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Medieval Science in Medieval Fiction

This article is based on a chapter that originally appeared in Medieval Science Fiction, edited by Carl Kears and James Paz (King's College London Centre for Late Antique and Medieval Studies, 2016).

We may take as witness an author named Macrobius, who did not take dreams as trifles, for he wrote of the vision that came to King Scipio. (Guillaume de Lorris 1995: 31).

O o appreciate the way that a culture understands the natural world, we need to look at popular works rather than the tomes of intellectuals. So, to help us get to grips with how medieval people viewed the cosmos, this article mines some of the most significant medieval literature for nuggets of scientific wisdom. However, as much of that wisdom ultimate came from classical sources, we must start our exploration in ancient Rome.

Dreaming with Scipio

Shortly before 50 BC, Marcus Tullius Cicero was putting the finishing touches to his exposition of political philosophy, De republica. He consciously modelled his work on Plato’s earlier book of the same name. After expounding on the Roman system of government that was, even then, collapsing around his ears, Cicero concluded with a fable. This also echoed Plato who had ended his own Republic with the Myth of Ur, a story of reincarnation and redemption. Cicero, who lacked Plato’s mystical bent, contented himself with an account of a dream. Although it had a moral message, its author certainly intended it to be read as a work of fiction.

Cicero’s De republica has enjoyed a strange double-legacy. Although much of Cicero’s writing has survived (his work makes up something like a quarter of all extant classical Latin literature), De republica was long thought to have been lost in the early Middle Ages. Then, in the nineteenth century, it was rediscovered in the Vatican Library, lurking behind a work of St Augustine. Centuries earlier, the Cicero manuscript had been cleaned and re-used, such was the exorbitant cost of parchment in those days. The resulting palimpsest has preserved much of De republica into the present day.

In contrast to the whole, Cicero’s conclusion to De republica, Somnium Scipionis (‘The Dream of Scipio’), a parable of republican virtue, was never lost. Instead it became detached from its parent-work and took on a life of its own. In the Somnium, the Elder Scipio, called Africanus for his defeat of Hannibal’s Carthaginian Empire in the Second Punic War, appears to his grandson, the Younger Scipio. Scipio Junior is about to carry on the family tradition by razing Carthage to the ground. The grandfather takes the grandson on a tour of the universe to impart some unsubtle messages about the insignificance of the individual. Despite Cicero’s explicitly moral message, the Somnium found its niche as a neo-Platonic cosmography textbook. This was not science fiction, but fiction as science. Cicero was careful to place his vision within the confines of the best science of his day. He did not intend it, but his narrative provides a framework on which an explanation on the constitution of the universe can be hung.

The man who took on the task of providing the scientific commentary to Somnium Scipionis was Macrobius. He lived four centuries after Cicero but, other than that, we don’t know much about him. He was probably a pagan from the province of Africa, roughly modern Tunisia (Macrobius 1952: 4). He certainly doesn’t show much interest in the surging success of Christianity. That did not stop his commentary on the Somnium Scipionis becoming a massive success. After the collapse of the Western Roman Empire, it helped to teach Europe knowledge of the Greek science that would otherwise have been lost. The Carolingians were especially keen students of the work and ten manuscripts still survive from the ninth century.

Macrobius maintained his fame throughout the Middle Ages. As late as the fourteenth century, Geoffrey Chaucer was dropping his name all over the place. There is a nod towards him in the Nun’s Priest’s Tale. And Chaucer begins the Parliament of Fowls with a summary of the Somnium Scipio:

Thow hast the so wel born
In lokynge of myn olde bok totorn
Of which Macrobye roughte nat a lyte
That sumdel of thy labour wolde I quyte. (ll. 109-112) 1

As I mentioned above, in this article, we won’t be spending much time at the universities and other places of learning. Instead, we will examine how the medieval universe was reflected in the literature and popular writing of the period. All fiction is set within a world governed by physical laws. Most authors assume his or her readers share their worldview. When they do not, confusion can result. The fact he was so widely read makes Macrobius the perfect guide.

