late ancient Greek thought extended beyond human beings to include groups of humans: the polis or a social entity.¹⁴ The idea that a polis is sick when not in harmony or riven by stasis or otherwise out of balance is predicated in turn on a conceptualization of the polis or social entity as a human body.¹⁵ This latter concept plays a powerful role in Christian discourse in Late Antiquity in multiple ways. It informs not just the labelling and treatment of social groups viewed as deviant, but also views about the health of the social body. The resultant metaphors can be quite explicit in their application of contemporaneous medical knowledge. As an example, in a forthcoming article Jessica Wright argues persuasively that, in combination with Galen's encephalocentric model of the body, application of the body politic metaphor to the Christian body, the Church, produced a highly productive concept for John Chrysostom—namely, that the bishop is the brain that regulates the health of Christ's body.¹⁶ In referring to the bishop as the Church's brain, there is significant slippage here between the literal and the metaphorical. Similarly, as Éric Fournier has recently shown, it was no coincidence that the use of amputation language to refer to the exile of bishops deemed heretical increased in the fourth and fifth centuries CE. Concern with preserving the health of the Christian body required that necrotic parts be excised. The exile of bishops, in this view, was literally therapeutic.¹⁷ The concept that the body politic or a social group can be sick or diseased, and thus require literal healing, is one that has a very long, influential, and problematic history.¹⁸ 

Medical anthropology encourages us to ask how this commonplace social-medical concept—society as a body subject to health and disease— informs Christian ideas in Late Antiquity in other ways. Antigone Samellas, for instance, demonstrates how, informed by the concept of the social group as a body, a neglected Hippocratic aphorism concerning pain contributed to ascetic notions of a community of co-sufferers.¹⁹ Here the body's capacity to suffer both physical and psychic pain is transferred onto the social body. The aphorism to which she draws attention states that, when two pains occur concurrently but in different locations, the more violent pain masks the other.²⁰ As her argument progresses, she demonstrates in detail and at length that this culturally-informed commonplace fostered within Christian circles not just endurance of pain, but also sensitivity towards the marginalized as co-sufferers. For Gregory of Nazianzus and John Chrysostom in particular, as she shows, the promotion of ascetic practice and of care for the marginalized are co-related and have origins in medicine. Their concepts of health, pain, and the social body were all intuitive and part of their cultural heritage.

The cultural constructions of health and illness that informed Late Antiquity extended beyond the physical body and its functions into the realm of the abstract. As Lloyd points out, equally natural in Greek thought from the very beginning was the concept that, if disease is construed (albeit not consistently) as evil, then “a powerful way of conceptualizing evil (however understood) is as a disease.”²¹ This moral, more abstract conceptualization of illness found a natural home in eastern Christian thought, where sin (deviation from virtue) rapidly became conceived of as a sickness.²² From these examples and through the lens of medical anthropology, with its requirement that we view the understanding of health-illness and the treatment of illness as culturally and socially informed, we can see that medicine—and therefore medical metaphor—is not distinct from, but rather natural to, religion.

The understanding of health-illness and the treatment of illness were expressed in their own way in the ancient Judean culture and religion from which Christianity emerged. Recognition of this is enhancing our appreciation of the richness of the cultural context from which the medical metaphors of Late Antiquity draw. For example, the recent work of Yitzhaq Feder on pollution beliefs in ancient Near-Eastern and Jewish thought demonstrates the intimate relationship between culturally conditioned ways of viewing contamination and culturally specific, ritualized actions and responses.²³ His interest emerges from a desire to understand the conceptual underpinnings and origins of Hebrew ritual law, particularly in regard to purity regulations. While contamination avoidance or disease avoidance is part of the evolution of human behavior, the pollution beliefs linked to that response are, as he points out, culturally variable.²⁴ Feder argues for a feedback loop between individual (intuitive) contamination appraisals and (reflective) collective pollution beliefs or theories that can result in the pollution beliefs or theories themselves becoming automatic and non-reflective within a particular culture or society. It is those pollution theories that

Pollution beliefs and beliefs about purity, both of which can result in purification behaviors, are two sides of the same coin.

