Astrology, the Flu, and Free Will

One highly influential form of divination in the ancient world, which also had a major impact on the casting of spells and creation of charms, was astrology. The ancients, whether Egyptian, Babylonian, Persian, Greek, or Roman, all paid close attention to the sun, the moon, and the five visible planets. They regarded this seven “wandering stars” in particular as divine entities whose movements had a powerful effect on earthly creatures. To a very great extent, Medieval European Christians inherited this perspective.

To many people today, especially those who have had enough of nonsensical Facebook posts about zodiac signs and personality types, the idea that the planets can affect our lives seems ridiculous. As Bailey points out, however, it is actually quite intuitive:

“That astral bodies imparted energies that could influence terrestrial ones was hardly an outlandish idea—one had only to note how the moon influenced tides or more basically how the rising sun warmed the air to be convinced of this fact. That the planet Mars could impart martial energies or that the power of Venus somehow facilitated amorous attraction or sexual fertility was widely accepted in the Middle Ages, and much more serious intellectual effort was spent working out exactly how these various forces operated. Although learned astrologers sometimes made predictions about the future, they would hardly have considered themselves diviners or magicians. Rather, they would have presented themselves as wise men and philosophers exploring the forces of nature.”[1]

In addition to tidal forces and solar heat, I would also add that skeptics should ask a nurse about working during a full moon.

As Medievals tangled with the precise workings of the influence of the stars on earthly life, they were quick to note that this influence was not direct. Lewis in The Discarded Image has an excellent passage on this:

“In accordance with the principle of devolution or mediation the influences do not work upon us directly, but by first modifying the air. As Donne says in The Exstasie, ‘On man heaven’s influence works not so But first it imprints the air.’ A pestilence is caused originally by malefical conjunctions of planets, as when

Kinde herde tho Conscience and cam out of the planetes And sente forth his forayers, fevers and fluxes.

(Piers Plowman, C. XXIII, 80.)

But the bad influence operates by being literally ‘in the air.’ Hence when a medieval doctor could give no more particular cause for the patient’s condition he attributed it to ‘this influence which is at present in the air.’ If he were an Italian doctor he would doubtless say questa influenza. The profession has retained this useful word ever since.”[2]

That’s right. When you say you have the flu, you’re actually taking part in an old tradition of ascribing airborne maladies to the influence of the planets. You astrologer, you.


So how did we get here? Clearly the Church no longer regards astrology as kosher. How did this happen?

The answer is partly that the Church always had certain objections to astrology, or at least to the abuse of it. Lewis outlines three of these objection:

“(1) Against the lucrative, and politically undesirable, practice of astrologically grounded predictions.

(2) Against astrological determinism…

(3) Against practices that might seem to imply or encourage the worship of planets—they had, after all, been the hardiest of all the Pagan gods.”[3]

Of these three objections, it was the second that caused the most debate among Medieval philosophers and theologians. Lewis devotes more room to this problem than either of the others, and Bailey concurs in regarding it as a highly problematic issue:

“The difficulty lay in rescuing some acceptable systems of astrology from the condemnations of earlier authorities, and from the dilemma that the determinative power of astrological forces seemed to conflict with the important Christian notion of human free will.”[4]

Christianity presents a notion of human responsibility, and an emphasis on moral decision-making, that seems reliant on some notion of free will. After all, if King David was compelled to sin with Bathsheba due to the lascivious influences of Venus, how can he be held accountable for his actions? How can Abraham be praised for his faithfulness when it was merely the stars that decreed his actions?

Here Christian theology and Medieval science appeared to be in conflict, and it took centuries to work out something like an acceptable solution. Bailey points to Albertus Magnus (c.1200-1280) as the first to propose this solution, but it was his pupil, Thomas Aquinas (1225-1274), who explained it as part of his masterful theological system which determined the course of the rest of Medieval European thought.[5] It is to Aquinas we will turn in the next section, exploring the Medieval solution to this conundrum.