In delineating the medieval universe, we should not aim for precision. Modern scholars can differentiate between the cosmological visions of Plato and Aristotle. They know that the philosophers’ model of the heavens is not at all like that of a mathematician like Ptolemy. Medieval authors did not concern themselves with such subtleties. They were not in the least bit concerned that Macrobius was a Platonist and other writers, like Boethius, more inclined to Aristotle. Some authors, like Chaucer and Dante, were intimately familiar with the ancient sources on the workings of the world. Chaucer wrote a treatise on how to use an astronomical instrument, the astrolabe, while Dante’s epic Divine Comedy is set in an amalgam of the Greek and the Christian cosmos. However, these influences will not necessarily be consistent and it is pointless trying to exactly identify them. Even authors who tell us about their sources are not always accurate.

In the Middle Ages, natural philosophy was considered a subject worthy of study. It should not need repeating that there was no animosity towards the topic emanating from the Church. As Boccaccio said in The Decameron, a basic knowledge of science was necessary ‘to gain some understanding of the first principles of things, as a gentleman should’ (Boccaccio 2008: 468). He adds that this was socially acceptable, as long as one didn’t try to make any money from it. Indeed, all of book seven of John Gower’s Confessio Amantis is taken up with a summary of the science and wisdom that Aristotle supposedly taught Alexander the Great. The only trouble is, in Gower’s hands, Aristotle ends up sounding like a dyed-in-the-wool Platonist.

Mathematics or the Quadrivium

The basic structure of education in the Middle Ages was inherited from late antiquity. Martianus Capella’s The Marriage of Philology to Mercury, dating from the sixth century, laid out the framework in an allegorical form. There were seven liberal arts, so-called because they were subjects worthy of a free man’s attention. In The Marriage, each liberal art is represented by a nymph who, suitably attired, entertains the wedding guests by regaling them on her subject. Four branches of mathematics (the quadrivium) were represented among the seven liberal arts. The other three (the trivium from which we get the word trivial) were grammar, rhetoric and logic. The quadrivium, consisting of arithmetic, music, geometry and astronomy, were traditionally the ‘arts’ that university students had to master in order to earn their MA degree. Their status as intellectual rather than practical pursuits is indicated by the way that they were embroidered into a robe that Chrétien de Troyes tells us that King Arthur awarded to the knight Erec (Chrétien 1992: 245). In the courtly world of the troubadours, even monarchs and the nobility could enhance their reputations by demonstrating some knowledge of mathematics. Chrétien cites Macrobius as his source for these subjects but Martianus Capella is a much more likely origin.

The liberal art of arithmetic was akin to modern number theory rather than the practical skills of adding, multiplying and other kinds of ready-reckoning. A student was supposed to master the properties of numbers in order to train his mind to deal with abstract Platonic principles. The standard textbook had been produced by Boethius in the sixth century as a philosophical prolegomena. Likewise, learning music did not involve playing an instrument or singing. With Boethius the guide again, students studied harmonics and ratios. Geometry was based on the first few books of Euclid’s Elementa. Boethius produced his own summary (now lost) and the Elementa itself was translated into Latin in the twelfth century. The logical sequence of Euclid’s great work, from the most basic axioms to progressively more complicated theorems, all deductively proven, continued the pattern of arithmetic and music. Geometry did have practical applications, but this was not the reason that students were taught it. Astronomy was a branch of mathematics because it was concerned with predicting the movements of the planets across the sky, not with explaining the constitution of the heavens. Questions about why the planets moved or what they were made of were within the purview of philosophy, not mathematics. That said, astronomy owed its place in the quadrivium to its ability to raise the sights of students upwards towards the perfect realms beyond the moon.

When students had finished their studies of the quadrivium, they moved on to the three philosophies: ethics, natural philosophy and metaphysics. Natural philosophy was the closest equivalent to what we think of as science. Thomas Usk closely associated natural philosophy to the quadrivium, much as we would probably do today. In The Testament of Love, he wrote:

The first spece of philosophie is naturel; whiche in kyndely thynges treten, and sheweth causes of heven, and strength of kyndely course; as by arsmetrike, geometry, musyke, and by astronomye techeth wayes and course of hevens, of planetes, and of sterres aboute heven and erthe, and other elementes. (Usk 2002: 127)

Metaphysics had some overlap with natural philosophy and, together, all these subjects were just steps on a journey towards the divine. Students might eventually complete this quest if they carried on with their studies all the way to qualification as a theologian. But these sorts of advanced studies need not detain us here. Instead, we should return to earth and see how medieval authors saw the world they lived in.