In both Greco-Roman culture and the ancient Near-Eastern societies with which Jewish culture is aligned, bodily emissions and blood are significant triggers. Their legal, moral, and behavioral implications in Roman society Sarah Bond draws out in her study of taboo trades.²⁶ The implications for ritual behavior in Greek and Roman religion are brought out by the studies of Robert Parker and Jack Lennon.²⁷ Their valency and impact in Near-Eastern and Judean culture is in the process of being unpacked by Feder.²⁸ His explorations of the role of culture in cognition help to explain how the same trigger that could produce disgust and avoidance in most social contexts could in a highly specific social (religious) context take on a purifying, rather than polluting, role and elicit the opposite emotional response. That is, whereas in Greek and Roman culture blood was usually highly polluting and needed to be ritually cleansed, it could conversely, when brought together with normative medical concepts, become a purifying agent. The distinction between social and ritual context that Feder makes is important in this regard. In this respect, it was both intuitive and natural for late antique preachers to claim that, within the baptismal liturgy when Christ's blood is transformed into the eucharistic wine, it nourishes and gives (eternal) life to the embodied soul.²⁹ This is because in baptism Christ gave birth to us, and so, like any woman who has given birth, he nourishes us with his own blood (the blood that flowed from his side).³⁰ As soon as the blood the initiate is given to drink is conceived of as the blood of a mother that nourishes, it evokes not blood that pollutes, but breast milk. As John Penniman points out, in the medical theories that prevailed in Late Antiquity, breast milk constituted the mother's own blood transformed through bodily processes. In the context of Christ's and a mother's breast milk, blood is a positive substance that nourishes and is literally life-giving for the infant.³¹ On one level the metaphor of the eucharistic wine as breast milk is a conceptual transference that could be considered non-literal, but at another, we can now see that within the cultures from which Christianity emerged there is also a highly developed, intuitive set of pollution theories that encouraged the believer to accept the nourishing and life-giving properties of that transformed blood as real and literal. Those pollution theories, with their legal, moral, and ritual entailments, were as much a part of and shaped medical concepts and theories as ideas that a modern biomedical understanding of medicine would view as strictly medical.

A further layer of complexity is added when we contemplate the reception of Judean pollution theories and medical concepts, with their origins in Near-Eastern cultures, in Greco-Roman culture and vice versa. As a discipline, medical anthropology prompts us to take into account the likelihood that, however it was understood in the original cultural setting, a concept drawn from one tradition takes on other nuances when it is introduced into, or viewed through, the conceptual lens of another.³² Likewise, within a single society, even without external influences the progression of cultural and social change is likely to cause the understanding of a concept or the set of ideas associated with it to alter over time. Late Antiquity is a period in which, as a series of factors brought about substantial migration and social change, concepts of these kinds were constantly being blended and adapted. For the scholar engaged in teasing out what was conceptually automatic and natural and how this informed the choice of a medical metaphor, how a metaphor was employed, and how literally or figuratively it was expected to be understood is a delicate and complex process. What the studies discussed in this section highlight, nonetheless, is that undertaking that process is essential. What they bring to the fore is a recognition that the understanding of health-illness and its associated behaviors are culturally and socially informed. They demonstrate how these concepts and behaviors cross the boundaries between medicine and religion, blurring the distinction between literal and metaphoric. They also show that these same concepts and behaviors naturally have a strong moral dimension. These studies have something important to say not just about the choice of medical metaphors, but about their employment, too. Medical metaphors, they suggest, can play a role not just in reflecting, but also in constructing, social norms. These studies highlight three areas in which this can occur: in the organizing of community, the shaping of practices and rituals, and the orienting of individuals’ morality. How medical metaphors can effect this is to some extent unpacked in the next section.

