Having spoken of the scientific attitude in pre-modern Japan through the eyes of Ninja, who supposedly possessed supra human knowledge of the human behavior and natural medicine, it is now time to delve further into the Buddhist conception of how the world operated. In the first part of my research, I discussed the ways in which a particular group of war specialists in Japan developed their own system of scientific knowledge, prior to the Western contact, and thus making it distinctly Japanese. This group of war specialists, Ninja, studied extensively on human behavior and psychology but my studies have shown that they had poor understanding of medicine and lacked the interest as well as the philosophical rigor in discovering the causes of illness, which in turn led them to essentially rely on nothing but the placebo effect in curing sickness. Hence, in this second part of my research into the history and philosophy of science and medicine in pre-modern Japan, I will look at the broader perspective on medical theory and attitudes towards illness amongst the monastic doctors as well as the commoners prior to the importation of the Western science. In particular, my interest is in the etiology of various types of sickness and how people in Japan dealt with the symptoms. It is of course not possible to speak of purely Japanese practice, since Chinese influence is everywhere seen. However, my study will show that Japanese Buddhist philosophy nevertheless developed distinct features unique to Japan, perhaps as a result of the synthesis of the Buddhism with the Japanese native religion of Shintoism. It is in this context that I will be discussing about the medical philosophy proper to Japan, which must have existed in order to account for sickness and beliefs unique to the culture that were not found in the continent. In this article, I will focus on the supernatural yet real causes of illness according to the Shinto-Buddhist philosophy. Indeed, in the pre-modern period Japan, the causes of illness were explained in terms of the Traditional Chinese medical philosophy, Taoism, and Buddhist medical theory. According to one such view heralded by the etiology explained in the most widely studied book, Makashikan, written in the 6th century by the founder of Tien Tai school, Chigi (538-597), the major causes of illness were six in number. They are 1) the imbalance of four elements, 2) excessive eating and drinking, 3) lifestyle related diseases, 4) daimon, 5) evil spirits, and 6) deeds in the previous life. Of these, the first three are natural causes and thereby can be treated with the medical knowledge. On the other hand, the latter three are supernatural causes and cannot be treated except spiritually, i.e. one must follow the path of the Buddha. I will focus in particular on the daimon and evil spirits in the field of medical thought in pre-modern Japan. I will unveil the familiar concepts of Oni and Yokai in light of medical context in the history of Japan, and analyze the ways in which these supernatural forces came into the medical philosophy in the Japanese monastic medicine.  Taku Shinmura, Medical History in Japanese Buddhism, 34-36.
Daniel Sennert (1572-1637), a professor of medicine at University of Louvain worked largely on the early seventeenth-century intersection of matter theory and life sciences, focusing on and developing a corpuscular interpretation of the origin of life to explain biological, normal generation (univocal generation) as well as spontaneous generation (equivocal generation). This chapter examines the univocal generation first and then his theory of spontaneous generation, which Sennert argues along with Liceti that there is no such thing as strictly speaking abiogenesis.
Sennert first asks whether souls can be produced. He answers in the negative, and argues that souls are multiplied but not produced or generated. This is because for him souls can be (and were) created by God at the beginning, and God as the first and universal cause is the only agent who can create souls. Having ordained nature to perpetuate the course of generation and corruption, God gave the second causes a capacity to produce the generation of all things from the very first soul simply by multiplying themselves. This is an argument against those who hold the eduction of forms – for even if forms are drawn out from the potentiality of matter, the question of where they originate is left entirely unanswered. For this reason, Sennert advances the idea that all forms can multiply, just as is read in Genesis: “Be fruitful and multiply.” That is why he thinks that souls are not produced anew but are only multiplied in the generation of natural beings. Further, he also differs from Liceti with regard to the forms in that while the latter taught that forms are generated from a certain “rudiment” of form preexisting in matter, Sennert does not accept the idea that the form, first possessing a generic nature, then receives its own specificity from an external agent, and criticizes the opinion since Liceti did not reveal what this rudiment really is.
For Sennert, a simple quality like heat cannot produce a form, which is a divine substance. He thus concludes that besides the disposition of matter something formal is needed in the seed as the cause of its action.
Now for Sennert, the plastic faculty is equated with the soul itself, which is for Schegk that which is introduced from the heaven after the pure motion exerted from the male parent to communicate the spermatic/plastic faculty into the matter. This spermatic faculty, for Schegk, is replaced by the human soul that already preexists, and disappears after this replacement with the soul. But, Sennert asks, if the spermatic faculty gets replaced with the soul, and acts like the soul itself, why not call this spermatic faculty a soul, without introducing unnecessary terms such as plastic faculty, spermatic faculty, instrumental potentiality and productive actuality, etc? For Sennert, this plastic faculty, or the plastic reason-principle, is identical to the soul, which is not the instrumental but the principal agent of generation.
So for Sennert, the seed is animate and possesses a soul in itself. “[I]t is a very simple substance or a certain spiritus, in which the soul and the plastic force immediately reside, and contains within itself the Idea of the organic body from which it has fallen, thus possesses the potentiality both to form an organic body similar to that from which it has fallen to prefect itself into an individual of the same species as [that] of the parent.” For Sennert, spiritus is not the principal cause of generation as it is for Fernel, but merely an instrumental cause of the soul. The soul uses the spiritus residing in the seed and, as far as the spiritus is in the seed, the soul is in its own subject. But when the spiritus goes away, the soul cannot remain in the seed anymore and the seed becomes sterile. Further, Sennert makes a radical break from the traditional thinkers in that Sennert recognizes only one soul throughout – the humans have from the beginning one rational soul, which has the vegetative, sensitive and intellectual faculties, which is transmitted through the seed.
Sennert argues in the manner of Liceti that the equivocal generation too is realized by an internal principle lying hidden in matter, which does not differ from non-spontaneous generation in which the principle of generation is also hidden in matter and inaccessible to human sense-perception. Indeed, Sennert goes on to say that spontaneous generation too is caused by a univocal agent, for living beings that do not reproduce themselves through the seed in the literal sense still possess something that corresponds to the seed. This something contains not the soul but the principle or the form which begins to carry out the functions of the soul when it finds suitable matter. In this way, Sennert explains that every corpse of plants and animals can seemingly produce worms and maggots spontaneously, when in fact it is this particular form which will manifest itself as a soul in a certain condition. This is why Sennert explains that when Aristotle said “[t]here is water in earth, and pneuma in water, and in all pneuma is soul-heat, so that all things are in a sense full of soul,” Aristotle does not mean that all things are animate, but that there is in all things such a hidden entity which becomes manifest and executes the functions of life when it encounters suitable matter.
This hidden entity, which he calls a seminal force, is the internal principle of generation, i.e. seminal principle. But after a great change in matter, according to Liceti, because of the loss of the heat that sustains the soul, the soul degenerates into another inferior species. But Sennert does not accept the mutation of the form, and rather he opts for the multiplicity of the forms in a subject, calling the one dominant and the other(s) subordinate forms. When this dominant substantial form disappears, one of these subordinate substantial forms replaces it by taking over its functions. Sennert further argues that this seminal principle is present in a subject even if it is divided into the minima or smallest atoms, which further supports his view that all things are full of souls. So in the case of living beings that are seemingly spontaneously generated, their seminal force can persist even down to the level of atoms until the time when it finds a suitable matter from which it establishes an animate body. So the atoms of living beings are essentially corpuscles composed of primordial atoms for Sennert, and although the soul residing in one atom may be too weak to generate anything, several atoms can be united, which allows the souls contained therein to be gathered and become more powerful.
In recapitulation, whether it is called “seed,” “seminal principle,” or “soul,” there is first some entity that comes from the corpse of living beings and lies hidden in matter. So nothing is really generated spontaneously but everything is generated by its own soul or at least by this seminal principle which corresponds to the soul analogously. And when this entity is placed under suitable conditions, and stimulated by ambient heat, it begins to perform the functions of life.