Free Will and the Stars

In order to understand Aquinas’s explanation, we have to place ourselves in the Medieval mindset. To begin with, the distinction between material bodies and immaterial “intellectual substances” is important. In his Compendium of Theology¸ Aquinas begins his explanation of the influence with the stars by acknowledging the way higher bodies impact lower bodies:

“Among intellectual substances, therefore, some are divinely governed by others, that is, the lower by the higher. Similarly lower bodies are controlled, in God’s plan, by higher bodies. Hence every movement of lower bodies is caused by the movements of heavenly bodies. Lower bodies acquire forms and species from the influence thus exercised by heavenly bodies, just as the intelligible exemplars of things descend to lower spirits through higher spirits.”[6]

The way intelligible exemplars descend through spirits is not important. What is significant here is the simple acknowledgment that all material objects “lower down,” that is, towards the earth, are moved and shaped by heavenly bodies. The stars, being physical, effect physical things on earth. This might present a problem if one particular thing were not kept in mind:

“Furthermore, impressions left in lower bodies from the impact of heavenly bodies are natural. Therefore, if the operations of the intellect and will resulted from the impression made by heavenly bodies, they would proceed from natural instinct. And so man would not differ in his activity from other animals, which are moved to their actions by natural instinct. And thus free will and deliberation and choice and all perfections of this sort, which distinguish man from other animals, would perish.”[7]

So Aquinas succinctly states the problem: if the stars, through their actions on the physical things of the earth, also control our will and intellect, then we have no free will, no powers of deliberation, and are not to be distinguished from the animals. This is a high-stakes issue. All Biblical anthropology hangs on it.

Before we can take the next step with Aquinas, we have to step deeper into Medieval natural philosophy. Modern Christians tend to have a pretty simplistic explanation of what the soul is and what it does. Medievals had a more complex understanding. After acknowledging that man is a “rational animal,” that is, a living and moving being with the capacity to reason, C. S. Lewis goes on to explain the complexities of the human soul:

“Rational Soul, which gives man his peculiar position, is not the only kind of soul. There are also Sensitive Soul and Vegetable Soul. The powers of Vegetable Soul are nutrition, growth, and propagation. It alone is present in plants. Sensitive Soul, which we find in animals, has these powers but has sentience in addition. It thus includes and goes beyond Vegetable Soul, so that a beast can be said to have two levels of soul, Sensitive and Vegetable, or a double soul, or even—though misleadingly—two souls. Rational Soul similarly includes Vegetable and Sensitive, and adds reason.”[8]

All three kind or levels of soul are immaterial, but each Rational Soul in particular is directly created by an act of God, whereas as lower level souls possessed by animals and plants arise due to the inner workings of natural—though spiritual—forces.[9]

Just as our bodies have particular “faculties,” or abilities, such as a hand being capable of grasping or of punching or of lightly touching, so our souls have different faculties. Lewis goes on to describe two faculties of the rational soul in particular—intellect (intellectus) and reasoning (ratio):

“We are enjoying intellectus when we ‘just see’ a self-evident truth; we are exercising ratio when we proceed step by step to prove a truth which is not self-evident. A cognitive life in which all truth can simply be ‘seen’ would be the life of an intelligentia, an angel. A life of unmitigated ratio where nothing was simply ‘seen’ and all had to be proved, would presumably be impossible; for nothing can be proved if nothing is self-evident. Man’s mental life is spent in laboriously connecting those frequent, but momentary, flashes of intelligentia which constitute intellectus.”[10]

This means that man has both a faculty which completely overleaps sensory input (intellectus), and a faculty which joins these truths together and pushes them in new directions. Both these faculties belong to an immaterial part of man, one directly created by God, and not arising by natural processes. This allows Aquinas to resolve the problem of the effect heavenly bodies have on earthly ones:

“Nevertheless, since the will is not subject to the passions in such a way as necessarily to follow their enticement, but on the contrary has it in its power to repress passions by the judgment of reason, the human will is not subject to impressions emanating from heavenly bodies. It retains free judgment either to follow or to resist their attractions, as may seem to it expedient.”[11]

Thus, while man’s powers of growth, nutrition, and propagation may be effected by the heavenly bodies, or even his ability to sense the world around him, his will remains free. There is a rational core within man capable of resisting and even contradicting the influence of the heavenly bodies. Of course, not everyone has the strength of character to pull this off:

“Only the wise act thus; the masses follow the lead of bodily passions and urgings. For they are wanting in wisdom and virtue.”[12]

This has two important implications. First, astrology will still by and large be effective in predicting the general behavior of masses of humanity, even if it is not always accurate in predicting the actions of individual humans. Second, it is necessary to cultivate both wisdom and virtue to obtain true freedom from the forces of the world around you. Education, in the deeper sense of the term, is important.