The recognition of the pervasiveness of medical concepts across how a society thinks and of the link between medical metaphors, moral judgments, and cognition points towards a second shift that informs how we read medical metaphors. This shift concerns not the approach to medicine but the approach to metaphors themselves. At the same time, recognition that there is a moral dimension to medical metaphors invites us to explore this angle further, again through the lens of cognition. In this section I discuss in brief the relevance of Conceptual Metaphor Theory (CMT) for approaching medical metaphors. I then move to a discussion of the potential insights to be gained through applying Moral Foundations Theory (MFT). If medical anthropology has highlighted the role that culture, politics, and other social factors play in how health and illness are conceived and how health care is provided, cognitive linguistics challenges us to consider how the medical ideas and concepts that are pervasive in a society are used to think with.

In regard to the cognitive linguistic approach—metaphors as conceptual (something used to think with)—the work of George Lakoff and Mark Johnson is considered to constitute a watershed.³³ Before that point metaphor was viewed for the most part as a literary device, the purpose of which was ornamental.³⁴ Lakoff and Johnson made the case that, on the contrary,

Since then an entire field (cognitive linguistics) has grown up around this proposition, with a discipline area (Conceptual Metaphor Theory) devoted entirely to the study of metaphoric concepts and their employment within, and across, a diverse range of human languages, including sign language.³⁶ In this respect, cognitive linguistics encourages a distinctively different reading of the role of linguistic concepts from that of linguistic anthropology, the approach of medical anthropologists.³⁷ Linguistic anthropology is primarily interested in speakers as social actors and seeks to understand language as cultural practice. There are intersections between the cognitive and anthropological branches of linguistics, but linguistic anthropology does not focus on metaphor per se, and approaches its use from a different perspective.

In this section I am concerned with how metaphors are used by societies and individuals to make sense of the world around them—and therefore how medical concepts relate to experiences common across cultures—and less with how medical language is socially and culturally encoded. The basic argument of CMT is that our brain/mind is embodied, and thus we habitually make sense of abstract concepts by relating them to everyday embodied experiences, since the latter are what we are most familiar with.³⁸ In conceptual metaphors we understand “one conceptual domain in terms of another conceptual domain.” In CMT the abstract concept onto which a more concrete idea is mapped is the target domain. The source domain is the aspect of everyday experience used to make sense of it. The resultant conceptual metaphor is distinct from, while also the foundation of, “metaphorical linguistic expressions.”³⁹ What is of significance in this regard for the study of medical metaphor is that one of the most common source domains used to make sense of a more abstract domain is the Human Body.⁴⁰ A subspecies of that source domain is Health and Illness.⁴¹ Among the common target domains, on the other hand, are Morality, Society/Nation, and Religion.⁴² From the perspective of cognitive linguistics, we can see that at least two of the extended concepts of disease discussed in the previous section—that evil is a sickness, and that a polis or political entity could suffer illness (e.g. in the form of civil war)⁴³—are in fact simple conceptual metaphors. In the first (evil is a sickness), the target domain is Morality; in the second (that a polis can suffer illness), the target domain is Society/Nation. In both, the source domain is Health and Illness, a natural and common part of human embodied experience.