On and under the Earth

Hell was a real enough place to many medieval people. Pagan mythology had placed Hades underground with entrances in areas of high volcanic or geothermal activity. Combined with the Jewish vision of Gehenna, or the furnace, hell as a place of fire and torment has been a constant from the earliest era of Christian thought. In the eighth century, the Venerable Bede described a vision of hell as ‘very broad and deep valley of infinite length’ and a fiery chasm (Bede 1990: 285).

For Macrobius, the cosmic hierarchy was physical. The centre of the universe was also its depths: a region of change and decay. The very middle of the world was the logical location for hell, not least because it was the point furthest away from the highest heavens. The perfection of the stars and planets was demonstrated by their characteristics of circular and unvarying motion. The situation below the orbit of the moon was the opposite: things naturally moved in straight lines rather than circles. The Earth was a seething mass of generation and corruption. Later, in the fourteenth century, Dante combined Macrobius’s scientific vision with the Christian religious tradition to reconstruct hell as a series of concentric circles running deeper and deeper underground. The epicentre of depravity was at the centre of the Earth, the location of the dustbin of the universe. It is here that Dante places Lucifer. Macrobius allegorises the punishments of the damned from pagan mythology. While Dante is in no doubt about the reality of hell, it’s hard to escape the feeling that he is doing the same kind of thing.

All of terrestrial matter was thought to be made up of the four elements: earth, water, air and fire, and each element had its own properties. Aristotle had proposed absolute directions of up and down, being away from and towards the centre of the universe. In his commentary on the Somnium Scipionis, Macrobius suggested that weight was the most basic property of the elements (Macrobius 1952: 106). To move downwards was in the nature of heavy things. The element earth was the heaviest and therefore it moved naturally towards the centre of the universe. Water rested on the earth and air floated above it. The most rarefied element was fire. Its natural place was above the air and some medieval scholars postulated that there was an invisible ring of fire that formed the boundary between the terrestrial and celestial realms. Other properties were also associated with each element. Earth, for instance, was cold and dry; air was hot and wet; fire was hot and dry. Substances took on these properties from the balance of the elements of which they were formed. None of the elements were fixed. They could merge into one another, producing a cycle of decay and regeneration. Change was in the nature of the terrestrial realm and even the elements could transform into each other. Exploiting this was the goal of alchemy.

Much alchemical literature originated in the Arab world and Christian authors continued the tradition by attributing their own works to famous Muslim predecessors. The lore of alchemy was an amalgam from many sources, but the basic theory suggested that all metals had the same base, being mercury, which could be given specific properties by a tincture, usually associated with sulphur. Applying the correct tincture in the presence of the philosophers’ stone could yield a more valuable metal, preferably gold. In a bull called Spondent partier issued in 1317, Pope John XXII, who knew a thing or two about alchemy and even had an instruction manual attributed to him, denied such transmutation was actually possible. He noted that, under an Aristotelian schema, materials possessed an underlying substance which did not change even when the visible accidents did. Thus, while an alchemist might give his manufacture the appearance of gold, it would not be the real thing. Passing it off as such was fraud (Hannam 2009: 132). Dante confined alchemists to the eighth circle of hell, as we see in Inferno: ‘For alchemy,’ one lamented, ‘which I practiced in the world, Minos damned me, who may not err’ (Dante 1996: 457 [29:118]). In any case, alchemists were notorious for losing money rather than coining it. Chaucer satirised them in The Canterbury Tales. In his Canon’s Yeoman’s Tale, a smorgasbord of alchemical lore, the teller despairs of

This cursed craft whoso wole exercise
He shal no good han that hym may suffise
For al the good he spendeth theraboute
He lese shal; therof have I no doute. (VIII: 830-33)

The conflicting metaphysical systems of substance and accident, the four elements and alchemical tinctures meant that the medieval world did not have an agreed theory of matter. There were even some atomists who had found the idea in Plato’s Timaeus and kept it alive despite Church disapproval. Medieval authors could pick and choose, farming each system for metaphors as they required.

In contrast, the shape of the Earth was not a controversial question in the Middle Ages. Medieval scholars knew it was a sphere and there were plenty of ways to prove this, not least the way ships disappear under the horizon. Even in the early Middle Ages, all the sources agreed the Earth was round. Macrobius was clear on the matter and even gave an accurate enough figure for the Earth’s size (Macrobius 1952: 172). This meant that medieval people were perfectly aware that the part of the Earth that they inhabited was just a small fraction of the whole.