The Legacy of the Solution

Aquinas, following in his teacher’s footsteps, provided a very sensible solution to the theological problem presented by the notion of astrological determinism. But while it may seem sensible, it was by no means universally accepted:

“Yet for various reasons this solution was not entirely successful. Doubts remained about the exact nature and extent of astral influence, and some authorities denied such influence altogether. The very skeptical theologian and natural philosopher Nicholas Oresme (ca. 1325-1382), for example, maintained that the astral bodies projected no forces toward the earth aside from light and heat.”[13]

In the centuries that followed, the discussion faded into obscurity. One the one hand, the issue of determinism was being fought over by Reformed theologians and Remonstrants who were much more concerned with salvation than the stars. On the other, the Copernican revolution so thoroughly altered our understanding of the structure of the solar system that the old explanations for the stars influenced the earth no longer applied. Both the theological and the scientific halves of the conundrum drifted apart into new contexts.

This calls into question just why we still object to astrology. It seems that the most obvious answer is simply that we believe it is unsupported by science. Modern natural philosophers have called the notion superstitious, and Christians have agreed with them, lumping the once respectable discipline in with tarot cards and palmistry. This objection, while perhaps more definitive, is far less interesting.

The beautiful thing about the theological conundrum that astrology presented was that it forced Christians to show how theology and science were related. For Medievals, these were not hugely divided disciplines which would never ordinarily interact. The world the Bible described and the world natural philosophy described were one in the same, and so theological issues were in fact very likely to have an impact on scientific views, and vice versa.

That, I think, is a sense of unity worth recovering—the idea that the God who made the heavens is the same God who was incarnate in the person of Jesus Christ, and so the truths of His world and the truths of his Word are not separate from one another. Perhaps it is good that the problem of astrological determinism died, but it also exactly the sort of theological-scientific problem we should expect to see in God’s universe.


[1] Michael D. Bailey, Magic and Superstition in Europe, pgs. 93-94.

[2] C. S. Lewis, The Discarded Image. (2009 printing from Cambridge University Press.) pg. 110.

[3] Lewis, pgs. 103-104.

[4] Bailey, pg. 98.

[5] Bailey, pg. 98.

[6] Thomas Aquinas, Compendium of Theology, translated by Cyril Vollert, with New Introduction by Richard Munkelt. Angelico Press. Pg. 133/chapter 127.

[7] Aquinas, pg. 134/chapter 127.

[8] Lewis, pg. 153.

[9] Lewis, pg. 154.

[10] Lewis, pg. 157.

[11] Aquinas, pg. 135.

[12] Aquinas, pg. 135.

[13] Bailey, pg. 98.

Dante, Courtly Love, and the Contemplative Life

This quarter in the eighth grade great books course I teach, we are spending several weeks on Dante’s Inferno. The class covers the medieval period in general, a period I find fascinating. And in some ways, Dante is the distillation of the best of medieval literature, cosmology, and theology. It’s fun.

Dante himself is quite the character. In the Divine Comedy, the work of which the Inferno is only the first third, he portrays himself wandering through a dark wood, plagued by vicious beasts, trying to get to the top of a mountain. He is met in those woods by the Roman poet Virgil, author of the Aeneid, who is going to take him through Hell, Purgatory, and Heaven to reach God. But it turns out that Virgil has been sent to Dante by Beatrice, the love of Dante’s life.

Fun fact: Dante met Beatrice when she was eight and he was nine, she married another man, and died three years later at the age of twenty-four. Dante had been married to someone else for five years at that point, and would end up having several kids with this other woman. Yet throughout his life, Dante maintained that he was madly in love with Beatrice, and had been since the day they met. He wrote a collection of love poetry in her honor that he published five years after she died, and finished the Divine Comedy, in which she had a starring role, only a year before his own death.