The key point of approaching metaphor through the lens of cognition is that this embodied way of viewing the world (relating everything to everyday life and experience) is habitual and so automatic that we are largely unaware of it. It occurs at the preconscious level. In the case of conceptual metaphors, therefore, language, is an indicator of an underlying way of thought.⁴⁴ This way of viewing metaphor deepens Jessica Wright's exploration in this special issue of Theodoret's use of the metaphor of the brain as a treasury of marrow. Theodoret can exploit three different “figurative paradigms” precisely because each is a variation of the same metaphoric concept. All three—the city as body (Platonic), the cosmos as body (Stoic), the Church as body (Pauline Christian)—map onto the same source domain (the human body). This is intuitive and natural. Everyone understands that the brain is part of the human body. As Wright delves further into how these metaphors are developed in Theodoret's thought—the skull is a citadel, the body circulates resources, the bishop is the brain of the church that distributes resources to the civic body—she in essence demonstrates that Theodoret engages in conceptual blending.⁴⁵ Blending, in which words, images and concepts are combined in a series of mental spaces to produce new meaning, is common when conceptual metaphors are employed. As Andreas Musolff has shown, this process can prove highly successful at circumventing reason and effecting intuitive conclusions in the brain of the listener.⁴⁶ That is, in addition to illustrating the theological and church-political point that he wishes to make, the metaphoric images that Theoderet employs from the medical domain serve quite literally to lead his listeners intuitively to his desired conclusion.

From here we turn to consider a suggestive link between medical metaphors as conceptual—how they can both reflect and encourage ways of thinking—and how medical metaphors can both reflect and influence moral decision-making. With regard to conceptual metaphors, morality, as we have already observed, is a commonly occurring target domain.⁴⁷ We also observed that, when thinking about morality, Health-Illness is a common source domain. In the previous section I discussed how medical anthropology encourages us to view the understanding of illness-health and care for the sick as socially and culturally informed. Here I explain in brief how experimental moral psychology, a growing discipline within the broader field of social psychology, helps us to unpack this further. As we will see, moral intuition plays an important role in the application of medical metaphors—particularly wounds, infection, gangrene, sickness and disease—to outgroups (e.g. heretics, Jews, barbarians, Christians, and later Muslims) in ingroup writings in Late Antiquity.⁴⁸ 

Moral intuitions are the subject of Moral Foundations Theory (MFT), a relatively new theory within moral psychology that is concerned with explaining how social groups cohere.⁴⁹ MFT is concerned with basic universal moral values that facilitate group cooperation and that are common to all cultures and societies, not with the specific religious or social values that groups aspire to live by.⁵⁰ The theory is built on a combination of exhaustive analysis of the anthropological literature in conjunction with experimental research. It argues that morality is a, if not the, primary socially-organizing force.⁵¹ A small number of basic values informs how individual human beings facilitate mutually beneficial cooperation and overcome selfishness. Moral intuitions derive from adaptive challenges that groups commonly face.⁵² The five moral intuitions or foundations that satisfy the criteria so far are: care/harm; fairness/cheating; loyalty/betrayal; authority/subversion; and sanctity/degradation.⁵³ The most significant for our purposes is sanctity/degradation.⁵⁴ The key adaptive challenge that gives rise to this moral foundation is “keeping oneself and one's kin free from parasites and pathogens, which spread quickly when people live in close proximity to each other.”⁵⁵ Suspicion of contamination or contagion is thus a key trigger for a plethora of related metaphoric concepts in the brain and associated behaviors.⁵⁶ Since cleanliness, purity, and hygiene are the responses required to keep the social group safe, healthy, alive, and intact, the conceptualization of something as contagious or polluting can elicit these same responses at both the literal and conceptual level. This is why in Late Antiquity heretics were both metaphorically and literally amputated (cut off through exile) from the Church, the body of Christ.⁵⁷ It is through the intuition triggered by suspicion of contamination or contagion that metaphysical or invisible contagiousness (e.g. of misfortune) readily becomes accepted as an ontological reality.⁵⁸ 