The soul’s vehicle was no longer conceived as the spiritus itself but as an atom which is informed by its internal soul or the seminal principle corresponding by analogy to the soul, while the spiritus was clearly seen as being composed of atoms. So the Sennert’s idea of the seminal principle as the atom’s internal soul was made through his corpuscular reinterpretation of the soul’s vehicle. He then developed the idea of living corporeal corpuscles, which are scattered around the world and which carry the soul or the seminal principle, thus guaranteeing the continuous emergence of life. For Sennert, one atom, derived from living beings, has its own soul just as one atom of inorganic beings has its own form. Although Sennert borrowed the concept of the seminal principle from the concept of seeds, developed by a Paracelsian philosopher Severinus, it was Sennert who explicitly connected it to the atomism, hence playing the central role in understanding the development of matter theory in the advent of modern science. Thus, Hirai argues that Sennert is the great synthesizer of the concept of seeds with revived atomism, tracing back the origin of Gassendi’s idea to Sennert.
 Sennert quoted in Hiro Hirai, Medical Humanism, 157. “…it is a vain fiction to say that the generic nature is a rudiment of form and, as it were, a semi-form. It would follow from this opinion that like does not generate its like. Since the specific form gives each thing its own nature but not a generic nature, if the parent should only provide the matter in which the generic form exists, i.e., a rudiment of form or a semi-form as Liceti says, then it would be an external agent like heat that would introduce the specific difference.”
 Sennert quoted in Hiro Hirai, 159-160.
 Sennert quoted in Hiro Hirai, 163. “…the soul can be in some matter after yet another way without informing or vivifying this matter this matter or providing the actions proper to this living being. Thus the seeds of plants and animals can reside in water and earth, the soul [can reside] in these [seeds] without informing or vivifying water or earth.”
 Aristotle quoted in Hiral, 164. See also Sennert’s comment quoted on the same page. “To be sure, as Aristotle teaches, animal heat and especially that kind of heat that possesses the adjoined soul are truly in this whole part of the inferior world (earth, water and air). [They exist], however, not as their essential part or essential attribute because earth and water are cold by their nature and because neither earth nor water are informed by the soul. But [they are] as a thing put in a place or in a vessel, without doubt because earth, water and air contain the living beings’ corpses, parts and excrements in which there are atoms and corpuscles possessing a soul.”
 Sennert quoted in Hiral, 169. “Indeed, the soul of one single atom is so weak and it can neither vivify and inform the matter of the mushroom nor perform what can be done by the souls, gathered from many [souls], of numerous atoms united into one body.”
Chapter 5 discusses the theory of spontaneous generation by both the Renaissance Platonists such as Ficino and the Italian philosopher and scientist Fortunio Liceti. On the one camp, Platonists argue for the abiogenesis as evidence for the theory of universal animation and the existence of World-Soul, while on the other camp, a quasi-Corpuscularian doctor Liceti, while agrees that the World Soul is a remote cause of the life on earth, sees the mechanics of spontaneous generation as an argument against views held by Ficino. While various ideas are examined in this chapter, essentially, this chapter focuses on the views expressed by Ficino in Platonic Theology and by Liceti in De Spontaneo Viventium Ortu published in 1618. In particular, the focus is on the fourth division of the first book of De Spontaneo (chapters 68-151), where Liceti examines the views advanced by three groups of people who advocate the doctrines of the World-Soul and Ideas. The first group Liceti considers is the Junior Planotinists, followed by the views of the Major Platonists, ending with those of Ficino.
I: Junior Platonists
Philoponus, Virgil and Macrobius, identified as Junior Platonists, hold the view that the souls of all living beings are generated by the World Soul, and the efficient cause of spontaneous generation must be attributed to this universal soul of the world. To this, Liceti disagrees and argues that life is given to human beings by the human soul and to other beings by their own souls that the body of a living being which has not yet received its own specific soul cannot have life in actuality. In other words, life comes to the body only by its own soul, and it cannot come by the soul of the universe. Indeed, Liceti argues, it is not the World-Soul but the parent’s soul that is the immediate and particular cause of the generation of offspring of the same kind. This makes sense especially since Liceti views the World-Soul as God the Creator, and although God is a common and remote cause, God is not the immediate agent in generation of living beings born in putrefied matter. Liceti thus concludes that spontaneous generation requires another immediate agent, lying hidden in the matter from which these inferior beings are spontaneously born.
II: Major Platonists
Major Platonists, such as Cristoforo Marcello, argues that the immediate agents lacking in the Junior Platonists are the Ideas. This is because it is obvious that these inferior beings that are spontaneously generated do not have any other agent through which they might obtain their souls. So it seems to follow that these beings are directly produced by the particular Ideas procreating their own souls. This agent cannot be identical with the product, so there must be another agent by which the particular form or soul of living beings is procreated. But no immaterial agent except the Ideas of the souls of the living beings have an essence similar to these souls. From which, Marcello concludes that the souls of spontaneously born living beings are produced by Ideas as the particular and immediate agents of their generation.
But Liceti argues that generation is a physical action, and it requires by direct contact through movement. But because Ideas do not act physically, this Idea or the intellect cannot assume the role of a physical cause in natural generation. So even the inferior beings cannot be generated by these immaterial Ideas. Further, Liceti adds that since the forms of natural beings cannot exist without matter, they are material and perishable. And in this way, they differ from Ideas, which are totally immaterial.
Liceti in his turn argues that spontaneously born living beings are generated by a “congeneric” agent residing in matter. Just as Aristotle held, for Liceti, living beings can be generated but forms cannot. Forms in fact are lying hidden in well-disposed matter before the generation of these beings, and they become “life-giving forms” and are given as their souls. For Liceti, as we will also see in Sennert later, nothing is generated totally spontaneously in the sense of abiogenesis. The form exists as a potentiality and a privation of a future form, possessing an aptitude to receive forms in the course of change. Liceti concludes that the material and perishable forms cannot be physically produced by Ideas that are not of the same kind, but only by material forms of the same kind.
III: Ficino’s Earth’s Soul and Liceti
Ficino: the souls of living beings that are spontaneously generated are conferred upon matter by the soul of the earth or by that of the water through Ideas implanted in these souls. Finico argues for the Earth’s soul by an empirical claim, for he says that “we see the earth generating large numbers of trees and living creatures from their own seeds, and nourishing them and making them grow. Stones grow too like its teeth, and plants like hairs as long as they are attached by the roots,” and as soon as they are detached from the earth, they stop growing or die. In this way, he continues to argue that the proper causes are in the soul of the earth, which produces a vine by means of the natural Idea or rational principle of the vine, flies through the rational principle of flies, and so on. For “if art, which produces works that are not alive and introduces forms that are neither primary nor whole, has living rational principles, there is all the more reason to suppose that rational principles are present in nature, which does generate living things and produce forms that are primary and whole.” It is hard to draw a conclusion from this that living beings are spontaneously generated in the earth by the earth’s soul because there requires a definite and particular seed for the generation of particular things. It is in this context that Ficino introduces the concept of spiritual seeds, which are “life-giving seeds of everything” through earth and water. These seeds are enclosed by the vital nature, and this vital nature “takes elemental qualities and adds to them the precious varieties of colours and shapes and the vigor of life.” Further, this earth’s soul must of rational, since some of the earth’s animals do not lack reason and because the works of the earth are more beautiful than those of humans. So there must be, in earth and water, different parts – some are less pure and the others are very pure, and the former have irrational souls whereas the latter have rational ones.