Looking for evidence of a flat earth has led some modern writers down a blind alley. For instance, the sixth-century encyclopaedist Isidore of Seville described the world as a wheel. That sounds pretty flat. But Isidore had in mind the model of the Earth described by Macrobius and others, including the first-century Roman writer Pliny the Elder. Pliny’s massive Naturalis Historia, written in the first century AD, was a collection of ancient Greek natural lore that the Roman author had arranged as best he could. Macrobius and Pliny divided the Earth up into five climatic zones. To the north was a region of bitter cold. This frozen wilderness was uninhabitable. Our own temperate region was banded on the other side by the equatorial torrid zone. Extreme heat meant that it too was uninhabitable by human beings (Macrobius 1952: 202). When Isidore said the world was shaped like a wheel, he meant the clement slice of the globe between the hot and cold extremes. We inhabit the edge of the wheel, not its face.

According to Macrobius, the torrid zone was ‘scorched by an incessant blast of heat’, a wall of fire that prevented any kind of intercourse between the northern and southern hemispheres (Macrobius 1952: 202). This clearly raised some issues of its own. The most pressing was the question of whether or not the antipodes were inhabited. Given there was no way that Adam’s descendants could have made their way there from the Garden of Eden, it seemed unlikely. A troubling corollary was how Christians were supposed to preach the Gospel to any aboriginal Australians who did exist. A dispute on this matter between eighth-century German missionaries went all the way to the Pope who ruled definitively that there were no Australians. Still, the argument on the antipodes didn’t prevent both missionaries from eventually being canonised (Hannam 2009: 37).

The ancient and medieval eras knew only of Europe, Asia and Africa. It was relatively easy to map all three onto a flat sheet of parchment without needing to worry about spherical projections. This gave rise to the genre of mappa mundi (and incidentally another misconstrued piece of evidence for belief in a flat earth). Jerusalem appeared as the centre of the world on these maps, both literally and allegorically, with ocean surrounding the three continents. But rumours of western lands beyond the sea persisted throughout the Middle Ages. In the sixth century, the Irish monk St Brendan and a group of followers took a coracle out into the Atlantic on a voyage of discovery. The version of ‘Brendan: The Legendary Journeys’ we have today dates from centuries after his death and is clearly a work of pious fiction. The saint and his crew enjoy various salutary adventures before they are allowed to reach the Isle of the Blessed (Farmer 1988: 266). This earthly paradise, concealed behind a bank of darkness, consequently found itself included on maps for many centuries. It was originally located roughly in place of the Canary Islands (obviously the good weather reported in Brendan’s legend meant the Isle was well to the south of Ireland). But as explorers opened up the Atlantic Ocean in the later Middle Ages, Brendan’s land was pushed further to the west until it disappeared altogether in the sixteenth century.

Accounts of fictional journeys were extremely popular in the Middle Ages. The Travels of Sir John Mandeville, an Anglo-French narrative from the fourteenth century, was the most celebrated of the lot. Columbus took a copy with him when he voyaged west seeking the Spice Islands. Sir John is probably a nom de plume and it is possible that whoever wrote The Travels never ventured much further than his local library. But the book does reflect an authentic medieval view of the world rather than simply the imagination of the author. To prove the Earth is a sphere, the author spins a yarn about an explorer who almost achieved history’s first circumnavigation. ‘If he had gone a bit further,’ explained Sir John Mandeville, ‘he would have reached his own district. But […] he could not get transport any further, so he turned back the way he had come: thus he had a long journey!’ (Mandeville 1983: 129).

Flora and fauna

Sir John Mandeville’s Travels also present us with the fantastic fauna of the world. He described grotesque creatures, like the crocodile, and men with no heads whose faces were in the centre of their chests, and dog-headed people called Cynocephales. But he did not invent any of these things. They had a long pedigree, via Pliny the Elder, going all the way back to classical Greece. When it came to the Cynocephales, the liveliest debate was about whether they could be converted to Christianity and consequently saved. According to the ninth-century bishop Ratramnus, the crucial point wasn’t what they looked like, but whether they could reason (Bartlett 2008: 98). That was the distinguishing mark of Adam’s descendants and what was meant by being formed in God’s image.