The same basic values that facilitate intra-group cooperation can facilitate inter-group conflict.⁵⁹ This is due to the degree of emphasis that a group places on each of the moral foundations. As Jonathan Haidt argues, the five moral foundations are responsible for “two common ways that cultures suppress and regulate selfishness, two visions of what society is and how it ought to work […] the contractual approach and the beehive approach.”⁶⁰ In the contractual approach the individual is the fundamental unit of value; in the hive approach, it is the group and its territory. This model further led Haidt to describe care/harm and fairness/cheating as individualizing foundations, in that they generate virtues and practices that protect individuals from each other and allow them to live in harmony as autonomous agents who can focus on their own goals. Whereas loyalty/betrayal, authority/subversion and sanctity/degradation can be described as binding foundations, because the virtues, practices, and institutions they generate function to bind people together into hierarchically organized interdependent social groups that try to regulate the daily lives and personal habits of their members.⁶¹ In the world of Late Antiquity, with its prevalent Christian discourse of heterodoxy/orthodoxy and anti-Jewish and anti-pagan polemic, MFT can help us to understand how the application to bishops of the metaphor of a brain that resources or regulates the health of the Christian body could activate the authority/subversion intuition and foster a particular (hivist) mindset.⁶² Delving into the realm of intuitive moral decision-making and the way this can both be reflected in, and influenced by, language distances us further from the older view of medical metaphors as figurative or as linguistic ornament.

Conceptual metaphors and intuitive moral judgments are related in that they both operate at the preconscious level in the brain and are automatic, seemingly natural, and intuitive.⁶³ When brought together, the insights of CMT and MFT into how language works in the brain strongly suggest that metaphors are not neutral, simply a way of illustrating something, but active agents in the mind of both speaker and listener. This has particular implications for how we approach medical metaphors. From cognitive linguistics we understand that medical metaphors tap into common experiential ways of viewing the world. The entailment of this is that we are required to treat source and target domains in medical metaphors as interconnected. From moral psychology we understand that medical metaphors can tap into primitive intuitions (e.g. authority and loyalty, or purity) that have both cognitive and behavioral consequences. That is, metaphoric language can both reflect thought and influence it, expressing in literal action.

These findings have several implications for how we approach and read the deployment of medical metaphors in Late Antiquity. Firstly, it opens up the possibility that language of health and disease can, both intentionally and unintentionally, tap into preconscious moral intuitions that trigger intuitive moral judgments. These in turn have cognitive and behavioral entailments. What those entailments are will, as we explained in the preceding section, be influenced by the cultural context. Secondly, there is a strong and natural link, via morality and illness-health discourse, between health, morality, and religion. As a consequence, concepts of pollution (e.g. blood-guilt, the spread of death through the odor of corpses) and purification go hand in hand with the notion of illness as punishment by God or the gods, sin as a sickness, and similar concepts.⁶⁴ For the society in which these transferred moral concepts are prevalent, these ideas are as real and as much a part of everyday common sense as the actual experiences of illness and health on which they are conceptually and intuitively predicated.

This leads us into a third shift, through which we are increasingly recovering a view emic to the Greek and Roman worlds from which Late Antiquity emerged, and which encourages us to view language itself as part of medical therapy. The key here lies in the ancient view of medicine and philosophy as sibling worlds of knowledge, the one focused on the health of the body, the other on the health of the soul.⁶⁵ Of particular importance for the reading of medical metaphors is the implications of the twinning of philosophy and medicine for how the two became interconnected and entwined in therapeutic practice.⁶⁶ The work of Michel Foucault,⁶⁷ Pierre Hadot,⁶⁸ Martha Nussbaum⁶⁹ and others has brought into prominence the practice of philosophical therapy, germane to the domain of moral philosophy and, as we are increasingly coming to appreciate, intimately entwined with the third of the three ancient medical therapeutic modes, regimen.⁷⁰ In a view that twins medicine and philosophy fasting, vigils, and sleeping on the ground are more than just bodily practices; they are critical to the production of mental and psychic health. At the same time, mental and psychic health is firmly rooted in the body. Because there is a sympathetic relationship between the body and soul, diet and exercise are good for the soul, just as the right ordering of the soul is good for the body.⁷¹ This is especially the case as we move into Late Antiquity and observe the rise and promotion of moderate urban asceticism, with its further entanglements of medical and philosophical therapies.⁷² We see these principles highlighted by Jared Secord and John Penniman in their articles in this special issue.

