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Wednesday, September 17, 2014

Defining Pneuma

History of Medicine and Sexuality: Sources and Transmission

This following is an excerpt from my essay on “Medieval Conceptions of Pneuma and its Relationship to Sexuality and Sex Difference: From Arabic to European Philosophy and Practice,” in Lebenskraft and Radical Reality 1700-1900: The Soul-Body-Mind Question in German Thought and Literature. John A. McCarthy, Heather Sullivan, Stephanie Hilger, and Nicholas Saul, eds. Amsterdam & New York: Rodopi Publishers, forthcoming.

Defining Pneuma

The idea and definition of pneuma, most often translated into English as “vital heat” or “life-bearing spirit,” or even “vital power,” was described by Aristotle in a number of his works.[1] In De generatione animalium, Aristotle explains the central role of innate pneuma to the “perception, mental activity, and physiological vigour” of all living creatures.[2] The text also connects pneuma to conception as well as how the “faculties of the soul are transmitted to offspring.”[3] The notion of innate pneuma is embedded in a system that connects the non-human, the “astral” (or aether) element of the stars, with the human, as it is drawn into the body through respiration and is the source of vital heat. According to Aristotle, “pneuma is already present in semen and is an analogue of the astral element, which is responsible for the fertility and life-generating power of semen.”[4] Aristotle thus draws a close connection between these two elements, the role respiration plays in feeding the “internal fire” of living creatures, and the special role that sperma plays as a unique foam-like substance which provides the “form” in the act of conception.[5]

The role and purpose of pneuma reflects as well the humoral principles established by Hippocrates, Aristotle, and later in greater detail by Galen. Humoral theory informed the explanatory principles for medical practice for the Greeks and Romans, and then later the Muslims, and then Christian Europeans through at least the sixteenth century and in a more limited way into the nineteenth century. Humoral theory is a worldview based on the relationship between the macrocosm and the microcosm and the interaction between the four primary principles in the body. In brief, the theory held that the body contained four basic substances –humors—which, when in balance, made for a healthy individual. These bodily humors are black bile, yellow bile, phlegm, and blood, and they were thought to be directly related to the four earthly elements, earth, fire, water, and air (respectively). Each individual had his or her own temperament (Melancholic, Choleric, Phlegmatic, or Sanguine) depending on his or her basic humoral makeup; this temperament might shift as the balance of one’s humors shifted, but essentially one was thought to be fundamentally one kind of temperament or another.

Just as the humors dictated a person’s temperament, all ailments and diseases were believed to be caused by an imbalance of humors in the body. These imbalances would be addressed through diet, exercise, and medicinal remedies designed to bring the body’s humors into balance. This might include purging (blood, excrement, phlegm, etc.), fumigation, applying heat or cold, and the use of herbs and other substances thought to be associated with counteracting or restoring the deficit humor. Treatments would also be determined based on macrocosmic elements that were associated with the humors and the elements, including seasons and astronomical and astrological influence.[6]

Each humor is also associated with a particular organ and, in a tripartite pneumatic frame, certain organs were paired with one of the three pneumas. The theory held that food is digested and transmitted (from the stomach) to the liver, where it is transformed into blood with the natural pneuma (spiritus naturalis, natural spirit). It is then imbued with the vital pneuma (pneuma zotikon, vital spirit) as it passes to heart; the vital spirit is imbued with the air from the lungs, drawn in through the air inhaled from breathing (also known as aether or astral air as described above). The psychic pneuma (pneuma psychikon, animal spirit) is formed as the vital pneuma moves to the base of the brain, and then the arterial blood moves through the brain’s vessels in a kind of distillation process. The pneuma then moves outward in arteries and veins to all the organs.[7] In this schema, the natural pneuma is associated with yellow bile, fire, and the liver (or sometimes the gallbladder); the vital pneuma is associated with blood, air, and the heart; the psychic pneuma is associated with phlegm, water, and the brain. Further, pneuma has associated with it rational, spirited, and appetitive “principles in the brain, the heart, and the liver respectively” as the function of pneuma changes and is elaborated depending on where it is located in the body.[8] It should be noted, however, that there is some variation amongst theorists in these associations and pairings, as the different organs are sometimes connected with different humoral qualities—and note, too, that the humor associated with black bile has no specific (tripartite) pneuma associated with it.

Not surprisingly, the theory of humors was central to medieval medical practices and understandings of sex differentiation, conception, and sexual desire, and the theory supported each culture’s view of women as the inferior sex by ascribing to the female (or feminine) the weaker or inferior temperaments. The physiology of the body was thought to consist of a combination of hot, cold, dry, and wet, and these elements were in turn associated with male or female characteristics. It was hypothesized that humans, as well as animals, consisted of the elements of fire and water (fire, hot and dry, and water, cold and wet). Males were considered hotter and more perfect. Women were considered to be essentially colder than men, and those temperaments that were associated with colder elements were considered more feminine in nature. Likewise, the theory of conception generally, and the relationship of pneuma to humoral theory more specifically, hierarchized the role of the male both socially, in terms of gender roles, and biologically, in terms of their role in conception, particularly in the formation of sperm. The association of some elements with more masculine or hierarchized characteristics naturally extended to the nonhuman macrocosmic elements of earth, water, air, and fire, as well as the celestial bodies and seasons.