The rest of the natural world also bore the mark of God. Bestiaries attempted to make sense of the divine messages imprinted into the appearance and behaviour of animals. The bestiary was an illustrated encyclopaedia of creatures originally compiled around the third century AD in Syria or Egypt. It was translated into Latin soon afterwards. Various expansions and redactions continued to be produced into the sixteenth century. It’s easy for us to see bestiaries as works of fantasy. Their content came from a wide variety of sources, among which observation from nature is conspicuous by its absence. Not all the animals that the bestiaries describe even existed and the behaviour of those who do is obviously fantastical. For example, we learn how the beaver will bite off its own testicles (which were believed to be valuable medicinally) to leave them as a lure for the hunter in pursuit (Clark 2006: 130). The pelican allegedly slays its chicks by pecking them to death, but after three days showers them with its blood and revives them (Clark 2006: 177). And everyone knows how the phoenix immolated itself before being reborn from the ashes.

The Christians who first assembled this material added an allegorical gloss to their work. The behaviour or appearance of each animal imparted a religious lesson. The beaver cast away the offending part of its anatomy to avoid the hunter just as we should throw away our sins to escape the devil. It is a clear parallel to Jesus’ order to cast out our eye if it makes us stumble (Mark 9: 47). The rebirth of the phoenix and of the pelican’s chicks provided analogies to the death and resurrection of Jesus. Thus the bestiary was not so much a spotter’s guide to the natural world, but more of a moral textbook. The classically sourced knowledge of nature was largely taken for granted, but it was reinterpreted through a Christian lens.

To medieval Christian writers, the world was God’s creation and that gave rise to certain inevitable corollaries. These were perhaps best expressed in the twelfth century by the theologian Thierry of Chartres:

Because the things in the world are mutable and corruptible, it is necessary that they should have an author. Because they are arranged in a rational way and in a very beautiful order, it is necessary that they should have been created in accordance with wisdom. But, because the Creator, rationally speaking, is in need of nothing, having perfection and sufficiency in himself, it is necessary that he should create what he does create only through benevolence and love. (Hannam 2009: 113)

Signs of God’s creative activity were everywhere. Animals, as described in bestiaries, existed to impart theological lessons to mankind. As Hugh of St Victor, another twelfth century theologian, had said, ‘the whole of the sensible world is like a kind of book written by the finger of God’. We should be able to read the book of nature to interpret its religious messages. The obsessive medieval search for meaning in the natural world was based on the belief that everything had a purpose. Nature did nothing in vain. Again, this idea was classical and clearly expressed in the teleological philosophy of Aristotle. But it easily translated into a Christian worldview where God the creator didn’t do things for fickle reasons. This gave the world a very different texture from that perceived by us moderns. Modern science teaches us that the universe just is. It has no purpose and requires no explanation, except perhaps from deeper levels of its own existence. We are simply the products of random chance, one of a countless number of possible beings. The universe doesn’t teach us anything except about itself. Even our much vaunted rationality is only an evolutionary side product of our need to be social animals and justify our places in the tribe. To medieval eyes, a purposeless universe, one that lacked a reason, would itself be irrational. A teleological world is one where causes have effects all the way back to the final cause: God himself.

Plants and herbs also showed evidence of the benevolence of God. The great herbal of Dioscorides, written in the second century AD, provided remedies for all sorts of ills. However, folk healers could determine the correct herb to use for a cure by more empirical means than looking them up in a book. The right treatment, they believed, could be recognised from the signature of the plant in question. A herb’s physical properties were expected to reflect its therapeutic value. For example, the thick spongy leaves of the liverwort seemed to resemble that very organ. Its appearance was a hint that God had given to man on where to look for a cure for liver problems. Likewise, the walnut’s hard outer casing enclosing twin hemispheres looked like the skull enclosing the brain. What better way to treat an illness of the head? (Hannam 2009: 113).