Philosophical therapy is in turn intimately entwined with the practice of rhetoric and the formation of the ideal person (usually the male citizen) through the shaping of their soul (psychagogy). Gorgias conceives of this in primarily medical terms—the power of persuasion is a drug (pharmakon) that can both heal and harm.⁷³ As the preceding section suggests, this conception of rhetoric that directs and forms the soul as a medical-therapeutic tool should not be assessed as a simple medical analogy. Recently Gorgias’ conception has inspired an analysis of contemporary rhetoric that argues that, in light of recent neuroscientific research, emotional political rhetoric can both be addictive and cause literal brain trauma in the listener.⁷⁴ That is, because the brain is embodied and linguistic concepts are instantiated at the neuronal level, certain kinds of rhetoric can have a discernable bio-medical effect. The claim that rhetoric can have a literal physiological effect echoes the claims of Hellenistic and Roman moral philosophers and, following them, Christian preachers in Late Antiquity.⁷⁵ 

In light of all of these interconnected culturally normative sets of ideas (philosophy and medicine as sibling therapies, ascetic practice as regimen for both body and soul, rhetoric as therapy) the slippage between the literal and metaphorical in late antique medical metaphors becomes particularly evident. The intimate and thoroughly medically-grounded link between digestion, body, mind, and soul, helps us, for instance, to make sense of why John Chrysostom uses a different eye-disease metaphor than Clement of Alexandria when explaining mystagogy to his initiates. In her article in this special issue, Emily Cain demonstrates how Clement draws on a particular school of medical knowledge and ophthalmic surgery to explain how through baptism the darkness that obscures the eye of the soul is removed so that it can henceforth see divine truth. In Catechesis 4, John Chrysostom draws on a different school of thought and different eye complaint to explain how in baptism God's grace removes the humor (gum) that darkens the eye of the mind, so that the initiate henceforth can clearly see the difference between wickedness and virtue.⁷⁶ The eye disease he references is peculiarly suited to his psychagogic emphasis on self-control and moral formation. Similar to Asterius of Amasea's “mist that satiety usually pours down over the eyes,” which fasting removes, leaving the eyes clear and undarkened,⁷⁷ the gummy excretion (λήμη) that John Chrysostom adduces as darkening the mind's eye prior to baptism has, according to the Hippocratic writings and Galen, its origins in overeating and inadequate digestion.⁷⁸ It is no accident, then, that, when talking about how the initiate through baptism becomes a new creation, in the immediately preceding section of Catechesis 4 he asks: “How is it not new and paradoxical when the person who up until yesterday devoted their time to excess and gluttony suddenly embraces self-discipline (ἐγκράτεια) and a simple lifestyle (λιτότητα διαίτης)?”⁷⁹ The line that John Chrysostom draws is clear. For an audience steeped in the same traditions, the connection between bodily practice and clarity of sight, both physical and spiritual, would have been self-evident. Clement, as Cain explains, is concerned with a quite different objective—not with the treatment of sin as a sickness, but with the self-perception of the initiate as a participant in a select social group with superior knowledge.