Liceti: In contrast, Liceti observes that many living beings are spontaneously generated in human bellies or in cheese although matter serving the matrix of their birth is not touched by the watery or earthly sphere. From this, he argues that the immediate agent of their generation cannot be the soul of the elements. Further, Ficino counted only one soul for the earth despite a great diversity of living beings born out of it. This does not seem to square with the observation, and hence it is not possible to say that the one earth’s soul counts for all the diversity we see generating. Although Ficino argues that the earth nourishes living beings and makes them grow as if stones were her teeth and plants her hairs, Liceti again observes that the seeds that propagate these living beings do not come from the earth directly but from plants and animals of their own kinds. So the generation of these beings should not be attributed to the earth that carries these seeds, but to the seeds themselves. This is because these seeds are not produced by the earth but by the living beings themselves. So, he concludes that plants and animals live by their own soul and not by that of the earth. And because of this, Liceti denies that these inferior beings are generated spontaneously from the earth’s soul, and argues that such a soul, even if it exists, would be general at best and too remote to generate beings as their immediate cause. In order for generation to take place, a particular, more immediate cause must be present, which Liceti contends are seeds themselves.
Further, against the argument by Ficino that the earth has a living rational principle, Liceti argues that the nature is blind and ignorant and does not possess any Ideas but has only a similitude with the products. This is the same with the humans, who give birth to offspring by similitude of nature without any Idea of offspring. Further, Ficino argues that the pure parts of the earth are full of rational souls and the impure parts have irrational souls, but Liceti counters with the fact that the purest part of the earth is its center but there is no living being found there, while the most impure part is full of living beings. This then is an argument against Ficino’s claim that the earth possesses a rational soul. So, it is not true to say, as Ficino wants to argue, that nature executes its works through Ideas implanted in it and that the earth’s soul procreates a vine by means of the Idea of the vine. But it is the seeds that lie hidden in the earth that possess souls, which then stimulate the generation of inferior beings. Although Ficino argued similarly with his spiritual seeds, for Liceti, the seeds are made of material corpuscles, yet extremely subtle like a physiological spiritus and endowed with the rudiment of a future form. This is because Liceti believes that the form must share some corporeity with the matter in order to affect generation, as we have seen.
To the argument of Ficino that the elemental qualities, employed by the vital nature, account for the various colours and shapes of things, Liceti denies this, and argues that even with the help of the elemental qualities, they cannot produce colours and figures, but what gives them colours and shapes is the substantial form of these specific bodies generated and their souls.
 Ficino quoted in Hiro Hirai, Medical Humanism, 137.
 Ibid., 141.
 Ibid., 144. Italics mine. This is refuted by Liceti and later Sennert takes this to advance a need for the tria prima principles in order to account for the lack of ability for the elements to create colours and shapes.
[below is a summary of the chapters 1, 2 and 4 of Medical Humanism by Hiro Hirai. I chose these 3 chapters because of the thematic similarities they share, leaving out the chapter 3 on Schegk as somewhat distinct from the others.]
The chapters 1, 2 and 4 of this book examine the interpretations of the formative powers by various thinkers in the history of embryology. The humanist physician, Leoniceno gives his commentaries on commentators of Galen and offers his own interpretation of the issue. First of Galen, although he believed that there must be a supreme intelligence in the formation of the fetuses, he left it open whether it was to be equated with any kind of soul and did not speculate its origin. This led many commentators to hypothesize what this formative power could mean, and the identification or the explanation was in demand, as to what it is that is doing the formation of the fetuses, as opposed to merely nourishing the animal bodies. This is because the nourishing the bodies, which is the proper office of vegetative soul, does not necessarily require a forming principle.
Just as Hippocrates taught that the body’s natural heat is nothing but the mixture of the four elemental qualities (i.e. temperament), and just as Galen called the vegetative soul the animal’s natural heat, Leoniceno justifies his use of the term ‘temperament’ to mean both the body’s natural heat and the vegetative soul. Synthesizing Hippocrates and Galen, Leoniceno equated 1) body’s natural heat with 2) temperament and 3) vegetative soul. Hence, all these things are terrestrial origin and congenial to the animal’s birth. This in turn is termed as “inbred heat”. Here, Leoniceno did what Galen did not – although Galen believed the natural heat to be the vegetative soul, he believed it is of divine origin and did not think that it is the mixture of the terrestrial elemental qualities.
However, Aristotle recognized two different formative powers, according to Galen. One is formative power of homogeneous parts such as flesh and bones, while the other is the organization of heterogeneous parts such as hands and eyes. The former is mutative, for it forms organs and alters the shapes for fitting ones, while the latter is the formative cause proper as it forms particular hands and eyes proper to the species. For instance, formation of flesh and bones are universal to all animals, but what kinds of eyes or hands these animals have differ from species to species, and they become the distinct characteristics of particular animals. So Aristotle invoked a higher intelligence to this formative cause proper, and wondered if there can be a supreme intelligence of a creator, i.e. celestial cause. Leoniceno disagrees with the later commentators of Aristotle that Aristotle here was in fact invoking a celestial cause, and insists that it remains an analogy, for Aristotle says that this “inbred” heat is not fire and is the foam-like principle in the breath, i.e. spirit. Leoniceno is content that this vital/inbred heat is contained in the seed or the spirit, which is a certain vehicle, a subtle body, that carries the immaterial foam-like heat principle. Is Leoniceno then saying that this formative power is devoid of reason? No. Along with Simplicius, Leoniceno argues that this formative power is not irrational but rather co-responsible with the immediate causes of things that are generated and corrupted. What this means is that the formative power, although itself not of celestial origin, is subordinate or auxiliary to the celestial and intellectual causes, and this formative power is the concause with the celestial cause.
Of course, as was mentioned earlier, this is not what Galen held – for although he professed that he did not know the cause of this formative principle, he did believe that it must be of a divine origin, i.e. celestial cause. Jean Fernel picks out Galen’s view and tried to reconcile Aristotle (via Galen) with Plato, drawing upon the works of Marcilio Ficino. Fernel’s position on this would be that the vegetative soul (or natural heat) is essentially divine and that there is divine presence in natural and medical philosophy. Fernel indeed advances his argument as if Galen would have agreed with him, and to that extent, his argument is an elaboration of Galen’s view.
Fernel first argues that the form partakes in the divinity as opposed to the matter, which is nothing but the composite of the corruptible elements. The form thus equated with the divinity has more power than the four terrestrial elements, but precisely because it partakes in divinity, we cannot know the specifics of this power or where it originates. These hidden powers are called occult properties. Since these powers exceed the limits of natural philosophy, they are called divine and belong to the realm of the divinity. In this way, while Galen remained agnostic about the origin of the soul, Fernel attributed the notion of divine force to the natural beings on earth. Such divine force is wise and powerful, and responsible for the formation of living beings. This form is of necessity immortal, since it is not simply a congenial heat or a temperament (in which case, the soul/form would not be immortal because it would be nothing but a mixture of the four elemental qualities, and everything made out of these qualities are corruptible) but partakes in divinity. Such divine force must have the primary or the ultimate cause as the divine Creator, and neither whose substance nor his way of operation can be grasped by the human mind.
What is the essence of this soul/form? Fernel argues, according to the authority of Galen, that the soul is a completely simple, uniform and incorporeal substance. And in order for such incorporeal substance to have an effect on corporeal substance, it must be through some sort of semi-corporeal instrument, which is called pneuma. Notice that this is the breath or the spirit, a vehicle, discussed earlier by Leoniceno. Having argued that the soul is even more excellent than this pneuma, Fernel explains that pneuma is corporeal and essentially belongs to the body, whereas the soul is free of body and can subsist by itself. Further, upon the departure of pneuma, life ceases to function and life is restored when pneuma returns to the soul. So the soul does need this pneuma in order to function, although it can survive by itself. But at the same time, since the soul does not belong to the body and can subsist by itself, it is not a property of bodily substance (it can subsist by itself) or simply an incorporeal substance (it needs corporeal pneuma to function). It is somewhat half way between being a substance and being a property. What this means is that the soul is both incorporeal and subject to the needs of the body. It needs the body as its house to function, so it is not a substance in a complete sense.