So, that’s interesting. Actually, it’s less weird than it sounds, if only slightly. This was the era of courtly love poetry, when falling in love with married women was the thing to do. In a lot of the stories of knights in shining armor fighting for the honor of fair ladies, said fair ladies were often married to another man. Now, a good Christian knight would never try to act on his love in an unbecoming manner–say, by sleeping with the lady whom he loved so madly. No, he would just admire her from afar, and fight in her honor. In theory. There was that whole Lancelot thing. Also Tristram and Isolde. And maybe one or two others. But most of the time it was platonic.

To modern sensibilities, this concept is wildly foreign. In what possible context could this be interpreted as a good thing, especially in the eyes of such a heavily churched culture, especially coming from such a self-consciously Christian guy as Dante? Well, there actually might be an explanation.

In the third part of the Divine Comedy, Paradiso, Dante ascends through the heavens one heavenly sphere at a time. Just as in Hell below, people are here placed into separate spheres based on their character. In the sphere of Mars, for instance, are those who fought for the faith. Above them, on Jupiter, are righteous rulers. But at the top, on Saturn, the last real planet in medieval cosmology, we find… monks?

Actually, this sphere is usually labeled “The Heaven of the Contemplatives.” Contemplatives are pretty much what they sound like–people who spend their lives in contemplation, either of God himself or of various divine mysteries. This would certainly include monks as we normally think of them, but it would also cover other people who led a similar lifestyle of meditation on holy things.

This is actually a huge part of the medieval view of the world. The best thing you could be was not one of those adventurous knights, not some righteous king like Arthur or Charlemagne, nor even necessarily a regular priest or bishop, caught up in the affairs of your parish or bishopric. No, medievals considered a life of contemplation to be the pinnacle of human existence.

There are several reasons for this, but one major reason is grounded in their philosophy of the soul. Medieval philosophy said that there were three kinds of souls–vegetable, animal, and rational. The vegetable soul was the kind of life that grew, but didn’t do much else. You know, like veggies. The animal soul belonged to life forms that could move around and act on their environment. But the last kind of soul, belonging to men and angels, and perhaps just a few others, was the rational soul. This kind of soul was capable of reason.

This view had certain implications. Lifestyles that primarily involved action, that involved working or fighting or other such things, were things we held in common with the beasts. Ruling, which engaged more of one’s reasoning abilities, would be higher up the chain. After all, you were using the faculties that distinguished you from lower creation. But higher up, higher even than wise and just rulers, would be people who did nothing but use their reasoning faculties. These were the people who contemplated the deep and holy things of life, using that faculty which God gave to his children and his servants above all others.

So what does this have to do with courtly love? Well, imagine a kind of love which was not focused on your merely animal drives, one which demanded instead that you meditate upon your beloved, use reason to contemplate her. Imagine, if you will, a contemplative rather than an active love. In fact, imagine a love where the actual activities of romance are ruled out, but not a higher and more platonic admiration. So, yeah, imagine you are in love with a married woman.

It’s kind of twisted, but it makes a weird sort of sense. If reason is the best part of our nature, and animal instincts to some extent reduce us to the level of beasts, then a love which is elevated to a solely rational level is a higher love. Of course, in practice it becomes something that is either creepy, if unrequited, or adulterous, if the lady returns your affections. It’s dangerous, and there’s no doubt it led to all sorts of excesses as well as some very sketchy fiction at the time. Dante even placed a couple adulterers in Hell who were inspired to sin thanks to reading courtly love poetry. But it does make that twisted sort of sense.

Now, no society is really simple, especially one as diverse and cosmopolitan, yet weirdly provincial, as medieval Europe could sometimes be. This little chain of reasoning no doubt leaves out quite a lot, and paints a very uneven portrait of a culture shaped by people from all sorts of backgrounds, with all sorts of weird quirks and personal histories. Still, it’s a striking and surprisingly coherent story. It’s just the sort of thing to make you wonder what weirdly alien practices we take for granted as a society, and how strange some of our values might be in the light of history. What might our descendants think of us seven hundred years from now?