Medieval medicine

The theory on which a medieval physician based his work had been inherited from the ancient Greeks, primarily the work of Galen mediated through Arabic writers in the interim. Human bodies, the theory ran, contained four humours: blood, phlegm, yellow bile and black bile. Each of us has a unique balance of these humours when we are healthy. We must ensure that the optimum proportions are maintained through diet, lifestyle and preventive treatment. That said, in most people, one of the humours predominates and determines the kind of person they are: sanguine, phlegmatic, choleric (from the Greek for bile) or melancholy (from the Greek for black bile). The latter form of bile was held responsible for putrefaction and was generally felt to be the worst of the humours. As John Gower wrote in book 7 of Confessio Amantis:

Of therthe, which is cold and drye
The kinde of man malencolie
Is cleped, and that is the ferste
The most ungoodlich and the werste. (Gower 1901: vol. 3, 244, lines 401-4)

Nonetheless, like salt, black bile was still essential to the good working of the body in moderation. When the humours get out of kilter, we get ill. Luckily, the symptoms of our malady could help a doctor diagnose which of the humours was in excess and prescribe remedial treatment. For instance, if you were sweating and running a temperature, that suggested a surfeit of blood. Blood, it was believed, was constituted in large part from air and so, like air, had the properties of being hot and wet. Likewise, as Gower alludes in the quotation above, black bile was earthy and so cold and dry. A patient suffering from an excess of blood presented the characteristics of moistness and heat through his or her feverish sweating. The solution, naturally enough, was to drain off the glut of blood to restore balance to the humours. Since a fever is symptomatic of a great number of diseases, bleeding was a treatment that was applicable to a vast number of cases. In other situations, doctors might prescribe a regime of exercise, rest or diet. For instance, Boccaccio tells a tale in book 10 of The Decameron about an Abbot of Cluny, afflicted by stomach trouble, being directed to the baths of Siena to certainly be cured (Boccaccio 2008: 563).

It goes without saying that medieval doctors were, despite great erudition and professional prestige, singularly ineffective. Boccaccio, writing The Decameron in the shadow of the plague, was acutely aware of this and so more critical of doctors than most writers. In book 6, he noted physicians from the great school in Bologna ‘wearing long flowing robes of scarlet trimmed with ermine’ and ‘how little their ability lived up to this display’ (Boccaccio 2008: 491). But medicine was also the branch of science that most commonly touched everyday life, so it received a great deal of attention from authors of fiction.

The Doctor of Physic in Geoffrey Chaucer’s The Canterbury Tales used a combination of natural magic, probably derived from traditional herb lore, and Greek medical theory based on Galen. Chaucer writes, when he introduces the good doctor in the General Prologue:

In al this world ne was ther noon hym lik,
To speke of phisik and of surgerye,
For he was grounded in astronomye.
He kepte his pacient a ful greet deel
In houres by his magyk natureel.
He knew the cause of everich maladye
Were it of hoot, or coold, or moyste, or drye.
And where they engendred, and of what humour. (I: 412-421).

In the third line quoted above, Chaucer notes something else about medieval doctors that we might not expect. They relied a great deal on judicial astrology in the course of their work. Doctors would consult their patients’ horoscopes to determine the optimal time for bleeding and other treatments (although the bleeding itself would be carried out by a barber surgeon because a learned doctor couldn’t be expected to indulge in such manual work). This meant that astronomy and astrology were central parts of the syllabus at medical schools like Bologna and Padua. The famous thirteenth-century physician Bernard Gordon, who is name-checked by Chaucer, admitted that he once had got the time of a bleeding wrong without any ill effect to his patient. But even he still advised sticking to the theory (Hannam 2009: 119).

Astrology, as with most other ideas about nature, went back to the ancient Greeks. It was widely understood in the Middle Ages that the universe was a homogenous whole such that the heavens and earth were linked in ways that were subtle but real. For instance, the twelve houses of the zodiac each had a series of correspondences in the sublunary world. The organs of the body and the various curative plants were associated with particular stars, as was each human being through their horoscope. The planets, which included the sun and the moon, also influenced events on Earth. Today we think of a horoscope as being determined by the single sign of our birth. But this is only the house in which the sun was present on that day. We also each have a moon sign, a Mars sign and signs for all the other planets, as noted by Macrobius in his commentary on the Somnium Scipionis (1952: 175). Thus a complete horoscope is a much more complicated business than assigning humanity to the twelve signs of the zodiac. The influence of the planets was generally felt to be greater than that of the fixed stars, not least because the planets were closer and the sun so obviously affected the Earth. So, just as one of the four humours could predominate and determine ones temper, so people were often associated with planets. Again, the descriptive adjectives survive to this day: mercurial, venereal, martial, jovial and saturnine. In Paradiso, Dante organises paradise around the orbits of the seven planets, with the souls of the blessed congregating around their respective spheres.