How can the soul be both free and in need of body to function? If it is constrained by the body, it is not independent of body, and further, it runs the risk that the soul may be damaged when the host body becomes ill or poisoned. Fernel responds to this rather ingeniously that the soul does not suffer even when the host is damaged, but instead what is damaged is the chain of bonds that connects the soul with the body. So if a body suffers poison, then this union gets loosened, and when the union is broken, the soul flees itself, as if it had been freed from a chain tied to the body. This chain of bond is nothing but the pneuma, innate heat or spiritus. In this way, Fernel shows that the soul is not tied to the body in such a way that it needs the body’s constant aid.
Fernel then goes onto describe what power (dunamis) is, and explains that it is a potency of action and something the substance of a thing uses as a principle of action. In other words, it is in the thing but is different from the thing itself. It is that which emanates from the substance itself. Because this formative power/soul arises out of the substance from the very beginning, but is distinct from the substance itself, the vegetative soul must possess divinity as well. Although there are apparently two distinct powers in the tripartite soul, i.e. formation of the fetuses and the governance of the body, Fernels concludes with Galen that what molds the body also possess the ability to function each part of the formed body.
So the seed gives rise to this celestial mind and divinity, which is what the soul possessed. But if, as Galen argued, the soul possesses the force from the seed, such power cannot be of the celestial origin, and further it seems to suggest that the matter is actually an active principle itself, rather than the vehicle that carries such power. To the first worry, Fernel responds that Galen was speaking analogously to mean simply that this formative power is in the seed, and he was not actually saying that the force comes from the seed. Further, Fernel makes a careful point that the seed/matter is not identical with the formative power, but the celestial mind is placed in the seed. This also follows from the fact that Galen was speaking analogously about the relation between the force and the matter that emanates this force.
What exactly is then this spiritus/breath/pneuma? As has been said, it is close to incorporeal beings by virtue of being invisible. It is a means and instrument used by any substance devoid of body and hidden to human senses to communicate its force to the body. This is the way in which God communicates his power as well, through the use of the animus mundi, the World-Soul. The spiritus is said to be the basis of the soul and its forces, and in it lies the innate heat. The nature (or God) and the soul’s forces are enclosed in the spiritus, and this nature uses the spiritus and innate heat to form the living beings. So when the spiritus and the innate heat are lost, the chain of bond between the soul and the body disappears, and the life ceases to be. This nature being divine, it corresponds and shares with the element of the stars, i.e. the fifth element and aether. For Fernel, then, this aether provides the soul’s powers and implants the spiritus in natural beings, determining their form. While the composition and mixture of the elements can be the force of nature, the formation of specific organs and heterogeneous parts exceeds the capacity attributed to nature. Hence, there needs some other extraneous principle to guide through the formation of fetuses and living beings. In this way, Fernel attributed the cause of concoction to celestial heat, and not merely to the mixture of elements and their moderate heat. Without the celestial aid, concoction is noxious and destructive.
Such a conclusion has a medical significance, for it supposes a new etiology of diseases, because it is no longer just the imbalance of the four elements/humours that causes the diseases, but the elemental heat itself is conceived as something that is potentially bad for the body. The very idea that the formative power is endowed with a rational principle prevents Fernel from concluding that the spiritus is made up of the terrestrial elements. As the spiritus cannot come from the simple mixture of the four elements, it must be implanted into the natural beings at the time of generation, from then onwards directing the fetal formation and taking charge of the nourishment of the body. To this extent, then, the spiritus is said to be governed by and closely united with the World Soul.
Influenced by the Renaissance Platonism of Marcilio Ficino and his contemporary leading physicians, Fernel and Cardano, the royal professor of medicine at the Univeristy of Louvain, Cornelius Gemma (1535-1578) promotes Hippocrates as the leading figure amongst the “ancient theologians” along with Philo and Moses. This chapter gives the first analysis of the historical and intellectual context of Gemma’s Hippocratism based on the prisca theologica, or the ancient theology.
The followers of Galen tended gnerally to give a naturalistic account of Galen’s medicine, i.e. humoural imbalance within the terrestrial elements. Fernel, Cardano and Gemma, however, also adapted Ficinian Platonism on the basis of Hippocratic writings. Among the key notions in Hippocratic corpus, Fernel picked out the word “divine” used by Hippocrates to refer to something lying beyond the sphere of the four traditional elements. Because what is divine is not transient or destructible but supra-elemental, it must be something celestial. Fernel, as we have seen, tried to establish the consistent theme of Platonism both in Hippocrates and in Galen, but Cardano, as well as Gemma, rejects the Galenic medicine and leans heavily towards the medical corpus of Hippocrates.
Contrary to Fernel, Cardano was particularly interested in the Hippocratic writings that dealt with the celestial and atmospheric phenomena. In his book, On Subtley (De Subtilitate), he argues to establish a synthesis of two eminent ideas, i.e. the soul is nothing but a celestial heat (Hippocrates), since the heat of spiritus is analogous to the element of the stars (Aristotle). Arguing that the heat is the soul’s first instrument, Cardano explains that there must be the soul wherever this kind of heat is found, and wherever there is this celestial heat, one necessarily finds soul and life. This cosmic heat, for Cardano, is animate and endowed with intelligence. And because the World Soul is all pervading, the soul is said to be omnipotent in the entire universe. In this way, Cardano emphasized the celestial origin of the soul, arguing that the soul is immortal and cannot be corrupted, in accordance with Hippocrates, since nothing is corrupted but is only separated or dispersed. So for Cardano, Hippocrates figures as an ancient sage who knew and taught the very secret of the original constitution of the world and of the soul.
Similarly, Cornelius Gemma also calls upon the authority of Hippocrates by interpreting the notion of “something divine” in the manner of Fernel and argues that “the spiritus does not really differ from innate heat, just as the spiritus of the world does not differ from the element of the stars… [and] is the first instrument of a future form or soul. It connects the form to bodies as the spiritus is tied to these bodies by a carrier quality which intervenes. It is the same spiritus as that which perfects, connects, sees and understands all according to Hippocrates.” Gemma then divides the medical art into three parts:
① that which shows the actual state of things before our eyes (diagnosis)
② that which works through prognostication or prediction (prognosis)
③ that which deals with the hidden causes of actions in natural things (practice)
He continues to argue that the first two are inseparably tied together, for the medicine is intricately connected with prophecy, just as Hippocrates said that Apollo is the shared father of both medicine and prophecy. The one concerning the hidden causes of actions is explained by the “seven degrees of divinity” – the first of which is in the matter and the second is in the form of mixed bodies, whereas the third degree is found in the spiritus either through the Idea conceived in the soul as in the case of the formation of the fetus or through the action of celestial rays as are the works of innate heat).
[Q: what are the other degrees of divinity? What does it mean for a degree of divinity to reside in a matter or a form?]
For Gemma, the notion of spiritus as a universal knot of all natural things is an indispensable pillar in the structure of the universe as well as of human beings.
 Cardano quoted in Hiro Hirai, Medical Humanism, 111. “[i]t is evident that Hippocrates correctly said: the soul is nothing but that celestial heat. This also corresponds well to the opinion of Aristotle since he wants the heat of spiritus to have a certain analogy with the element of the stars. Indeed whether the heat is the soul or its first instrument, wherever there is this [kind of] heat, it is evident that the soul itself should be present; therefore [there should be] life too. For life is nothing but the work of the soul.”
 Gemma quoted in Hiro Hiral, Medical Humanism, 116.