The relationship between pneuma—in the broadest sense of the term—and air in the functioning of the body, the relationship between pneuma and the soul, and the relationship between pneuma and conception are examples of ways in which the philosophical, physiological, medical, and even spiritual systems were shaped by a male discourse that viewed women and feminine characteristics as weak, imperfect, irrational, passive, inferior, etc. As seen above, the air (or aether, the cosmos) sets in motion pneuma throughout the body (along with digestion). Air, variously described as aer, aither, pneuma, phusa, and anemos, brings with it a gendered quality, and one that emerges in the role of pneuma in sexual desire, sex differentiation, conception, as well as in relation to the soul.[9] Most clearly this gendered connection can be seen through a binary system famously attributed to Aristotle, that delineates (among other binaries) the two fundamental principles of active and passive; these principles apply to pneuma and its relationship to the soul and bodily function.[10]

In this schema, the passive is a “quality-less substance or matter”, and the active is identified as “the cause, god, reason, fate, soul, or pneuma”, where pneuma is the “active principle” that “pervades everything” and holds everything together.[11] Pneuma was also considered to be connected to the macrocosmic: “just as our soul, being air (aer), holds us together, so does pneuma or air (aer) enclose the whole world.”[12] For example, the (clearly masculine) power of the wind, or air is, as Geoffrey Lloyd points out, “worked out especially in connection with sex […] the winds were reputed to be able to impregnate mares.”[13] This (metaphorical) image that connects the power of air/wind with conception is found in texts from Plato, Homer, and then later Aristotle, and Galen. The various meanings of pneuma also include “breeze and breath/respiration but stretch to spirit, inspiration, and eventually to […] Holy Spirit” all of which are associated with masculine characteristics.[14] The ancient writers such as Hippocrates, Aristotle, and later theorists, saw these elements both in terms of sex differentiation as well as in relation to the soul. This combination of elements also accounted for the composition of the soul: “Soul, psuche […] is a blend of fire and water,” though the blending is different in the case of males and females.[15] Further, Aristotle viewed the soul and the body as interconnected, where the soul is the activity of the body.[16] Numerous philosophers would find divine presence in pneuma, which they saw as sharing both the cosmic, divine, and psychic principles.[17] Thus the role of pneuma in bodily function, reproduction, and the soul was intimately tied to concepts of active and passive, form and matter, male and female.

Similarly, the process of distillation noted above in relation to pneuma in the body had an analogy in the production of sperma; this theory privileged the role of male sperm.[18] There were, of course, debates over the centuries, first amongst Greeks and Romans, then later in the Muslim, Jewish, and Christian worlds, about the nature of sperm and the role of female versus male seed in conception. But the general consensus saw sperm as “man’s purest blood” and the “residue of the last coction” which, as it makes its way from the brain towards the sexual organs through veins and arteries, finally “undergoes one final metamorphosis” in which the purified “moist sperm accompanied by pneuma is ejaculated.”[19] This view connected with later discussions in the Middle Ages, first by Arabic, Jewish, early Christian, and then later Christian European thinkers, philosophers, and scholars.


[1] Bos and Ferwerda, p.2. note 4;  Friedrich Solmsen, “The Vital Heat: The Inborn Pneuma and the Aether,” The Journal of Hellenic Studies, 77. 1 (1957), 119-123 (p.119).
[2] Bos and Ferwerda, p.2.
[3] Solmsen, p.119.
[4] Bos and Ferwerda, p.1.
[5] Bos and Ferweda p.9-10. This theory of sperm was established in earlier works by Plato Diogenes, and Empedocles (Slomsen, pp.119-120).
[6] Jacquart & Thomasset, pp.48-86. See also Peter E. Pormann and Emilie Savage-Smith, Medieval Islamic Medicine (Edinburgh: Edinburgh University Press, 2007), pp.41-79.
[7] Jacquart & Thomasset, pp.48-49; Jacalyn Duffin, History of Medicine: A Scandalously Short Introduction (Toronto: University of Toronto Press, 2000), pp.43-45; Geoffrey Lloyd, “Pneuma Between Body and Soul,” Journal of the Royal Anthropological Institute, 13.1 (2007), 135-146 (p.143); C. E. Quin, “The Soul and the Pneuma in the Function of the Nervous System after Galen,” Journal of the Royal Society of Medicine, 87 (July 1984), 393-395 (p.393).
[8] Lloyd, pp.142-143.
[9] Lloyd, p.136; Lloyd does an excellent job articulating the history, subtle variations, and uses of this term as well as the other, related, terms referred to in this paper: aer, aither, pneuma, phusa, and anemos.
[10] Lloyd also includes a discussion of the Stoics and pneuma, and how those theories connect to later Galenic and the Arabic texts (p.142).
[11] Lloyd p.142.
[12] As quoted in Lloyd, p.145, n. 9
[13] Llyod, p.136.
[14] Lloyd, p.137.
[15] Lloyd, p.140.
[16] Lloyd, pp.140-141.
[17] Solmsen, p.122; the Stoics, Aristotle, Diocles, etc. shared this notion. In addition, we see this connection in Virgil’s Aeneid VI, where Virgil connects aether, or pneuma as “the home or essence of the soul” and “employs freely one or the other of our concepts as a symbol of man’s divine origin” (Solmsen, p.123).
[18] Jacquart and Thomasset, p.49.
[19] As quoted in Jacquart and Thomasset, p.60. This quotation is a translation of a late fourth century Christian philosopher and Galenist, Nemesius, bishop of Emesa, from (what is now) Syria. Interestingly, Nemesius is noted by Philip van der Eijk as an early practitioner and theorist of addressing the problem of the relationship between mind and body through associating different parts of the brain with different functions, and by exploring “the structure of the human body, the position and function of its constituent parts, and the relation between the body and the soul (or the mind) in complex activities such as sense perception, voluntary movement, imagination, memory, thought, desire, and the emotions. The presupposition of the work is that the human soul-body composite is as good as it possibly can be: the body and its parts serve as an ‘instrument’ (the Greek word is organon) for the mind and its functions.” Philip van der Eijk, “Nemesius of Emsea and Brain Mapping,” The Lancet, 372.9637 (9 August 2008), pp.440–441 (p.440).