When we link the point just made with the study in this special issue of Gregory of Nyssa's catechetical oration by John Penniman and Jared Secord's adduction of the medical ideas that inform Christian athletic metaphors, we arrive at one further insight concerning the use of medical metaphors in Late Antiquity: in this period religion, medicine, and philosophy are so intertwined that Christian theology itself can be highly medicalized. This point is argued persuasively by Gregor Emmenegger.⁸⁰ As he shows via three case studies, some theological concepts in particular—in this case ones that cluster around women, conception and birth—draw naturally on medical and natural-philosophical traditions. In his first case study, the masculinization of Mary Magdalene in gnostic texts, the Galenist one-sex or inverted-sex model of gender is necessary for understanding why in certain texts Mary develops from a woman who must become masculine (Gospel of Thomas) to a purified manly gnostic (Gospel of Mary) to the personification of Wisdom and Jesus’ consort in the Gospel of Philip.⁸¹ In a second case study Emmenegger turns to incarnational theology and the conception of a divine child via the Holy Spirit. Here he finds ancient, especially Aristotelian, teachings on the embryo and how it acquires a soul particularly influential.⁸² In his final case study, Mary as mother of God and the virginal birth, Emmenegger explains why the statement “born of the virgin Mary” in the Apostle's Creed is neither metaphoric nor, to a Christian of the first few centuries, counter-intuitive. The roots of this doctrine are once again shown to lie in ancient gynaecology and natural philosophy.⁸³ 

The implications of studies of this kind are significant for how we approach medical metaphors in explicitly theological writings. In explaining how the theology developed, Emmenegger's exploration traverses gnostic and “heretical” as well as “accepted” writings. A key element in his argument is the role played by apologetics in defending against problematic theological positions that arose as a result of the adoption and adaptation of pervasive medical and natural-philosophical theories. Individual Christian writers, he shows, adopted and adapted different medical theories differently to suit their own emergent theologies. In this respect, when for instance we encounter different medical metaphors concerning the same liturgical ritual in separate Christian texts, as in the case of Clement of Alexandria and John Chrysostom, we should see this as a prompt for delving deeper into the different theologies—and different medical theories inherent in those theologies—that inform the choice of metaphor. The same applies when individual Christian writers discuss theological ideas that engage the human body, such as asceticism, the nature and function of the soul, or anthropology. The medical metaphors they employ, we should consider, function as a window into their personal theological thought world and provide important clues as to how those thought worlds intersect with, and differ from, each other across a spectrum of Christianities in Late Antiquity. Paying careful attention to the choice of medical metaphors across texts and authors matters and can offer insights on a number of levels.

One final implication of viewing medical metaphors from within the context of the intimate relationship in Late Antiquity between medicine, philosophy, and religion is that we need to consider the genre of the texts in which medical references and metaphors appear. Where protreptic and the formation of the listener is involved—this is particularly the case with sermons and homilies, but letters and treatises can also fall into this category—the fact that these texts may well have been conceived of by both author and listener as therapeutic tools challenges us to consider precisely how the audience would have responded to the medical language. Acceptance of this has a further entailment. It requires us to expand how we categorize medical literature produced in Late Antiquity. It calls us to consider that all texts that contain medical language and medical metaphors have something to say about the conceptualization of medicine in Late Antiquity and its practice, regardless of whether their author is a physician, philosopher, or priest. How we view medical metaphors and how we identify a text or practitioner as medical changes when we acknowledge how blurred the boundaries were between medicine, philosophy, and religion.

The investigation and analysis of medical metaphors in the writings of Late Antiquity and their contribution to the history of medicine are still more or less in their infancy. The shifts and approaches outlined here, together with those exemplified in the other articles in this issue, are, most likely, just the beginning of multiple ways of approaching medical and metaphoric language that will increasingly complexify our understanding of the usage of medical metaphors and their impact. Even so, the three ways of viewing and analyzing medical metaphors outlined here are highly suggestive. Firstly, they call on scholars approaching the history of medicine to take into careful account the ways in which medicine as a mode of knowing and its associated practices are shaped by society and culture. Secondly, they call on us to take into account the conceptual world that gives meaning to medicalized language. Thirdly, they challenge us to consider how language itself both passively reflects, and actively influences, cognition (language as mirror and agent). In this respect they call on us to explore what medical metaphors say, not just about how the author of a text or their community viewed the world, but also about how the listeners as individuals and as community received it. As we progress along these paths, we move further and further away from what was once the prevailing view—that medical metaphors in these texts play no larger nor more complex role than that of illustration or ornament.