 Ibid., 118. “Indeed the spiritus is the knot and tie of opposites and, by the kinship of its nature, looks at both sides to the same degree. So it is not surprising if it connects the soul to the body in a human being, celestial force with sublunary things in the exterior sphere, corporeal faculties with incorporeal faculties in both realms. And [it is not surprising either] if it mixes up among them the seminal reasons of all things which act and are acted on. Since [the spiritus] belongs to all, draws all through all, composing very different things into one species by the perpetual change of contrary movements (that is, attraction, repulsion or self-rotation), Hippocrates, more than divine, attributes this triple motion to the [spiritus] by really subtle signs in the first book of On Regimen and in the book On Dreams.”
Jacob Schegk (1511-1587) advanced the theory of the plastic faculty, which imposed much influence upon later thinkers such as Daniel Sennert, William Harvey and even Leibniz. What this plastic faculty is will be the main enquiry of this chapter. In this summary, I will follow Hirai’s paper structure and proceed by dividing Schegk’s work On the Plastic Faculty of the Seed into three parts, and review 1) what the plastic faculty is, 2) how it works in fetal formation and 3) its identification with intellect.
- What is a Plastic Faculty?
Following Aristotle, Schegk articulates that the term sperm is not the material cause
but the efficient cause of the formation of animal body. In other words, this term sperm, does not refer to the material liquid but a certain reason-principle, which he calls the plastic faculty. The efficient cause is further divided into two parts – one is the principal efficient cause, i.e. the agent in actuality, as in the male parent or the heaven, while the other is instrumental, which is this plastic faculty. We know that the male parent is, being actuality, animate and corporeal, and this faculty or the sperm cannot be animate and corporeal because then, its ontological status is identical with that of the parent, and is no longer identified as instrumental but principal. But it cannot be inanimate either, because what is totally inanimate cannot produce what is animate, the latter being nobler than the former. This leads Schegk to offer a third option, that is to say, this spermatic faculty is neither animate nor inanimate, but rather it is non-animate. What does this mean? This non-animatedness, Schegk explains, is likened to “a logos and a certain entelecheia of an organic body.”
In this way, Schegk makes a distinction between an animated body and a non-animate principle endowed with, what he calls, a productive potentiality. It is potentiality because it is subordinated to another principal agent, and it is productive because it is active whole remaining in potentiality. But how is it possible? Since for Aristotle, matter is a pure potentiality, and it is pure potentiality because it is inert. Schegk argues that something productive separates from the principal agent and acts as an instrumental agent (hence, not actuality but potentiality) but it itself is not inert since it is endowed with a reason, forming principle (hence, not pure potentiality but productive potentiality). He also equates this productive potentiality with the substantial form of natural things.
Schegk continues to define what this reason-principle means. According to Schegk, Galen recognized that there is some rational in the works of nature, but not wanting to attribute intelligence to all things, Galen gave up an idea of nature as a rational principle. But Schegk tries to find a way to reconcile this apparent dilemma by arguing that there must be a non-intellectual reason-principle in nature, since without such a principle, we cannot explain why nature is regarded as rationally ordered. Here, Schegk is quick to recognize also that the works of nature are different from those of art, because the reason-principles of art are external efficient causes, i.e. artificer, while the reason-principle of nature is internal efficient causes, i.e. the spermatic faculty.
2) How does it do what it does?
The spermatic faculty is conceived as a non-animate instrumental efficient cause, and since only what is animate can produce what is animate, this faculty needs a principal cause to assist it in order to get the generation across. In generation of natural things, the principal efficient cause, i.e. the male parent, exists already in actuality. This agent cannot transmit its own essence to the offspring, because then the offspring would become identical with the parent. What the principal efficient cause does is to transmit the actuality of its existence without sending the essence of itself. And this actuality without the essence is what Schegk calls the second actuality, or the productive actuality. How does it work? What on earth is the second actuality, anyway? Heere, Schegk calls attention to the very useful analogy of perceiving visible things. When we see an apple, for instance, the species/essence of the apple stimulates our vision through its actuality, Schegk tells us, while the species itself remains in its body. So, the apple does not send its essence to us – or else, we will have another apple in our mind in actuality! But its essence only stimulates us, activating our receptivity for the actuality derived from it in our mind. This second actuality is separable from the agent and, Schegk argues, it is our fantasia that makes this reception possible. This second actuality in the seed is what is called the productive actuality, whose ontological status is intermediate between what is animate and what is to be animated, according to Schegk. This is further linked to the psychic and substantial principle, which generates a substance, i.e. the soul.
So, this productive actuality (the second actuality derived from the principal cause) is communicated through this spermatic faculty, i.e. the productive potentiality. Again, it is productive potentiality because it assists the actuality to be communicated to the offspring. And just as the soul of the heaven is corporeal while it is immaterial, this active principle too is corporeal as its principal efficient cause is an animate body in actuality. Like the celestial soul, the productive actuality does not have a substantial matter, hence it is immaterial, but because it animates the body, it must share corporeity with the body it animates. Further, it must be inseparable form a body in order to perform its actions. But the second actuality itself lacks its body as it is only communicated through the body. So, what happens is that when ① the principal efficient cause dispatches in ② the spermatic faculty (i.e. productive potentiality) the second actuality (i.e. productive actuality), ③ the second actuality is tied to and has never left a body, though it gets transmitted from one body to another, for the spermatic faculty is potentiality, i.e. corporeity without materiality, and in this way the spermatic faculty is essential in generation and formation of fetuses since it acts as a vehicle for the second actuality (i.e. the form) to get to the pure potentiality (i.e. the matter). It is in this way that Schegk calls the spermatic/plastic faculty a divine body (corpus divinum).
① The principal efficient cause => ② the second actuality in the instrumental efficient cause => ③ the second actuality gets communicated to the material cause.
This status of having a divine body marks the distinction between the spermatic faculty and the intelligence, which is wholly devoid of matter or corporeity. In sum, this spermatic faculty is different from the celestial element, and this is why Aristotle did not identify this divine body with the celestial element but only said that this divine body is only analogous to the element of the stars. Hence, this spiritual vehicle of the plastic faculty stands between the soul and nature in the ontological hierarchy. Such a spiritual body is called a vital faculty, and is identified as the life-giving heat contained in the seeds and in the residue of animals. It seems that the plastic faculty, spermatic faculty, divine body, spiritual body and vital faculty are all the same thing with different names. This faculty needs a vehicle as its manifestation because the formative energeia, i.e. the second actuality, cannot alone wield its power without an intermediate body.
- Intellect and the Human Soul
In this way, the difference between the intellect and the spermatic faculty has been established – the former is without materiality or corporeity but the latter is without materiality and is corporeal. This leads Schegk to say that the only human soul is separable from matter and all the other souls are generated in the proper sense of the term, that is, drawn from the potentiality of matter by the plastic faculty with the help of its spiritual vehicle which itself is inseparable from matter. So when the soul enters the body in order to animate it, the plastic faculty disappears and is replaced by the soul completely. The plastic faculty as the instrumental efficient cause gets replaced by the former cause proper, i.e. the soul, which remains in the spiritual body. And the human soul, as Schegk tells us, “is not drawn from the potentiality of matter by the plastic logos but is introduced into matter thanks to the intellect’s divine and immortal essence, which may be created but not generated.” So the human soul is consubstantial to this spiritual, divine body, and once the plastic faculty generates the organic body, the soul begins to vivify and the preserve the formed body.
- The principal formal cause and the actuality= the male parent
- The instrumental formal cause = the spermatic faculty, formative power, plastic faculty, divine body, spiritual body
- Productive potentiality, because it assists the actuality to get communicated to the matter
- The second actuality = the movement derived from the male parent
- Productive actuality, because it is without the substantial matter yet but is a pure movement transmitted from the first actuality, i.e. male parent
- Human soul = preexists and is introduced into the fetus once the second actuality is communicated to the matter; it also replaces the spermatic faculty.