Not everyone approved of astrology. Dante condemned celebrity astrologers like Michael Scot and Guido Bonatti to hell for divining with the aid of demons. They were cursed to spend eternity with their heads twisted around backwards as punishment for seeking too earnestly to look forward into the future (Dante 1996: 311 [20:116]).

Into the Stars

Astronomy had few practical applications besides its importance to astrology. But the constitution of the heavens was a matter of enormous philosophical interest. It was one of the main topics discussed by Macrobius in his commentary on the Somnium Scipionis. Cicero himself makes the point that the universe is very, very large. The enormous size of the cosmos was a moral as well as a scientific issue. At one point, Scipio looks down upon the Earth from far above and notes how small and inconspicuous it is in the vastness of the heavens. The conquests of Rome, that had seemed so magnificent on Earth, were revealed as quite puny from this vantage point. Boethius noted the same thing in The Consolation of Philosophy: the Earth is but a point compared to the vast vault of the heavens (Boethius 1999: 41). The South English Legendary, an English collection of saint’s lives, has a novel way of illustrating the vast size of the universe:

Muche is bitwene hevene & earthe: for the man that migte go
Everich dai forti mile evene uprigt and eke mo
He ne ssolde to the heiost hevene: that ye aldai iseoth
Come in eigte thousond yer. (D’Evelyn 1956: 418; see further Lewis 1994: 98)

Forty miles a day for eight thousand years comes to about 120 million miles, which is of the same order of magnitude as the determinations of some ancient Greek astronomers, but its use in a vernacular poetry collection like the Legendary shows this was common enough knowledge. That said, the distance really meant ‘further than you can imagine’ much like the billions of light years we hear about in both science fact and science fiction today.

For Macrobius, the closest of the seven planets was the moon. Its orbit marked the boundary between the atmosphere and the heavens, which consisted of the mysterious fifth element of ether (1952: 182). Elsewhere, John Gower explained the fifth element in his Confessio Amantis:

That yit ther is an element
Above the foure, and is the fifte
Set of the hihe Goddes yifte
The which that orbis cleped is. (Gower 1901: vol 3, 246, lines 610-13)

As we saw above, the sublunary world was one of change and decay whereas the heavens rolled ever onwards in unvarying cycles. The cycles of the planets gave rise to a harmony Platonists called the Music of the Spheres and which mankind could enjoy vicariously through contemplation (Macrobius 1952: 186). This meant that, where change did occur among the stars, medieval observers either assumed that it was an atmospheric phenomenon (such as a comet) or they did not really register it at all (such as the supernovae of the eleventh century).

Aristotle claimed to have proved that the universe must be a sphere bounded by the fixed stars. Between the fixed stars and the moon was the realm of ether containing the wandering stars, or planets. Natural philosophers imagined the planets were mounted on the rim of great spheres that turned through the sky with a uniform circular motion. Unfortunately, the planets themselves moved in ways that did not appear to be uniform or circular. Their speed varied and sometimes they even went backwards. This deviancy had been explained by Greek mathematicians, culminating with Ptolemy in the second century AD. His model of epicycles, eccentrics and equant points combined several uniform circular motions into an irregular path that closely matched the observed track of the planets. These complications meant that calculating the position of the planets, a matter of great importance to astrologers if no one else, was a challenge. Consequently, most astrologers used special tables for their prognostications and thereby avoided the tricky mathematics. As for the philosophers, they tended to ignore the implications of Ptolemy’s scheme, specifically that the heavens might not be constituted in the elegant way they imagined.

Beyond the planets was the sphere of the fixed stars. This was also turning, with a complete revolution once every twenty-four hours. For Macrobius (1952: 156), it carried the entire universe with it. Some medieval scholars, specifically in fourteenth-century Paris, asked if perhaps it might be the Earth that was rotating each day. They concluded that you really couldn’t tell since there is no reason that we should feel the Earth move. Nonetheless, the idea still seemed implausible. The Earth simply did not appear to be moving. Unsurprisingly, then, medieval authors adopted the common-sense conclusion that the Earth was fixed and immobile at the centre of the universe.