- Intellect = celestial element and the human soul; not equivalent with the plastic faculty or the second actuality, which is corporeal without being material.
 Schegk quoted in Hiro Hirai, Medical Humanism, 84-85.
 Schegk quoted in Hiro Hiral, Medical Humanism, 92-93. “This body [the spermatic/plastic faculty] differs from the celestial element because it evidently has no nature separable from its matter nor from seminal liquid. Because of this, Aristotle says that it is not celestial but similar by analogy to the celestial [element], or ‘analogous to the higher element.’ This body penetrates all matter, forming and figuring it, and distinguishes it by the natures of its parts […]. Indeed, this body is totally spiritual and most akin to the substance of the plastic logos. It is established that this [logos] is a certain energeia of the first actuality and, so to speak, the second yet substantial actuality of another animate and physical body. But [the body of the plastic logos] is evidently itself not a physical body. For otherwise, a physical body cannot enter and penetrates its matter because there is no [mutual] penetration of physical bodies.”
 Ibid., 99.
Chapter 2 turns to the French physician Jean Fernel (1497-1558), and his interpretation of Galen in the neo-Platonic flavour. Contrary to Leoniceno via Simplicius, Fernel draws upon Marsilio Ficino to argue for the divinity of the soul. This chapter’s primary aim is to establish Fernel’s position on the status of the soul as essentially divine and argue for the divine presence in natural and medical philosophy. Using the “World-Soul” theory of Ficino, Fernel tried to reconcile Plato with Aristotle via Galen. Hence, it is natural that Fernel holds the view he holds, since his primary source of reference is, as we have seen in the previous chapter, Galen, who held that the soul must be divine, even though Galen himself does not know what that view would entail. So one may see Fernel’s attempt to explain the divinity of the soul as an elaboration of what Galen could have argued for, given his commitment to the divine origin of the soul.
Having argued that the heaven as the fifth element furnishes the composite natural beings with the forms or species, and the eternal circular motion of the heaven is the cause of generation and corruption, he adds that Aristotle held that God the simple and immutable divine substances inside and outside heaven, which in turn sustain the life of all natural beings and enable heaven to rotate on its axis with regularity. So the life on earth depends upon the circular motion of the heavens, but that circular motion in turn depends upon the life on earth, which is sustained by these simple, immutable and divine substances. What are these divine substances? Fernel explains that they are the forms or the seeds according to kinds and species, and the infusion of the forms into matter “activates” life on individual things.
Nothing is more divine in a natural body than the form, which is simple and indestructible. While the matter is a composite of the terrestrial and corruptible elements, the form does is not composed of the mixture of the elements, but rather partakes in the divinity. According to Fernel, the forces of the form are much more powerful than that of the four elements, but at the time, we humans cannot know what they are or how and where they originate because we are limited in our human capacity to know what is hidden by God and made inaccessible to human mind. These hidden things in nature are called occult properties. Since these occult properties exceed the limits of natural philosophy, they are rightly called divine and belong to the realm of divinity. Here, Fernel does something Galen didn’t. While Galen remained agnostic about the nature of the soul and did not explicitly admit the divinity in explaining the realm of natural things, Fernel explicitly introduced the notion of divine force into the natural beings, bringing it down to earth.
Fernel went beyond Galen, and thus expanded on Galen’s conviction that the soul must be divine. In short, Fernel went from “the soul must be divine” to “the soul is of divine nature.” Further, what makes the soul divine is that it pertains to the simple and immutable form that God created and infused upon the natural beings on earth.
God the Creator and Fetal Formation
Fernel advances his own interpretation of Galen that there is supreme intelligence and power in fetal formation and argues for the presence of an architect with a plan as if by theatrical machinery. But this power is not the same as the soul of the fetus, at least not in the sense the Stoics meant by “nature” which lacks any reason-principles. It is rather, according to Galen, some very wise and powerful force, introduced from the outside. Galen held that the efficient and the formative cause of the body is the animal’s congenial heat: a single substance, such as ‘soul’, ‘nature’, ‘native heat’ and ‘implanted temperament’. But Fernel here wants to reject this materialistic conception of the soul as corporeal and destructible substance. For if the soul is simply a congenial heat and a temperament, it is nothing but a mixture of the four elemental qualities, making the soul corruptible and subject to decay. Although Galen usually attributed the causes of natural phenomena to the forces of the temperament and of the elements, he also criticized those who did not recognize a crafting faculty in the body as the formative cause of the body. Drawing upon Galen’s On the Temperaments and On the Usefulness of the Parts of the Body, Fernel concludes that Galen, along with Aristotle, considered the formative cause to be beyond the realm of the four elements. In the passage quoted below, Fernel makes Aristotle, Galen and Plato all agree on the influence of the higher intelligence on the terrestrial sphere. In this way, Fernel concludes that even Galen, who did not discuss about the immediate causes of the formation of living beings, affirmed and argued that there must be the primary cause that is responsible for the formation of living beings. Such ultimate cause must, then, be the divine Creator, and neither his substance nor his way of operation can be grasped by the human mind.
The Divine and Celestial Nature of the Soul
Fernel tackles the problem of what the essence of the soul is by citing Galen. According to On the Doctrine of Hippocrates and Plato, Galen’s view states that the soul is a completely simple, and uniform, incorporeal substance, and is more excellent than the pneuma, which is the soul’s primary instrument for its functions. Upon the departure of the pneuma, the life ceases to function and, on the contrary, life is restored when pneuma returns to the soul. Pneuma is distinguished from the soul in yet another way that the former is corporeal and essentially belongs to the body, whereas the latter is free of body and can subsist by itself. Galen further elucidates the status of the soul in his later work, On My On Opinions, that the soul is neither a property of the bodily substance nor simply an incorporeal substance. It is somewhat half way between being a substance and being a property. What this means is that the soul is both incorporeal and subject to the needs of the body. It needs the body as its house to function, so it is not a substance in a complete sense. It can subsist by itself but it needs the body to function. Fernel agrees with Galen and advances his own argument as to what the consequence of such a reasoning may be. For if the soul is constrained by the bodily boundary, it is not free and independent of body to exercise its functions. If the soul is inextricably attached to the body, it also runs the risk that the soul can be damaged when the host body becomes ill or poisoned. To this, Fernel answers that the soul does not suffer any damage that the body may undergo, despite the fact that it is inextricably attached to the body. What gets damaged is the chain of bonds, or the mode of union, that connects the soul and the body. So if a body suffers poison, then this union gets loosened, as it were, and when the union is broken, the soul flees itself, as if it had been freed from a chain tied to the body. This union or bond is nothing but the innate heat or spiritus, Fernel explains. In this way, the relation of mind to the body is likened to the relation of God to nature, that is, the soul is not linked to the body in such a way that it requires the body’s constant aid, but neither God nor soul is tied down to the body of whose control it has charge. “For in order to think,” Fernel continues, “the soul has no need of the agency of anything to use as an instrument, but by itself and on its own it enters upon reasoning and achieves understanding.”
In short, spirit or the innate heat is what connects the soul and the body, and this mode of union is dissolved, the soul departs the body, and body ceases to be alive.
On the Notion of Faculty and the Formative Force
Fernel explains that by faculty (dunamis) all that Galen meant was the efficient cause of each thing by the term. Faculty is a potency of action and something that the substance of a thing uses as a principle for action. In other words, it is that which designates the active property, which resides in a thing but is different from the thing itself. It is something that emanates from the substance itself.