Cicero closes the Somnium Scipionis with the older and younger Scipios at the outer edge of the material universe discussing the first mover. This eternal entity was postulated by Aristotle as a kind of deity which kept the celestial spheres in motion, thus providing the whole cosmos with energy. For Christians, the first mover was identified with God whose love made the world go round. The highest heaven was beyond the sphere of the fixed stars. Granted, Dante populated the planetary spheres with the souls of the blessed, but this was just their temporary lodging before the end of the world and their transportation to the eternal beatific vision beyond.

Judgement day was a certainty. Just as the universe had a beginning, it must also have an end. The sweep of cosmic history was accomplished in a single day by the mystery plays of England, performed on the feast of Corpus Christi, most famously in York. There were approximately fifty plays in all, portraying the lifecycle of the world as a coherent whole. Plays that covered events in the Old Testament were explicitly structured to look ahead to the life of Jesus. But the bulk of the plays dealt with material from the Four Gospels, enlivened by later legendary accretions. The cycle has its climax in the last judgement and the end of the world. As Christ explains,

This woeful world is brought to end,
My Father of heaven he will it be;
Therefore to earth now will I wend
Myself to sit in majesty. (Beadle 1999: 273)

Thus, the medieval universe was purposeful, coherent and pregnant with meaning. The Platonic vision of Cicero suited a Christian universe, with a few amendments here and there. It made religious and philosophical sense (Lewis 1994). For the authors of the imaginative literature of the Middle Ages, it also provided a stage upon which they could tell their stories. For modern readers trying to understand the Middle Ages, this combination of the sacred and profane, where the world obeys natural laws but is suffused with the divine, can be the most difficult aspect to master.

Works Cited

Bartlett, Robert. 2008. The Natural and the Supernatural in the Middle Ages (Cambridge: Cambridge University Press)

Beadle, Richard, and Pamela King (eds). 1999. York Mystery Plays: A Selection in Modern Spelling (Oxford: Oxford University Press)

Bede. 1990. Ecclesiastical History of the English People, ed. D.H. Farmer (Harmondsworth: Penguin)

Benson, Larry D. (ed). 1987. The Riverside Chaucer. 3rd edn. (Boston: Houghton Mifflin)

Boccaccio, Giovanni. 2008. Decameron, ed. and trans. J.G. Nichols (Oxford: Oneworld)

Boethius. 1999. The Consolation of Philosophy, ed. and trans. Victor Watts (Harmondsworth: Penguin)

Chrétien, de Troyes. 1992. Erec and Enide, trans. Dorothy Gilbert (Berkeley: University of California Press)

Clark, Willene B. 2006. A Medieval Book of Beasts: the Second-Family Bestiary: Commentary, Art, Text and Translation (Woodbridge: Boydell Press)

Dante Alighieri. 1996. The Divine Comedy of Dante Alighieri, ed. and trans. Robert Durling. 3 vols (Oxford: Oxford University Press)

D'Evelyn, Charlotte, and Anna J. Mill (eds). 1956. The South English Legendary. 3 vols (Oxford: Oxford University Press)

Dioscorides. 2000. De Materia Medica: Being an Herbal with many other Medicinal Materials, ed. and trans. T.A. Osbaldeston and R.P.A. Wood (Johannesburg: IBIDIS)

Farmer, D.H. (ed.). 1988. The Age of Bede (Harmondsworth: Penguin)

Gower, John. 1901. The Complete Works of John Gower, ed. G.C. Macaulay. 4 vols (Oxford: Clarendon Press)

Guillaume de Lorris and Jean de Meun. 1995. The Romance of the Rose, trans. Charles Dahlberg (Princeton: Princeton University Press)

Hannam, James. 2009. God’s Philosophers: How the Medieval World Laid the Foundations of Modern Science (London: Icon)

Lewis, C. S. 1994. The Discarded Image (Cambridge: Cambridge University Press)

Macrobius. 1952. Commentary on the Dream of Scipio, trans. William Harris Stahl (New York: Columbia University Press)

Mandeville, John. 1983. The Travels of Sir John Mandeville, trans. C.W.R.D. Moseley (Harmondsworth: Penguin)

Martianus Capella. 1977. The Marriage of Philology and Mercury, ed. and trans. William Harris Stahl and Richard Johnson (New York: Columbia University Press)

Usk, Thomas. 2002. The Testament of Love, ed. Gary W. Shawver (Toronto: University of Toronto Press)

  1. All quotations from the works of Chaucer are from Benson (1987). ↩︎

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© James Hannam 2017