So the formative force is the same as that which is an efficient cause and the principle of action for the substance, distinct from the substance itself. Because this formative power arises out of the substance from the very beginning, and is distinct from it while sharing intellect, not only the highest part of soul, i.e. rational soul, but also the inferior parts of the soul too must possess some divinity as well. Fernel argues this by citing Galen where he argues that “there should be one soul that both shaped us and the past and makes uses of our individual parts in the present.”
Fernel takes this as Galen making connection between the force which forms the body and the force which governs the body. So, the force which forms the body is formative power that emanates from the substance itself and shares divinity, while the force which governs the body is the tripartite souls of the ancients. Instead of seeing them separately, Fernel argues that Galen advocated one soul to perform both functions. So there is a conflation of the view between the formative power and the souls in Fernel that what molds the body also possess the ability to function each part of the formed body. Because the formative power is divine as has been established, the soul that governs too must be divine as well, being one and the same soul. This all powerful soul is identified with the cosmic mind in Galen, which builds the parts of the human body and embraces all bodily parts without discrimination.
However, such conception of the seed as the substance which gives rise to this celestial mind may be seen to be inconsistent with the earlier claims that 1) if the celestial mind in the seed receives its force form the seed as Galen suggested, this nature cannot produce these forces by itself since it comes after the seed, nor can it be described as celestial or divine since it derives its origin in the earthly matter. Further 2) this view of the seed’s possessing the power to give rise to this formative force may be seen as claiming that the seed which is material is the active principle, rather than a vehicle that carries such power. Fernel responds to the first objection that Galen was here simply speaking commonsensically to make the analogy so we understand in what manner this formative power is in the seed. To the second objection, Fernel is careful to add that the seed is not identical with the formative power, but the celestial mind is placed in the seed.
Recap: The formative force is different from the seed, but the seed is merely a vehicle which carries the divinely arrived formative power. This formative power in turn is identified with the soul that governs the body and the human soul to that extent shares its part in divinity. Further, the formative power needs the body as a house to function well. When the house is damaged, the bond that linked the body and the soul/formative power is broken, resulting in the fleeing of the soul from the body, causing the body death.
The Spiritus and the Innate Heat = On the Union of Mind and Body
Spiritus is more like a body, though it is close to incorporeal beings by virtue of being invisible. It is a means used by any substance devoid of body and hidden to human senses to communicate its force to the body. God too communicates his power through the spiritus and this divine spiritus potentially holds souls and directs them wherever it wishes. Such spiritus is the all-penetrating animus mundi, or the World –Soul, of Plato. So the spiritus is naturally said to be the basis of the soul and its forces, and in it lies the innate heat as well. The nature and the soul’s forces are enclosed in the spiritus and the innate heat. Spiritus and the innate heat, hence, are of divine origin, not sharing in the elementary bodies. The nature residing in the spiritus, then, has a more excellent and divine character than the spiritus itself.
So this “nature” is necessarily God, who uses his spiritus and innate heat to form the living beings. So, when this spiritus and its innate heat are extinguished, having lost its vitality, the life ceases to be. Fernel holds thus that this divine spiritus is that which maintains life in living beings and its extinction causes naturally their death.
What exactly doe she mean by ‘divine’? Fernel answers that it is anything that corresponds and shares with the element of the stars, i.e. the fifth element and aether, and that such element too bestows its own force when the four terrestrial elements merge into the composition of natural beings. Hence, for Fernel, this aether provides the soul’s powers and implants the spiritus in natural beings, determining their form. What is divine is determined by whether the effect of a natural thing exceeds the force of nature or not. So, the composition and mixture of the elements can be the force of nature but the formation of specific organs and heterogeneous parts seems to exceed the capacity attributed to nature. In other words, there needs some other extraneous principle to guide through the formation of fetuses and living beings. Hence, Fernel attributed the cause of concoction to celestial heat, and not merely to the mixture of elements and their moderate heat. Without the celestial aid, concoction is noxious and destructive.
This conclusion has a medical significance, for it supposes a new etiology of diseases, because it is no longer just the imbalance of the four elements/humours that causes the disease, but the elemental heat itself s conceived as something that is potentially bad for the body.
In sum, the living body is seen as a house in which the soul resides, and the spiritus and its innate heat are the instruments of the soul that enables incorporeal power to affect the corporeal body. It is the link or the bond that ties the soul and the body together. Because of this, when this link is broken, the heat is dintiguished and hence the life ceases to be. Such divine spiritus cannot have the terrestrial origin, for then it would be destructible and without reason. The very idea that the formative power is endowed with a rational principle prevents Fernel from concluding that the spiritus is made up of the terrestrial elements. Because it is more divine than the four elements, what controls it, i.e. the world soul, must be more divine than the spiritus it uses. As the spiritus cannot come from the simple mixture of the four elements, it must be implanted into the natural beings at the time of generation, from then onwards directing the fetal formation and taking charge of the nourishment of the body. To this extent, the spiritus of the living body is governed by and closely united with the World Soul.
 Fernel quoted in Hiro Hirai, Medical Humanism, 53-54. “Who could be such a crazy enemy and opponent of the works of nature as not to see at once right at the start, from the skin itself, the skill of the creator? Who will not go on to reflect that some mind or intelligence, endowed with marvelous power, travels through the lands and extends into all parts? For there is nowhere that creatures are not seen to be generated, creatures that all have received some remarkable structure… If some animals are generated in mud, filth, bogs, plants and fruit when they rot – animals that display the marvelous brightness of the being that generates – what should we think [happens] in higher bodies? If the mind and intelligence that reached into such filth is outstanding, how great should its excellence be reckoned in the case of the sun, moon and most of the stars? Certainly, when I brood over this, a mind of no small dimension seems to extend throughout the air surrounding us. If anyone gazes round thoroughly on this with unfettered mind, seeing a mind residing despite it all in such a welter of flesh and humours, seeing too makeup and structure of each living thing (for they all display the evidence and standing of their wise creator), he will admire the greatness and excellence of the mind that is in the heavens.
 Hiro Hirai, Medical Humanism, 61. Fernel quoted, “[w]hen a craftsman is in sound health, yet confined to a house, if he is going to complete any task correctly, he should not just be provided with a suitable tool, but also with a properly lit house, which should not be dark or gloomy; I certainly declare that in the same way the soul, while enmeshed the toils of the body, for the purpose of reasoning and understanding needs a sound state of body, not as an instrument but as a house.”
 Fernel in Hiro Hiral, Medical Humanism, 66-67. “The incorporeal nature confined in the seed receives its powers from this [seed] just as a craftsman receives his [force] from his instrument. But in reality they have arrived divinely.”
[The following is a summary of the book by Hiro Hiral, Medical Humanism and Natural Philosophy (Brill Publishing, December 30th, 2011). Work in progress, and feedbacks are more than welcome.] Chapter 1 discusses about the historiographical survey of the concept of formative power by the humanist physician Leoniceno (1428-1524). Leoniceno’s embryological treatise, On Formative Power (De virtute formativa), includes the analyses of the concept employed by the medical authorities in antiquity onwards, from Aristotle to Averroes, and interprets what was meant by the formative powers. This chapter follows the line of exposition demonstrated in Leoniceno’s book, thereby the focus of this chapter is: reconstruction of Galen’s view on the concept, criticism of Pietro d’Abano for identifying the celestial heat with the formative power by examining Aristotle’s own opinion. Then, Leoniceno gives us his own interpretation on the issue, closing with refuting the account offered by Averroes. Galen, d’Abano and Leoniceno’s Commentary on Them Galen accepts that there must be a supreme intelligence in directing the formation of fetuses, but was uncertain whether or not to equate it with the soul. Traditionally, it was equated with the vegetative soul as it nourishes the fetus, but Galen thought of such vegetative soul to be without intelligence or reason, and hence irrational. Although Leoniceno attributes to Galen the view of Hippocrates that the vegetative soul must be possessed, above all, by the fetuses and it must be that which fashions the body. However, the formation of the fetus and the augmentation, or the nourishing, of the body are two different ideas, for the vegetative soul can nourish the body without intelligence but cannot direct the form of the fetus there is a forming principle. Further, Leoniceno points out the apparent disagreement of Galen with himself in suggesting that the formation of the fetus is attributed to both 1) the vegetative soul and 2) the natural heat, but tries to make sense of these two different ideas by equating them with one another. Leoniceno here appeals to Hippocrates again as the paradigmatic authority of the Greek physicians, and explains that Hippocrates taught the body’s natural heat or the constituent is referred to as body’s temperament, or the mixture of the four elemental qualities. Leoniceno justifies his use of the word temperament to mean the body’s natural heat as the vegetative soul by citing Galen’s own work, On Tremor, in which Galen calls the soul the animal’s natural heat. This heat, then, is neither of external origin as some argued of it as the celestial heat, nor does it come after the animal’s birth, but congenial to it. Here, we see the origin of the Galenic theory of the native or inbred heat. According to Galen, Aristotle wondered if the formative power should be attributed to something more divine. Leoniceno locates the source of such doubt in Meteorology 4.12, where Aristotle attributes the formation of the homogeneous parts to the active qualities of hot and cold, while invoking another cause for the organization of heterogeneous parts. The former is the mutative cause, as it forms organs and alters the shapes for fitting ones, while the latter is the formative cause proper, in that it assumes the supreme art and intelligence of the Creator, who directs the organization of the heterogeneous parts in the human whole. Pietro d’Abano also aligns with Galen and argues that the formative power is of the divine origin and hence active and superior to any other generative power. However, it being immaterial, it cannot act directly on matter, so it needs a certain vehicle that carries it. This subtle body of vehicle is the spirit. In addition, such formative power needs the celestial heat, which is always vivifying and never destructive, as well as the elemental heat, which can vivify and preserve the natural things with the help of celestial heat. Leoniceno, however, disagrees with d’Abano and criticizes him for contradicting Arostotle’s teaching. Although Leoniceno recognizes two kinds of heat involved in the generative process (one is used by nature in generation of animals while the other is used in art for perfection of its own works), he argues that the heat residing in the seed of animals is far from divine or celestial origin. Even though Aristotle himself says that this heat in the seed is analogous to celestial heat, Leoniceno insists that it remains an analogy as Aristotle adds that this vital heat is not fire but the foam-like natural principle in the breath, since as we see no generation happening in solids or liquids under the influence of fire, the heat of the sun which generates is neither fire nor derives its origin from fire. [Q1: But when Aristotle speaks of the vital principle in the generation of animals as analogous to the celestial heat, and it itself is neither fire nor derives its origin from fire, is he not saying that it is not the elementary heat and that it is more like or identical to the celestial heat?] From this textual evidence, Leoniceno argues that this vital heat is enclosed in the seed or the spirit (i.e. breath), and concludes that what is analogous is not identical. In addition to the two heat (one by nature, the other by art), Leoniceno admits a third type of fire, which results from the elemental fire but is more suitable for generating living beings. [Q2: So this vital principle Aristotle speaks of is of elemental fire but is different in its nature?] Leoniceno thus refuses to identify the external celestial heat as the formative power internal to the seed of animals. Leoniceno’s Analyses on Alexander of Aphrodisius and Simplicius Alexander of Aphrodisius likened the vital, formative power in living beings as an irrational mechanism, calling it “nature” and compared its movements to those of marionettes. This is a visualization of Aristotle’s view that the father first introduces the seed a force which moves the matter, along with the form of the father. This first movement activates the second stage of fetal formation, the third activates the fourth and so on. Once the first movement is activated, the rest follows rather indifferent to choice or reason. This is how Alexander qualified “nature” as an irrational power while conceiving it as a determined principle inserted into matter. It is an irrational principle only relative to the reason-principle, producing in a cognizant manner. Simplicius, from whose commentary on Alexander we know much about Alexander’s writings, agrees that nature is like marionettes producing the consistency and exactness, but disagrees with the latter that nature is irrational, even in the relative sense of the term. For Simplicius cannot understand why it is that natural things exist in a way that preserves order and consistency without having any cognition to reach a definite end like the movement of marionettes. It seems rather reasonable to say that nature is not irrational but co-responsible with the immediate causes of things that are generated and corrupted. These immediate causes, in turn, are governed by the celestial bodies according to which beings on this earth are modified. Simplicius, in this way, conceived such formative power as auxiliary to the celestial and intellectual causes. Nature (or formative power) then is the concause with the celestial cause for Simplicius. Leoniceno agrees with Simplicius in conceiving the formative power as auxiliary to the soul, and distinguishes the nature from the soul itself. Leoniceno quotes Simplicius as a conclusion and argues that the seed’s inner nature is the cause for animal generation. Averroes and Themistius Averroes, in like manner, argues that this generative/formative power differs from the other natural powers in animal bodies and that compares such power as belonging to intellectual cause. Since this power acts with the help of the seed’s inner heat, it is obvious that it lies in the seed as a form. For Averroes, this form is distinct from the animal’s innate heat but is comparable to the soul in celestial bodies. Here, we see a divergence from Leoniceno’s, and Simplicius’s, argument that the formative power is not the same as the celestial heat, and Averroes goes back to the identification of the innate heat with the external celestial heat. Leoniceno criticizes him for erroneously drawing upon the conclusion from Themistius and Avicenna’s theory of Giver of Forms, and explains that Themistius’s theory does not demand the existence of a higher agent separated from the body in animal generation, as it would in the case of the Giver of Forms. According to Themistius, Leoniceno wants to argue, the soul residing in the seed is sufficient to form matter. In sum, Leoniceno agrees with Simplicius and refuses to identify the formative power with the external celestial heat, while Pietro d’Abano and Averroes belong to the other camp due to the misunderstanding of the interpretations of Aristotle offered by Themistius and Avicenna. Galen is situated somewhat in the middle ground in that he equates the formative power as not something from external heat nor does it come after the birth, but is congenial to the birth of the animals. Although Galen himself is uncertain of the origin of this formative power, it accords with Leoniceno’s view that it is the animal’s native heat. Galen, however, also argues that this formative power is of a divine origin. To that extent, Leoniceno and Simplicius differ from Galen’s view on what this generative heat really is. Formative Power is… For Galen => of divine origin and shows a sign of intellect; is congenial to the animal’s birth For Pietro & Averroes (via Themistius & Avicenna) => is of divine origin and distinct from the inbred heat. For Leoniceno & Simplicius => is NOT of divine origin and auxiliary to the soul or external heat, but instead is the animal’s power or aptitude in virtue of which lifeless things can be moved an changed.  “All have in semen that which causes it to be productive; I mean what is called vital heat. This is not fire nor any such force, but it is the breath included in the semen and the foam-like, and the natural principle in the breath, being analogous to the element of the stars. Hence whereas fire generates no animal and we do not find any living thing forming in either solids or liquids under the influence of fire, the heat of the sun and that of animals does generate them. Not only is this true of the heat that works through the semen, but whatever other residue of the animal nature there may be, this also has still a vital principle in it. From such considerations it is clear that the heat in animals neither is fire nor derives its origin from fire.” See Aristotle, Generation of Animals, Bk. II, 3. 736b32-737a7.  Simplicius quoted in Leoniceno. “But since bodies are far removed from indivisible and incorporeal nature as well as from the life that subsists in absolute being, and since they are lifeless and do not breathe at all in themselves, too chilled for any kind of life, they have within themselves the last sort of life, which relates that which we call “nature” to power and aptitude. Because of it, even lifeless things can be moved and changed, and it is even said that they are born and act passively on each other.” See, page 38 of this book.