Semester Analysis (Part 6)

Ever since I began reading poetry in adolescence, I had a somewhat overwhelming interest in pinpointing each and every symbol layered in the verses.  I wanted to know why the poet had put them there, what they represented, and what they added to the overall message.  What was the “Tyger”?  Why did he burn bright?  What could it mean!  Coincidentally, that perspective had stunted by ability to enjoy the poetry I was reading.  Over the years, I’ve come to understand poetry as a much more experiential journey.  One must taste the words that slip over the tongue, feel the breath of the rhyme against one’s lips, and softly listen to the sounds ring within the ears.  Still though, I can’t seem to shake that ever present desire to dive deeper, and that feeling presents itself even more fully in the poetry of Dante.

This course was my 2nd in Dante studies, the 1st being an undergraduate course at a secular university that emphasized the narrative, rather than the theological aspects.  Nevertheless, I got a good feel for the story and the socio-political commentary.  My time spent over the last few months with Dr. Mahfood and my peers has revealed a much deeper understanding of the poem.  I wanted my semester project to provide similar perspective.

In my project, I wrote, “Three beasts, nine circles, thirty-three cantos—they seem so important, and almost familiar, yet their meaning eludes us.  Although the reader may not understand the purpose of such symbolic connections, they recognize that Dante is softly whispering in their ears.”  Essentially, this is why I choose the topic of Numerology in the Comedy—I heard Dante whispering in my ears, and I wanted to hear him more clearly.

Reflecting on my choice a few months later, I couldn’t be happier.  My exploration of numerology took me on a journey from Pre-Socratic philosophers, to Church Fathers, and finally to Dante himself.  It was beautifully illuminating to learn about the Pythagoreans, and the ancient origins of the numerology that Dante adopted.  These men saw elegance in a theory of being that was constructed through numbers.  They recognized that music was produced by certain mathematical ratios, and logically concluded that numbers were the fundamental structures of reality.  The Church Fathers saw things differently—in fact, they recognized an intimate connection between particular numbers and their relationship with the divine.  The number “four” represented the worldly, “eight” represented the Resurrection, “eleven” represented transgression—and through these connections they drew layers of beauty out of Scripture.  Dante masterfully adopts these meanings and builds them—many times subtly (did you notice the noble castle has 7 walls?)—into his verse.  When I think back on what I learned, the fact is that a number of doors have been cracked open, and I see the light shining through.  Much deeper understands lies behind them!

There is certainly hope for the future of my project topic!  As I related in my introductory post to the course, the Divine Comedy played a significant role in my decision to seriously study my faith, and to that end has ignited a passion within me to share the story with others.  It’s been a goal of mine to teach the Divine Comedy to undergrads, so that maybe I can help them reinvigorate their faith the same way that mine was.  Education is a long journey, but it is an experience that continuously builds upon itself, and this project was another building block, of which there will be many more.

Addendum:  What has the Paradiso added to my project?

Having read the Divine Comedy previously, I incorporated aspects of the Paradiso within my project, even though we hadn’t reached it yet in the course.  Yet, the concepts found there are worth repeating here. Like Dr. Mahfood had said, the Paradiso helps us better understand the previous two canticles.  It is the answer key to the cipher that is the Divine Comedy.  In my project, I spent time developing the significance of the number 11—transgression—and how Dante wove meaning into the 11th canto of each canticle.  Inferno 11 catalogs the different categories of sin, Purgatorio 11 highlights the arch-sin, pride.  Finally, Paradiso 11 explains to us that one must counter pride by practicing the ultimate virtue—humility.  A reading of the first two canticles renders our understanding of Dante’s message inadequate.  The Paradiso completes the masterpiece.

Conclusion (Part 5)

Tracing the history of numerology from its origins in the Pythagoreans to its application to the Divine Comedy provide incredible depth and understanding to the messages that Dante is trying to communicate.  Dante has buried in his works, clues that readers for centuries have been slowly discovering.  Like an archaeological expedition, we slowly, decade after decade, make small discoveries that give us a fuller understanding of the original author and his greatest work.  By studying the origins of ideas that where prominent during his time period, we earn the ability to gain greater insight into the genius inherent in the Comedy.

Dante’s Application of Number-Symbolism in the Divine Comedy (Part 4)

Dante masterfully applies the tenets of medieval numerology which infuses both the structure of his realms and his characters with much more depth than a simple surface narrative would suggest.  Two notable uses of number-symbols applied to the structure of the Comedy include Dante’s cross-canticle use of the number eleven and the patterns found at the center of the Comedy, Purgatorio XVII.  In all of the Comedy, Dante only makes explicit mention of the number eleven once, in the tenth bolgia of the eighth circle of hell.  The mention is in reference to its size:  “…although it turns for eleven miles and is no less than half a mile across” (Inferno 30.85-86).  Furthermore, in the previous bolgia, Dante gives us another indication as to geographic size:  “…think, if you believe you could number them, that the valley turns for twenty-two miles” (Inferno, 29.7-9).  By using a multiple of eleven, not only is Dante giving us clues to the size of each circle relative to one another, he is more importantly linking the structure itself to the root number eleven, a number filled with transgression.  A handful of traditions trace the origin of transgression to the number eleven, two of which will be familiar with most readers.  In pre-Christian times, God gave the Jewish people the Decalogue, ten core laws to govern behavior and morality in accordance with the desires of God.  The number eleven signifies a “stepping past” the Decalogue—a transgression of its tenets.  According to a different perspective, the number twelve represents the fullness of apostolic truth as it aligns with the number of the apostles chosen by Christ.  Note that upon the transgression of Judas, only eleven apostles remained, and this state was quickly amended by selecting Matthias to succeed Judas.  The Venerable Bede keenly summarizes: “For eleven, which goes beyond ten but does not reach twelve, that is, the apostolic number, signifies transgression of the Decalogue of the Law.”[1]  The clever reader of the Comedy will immediately notice another connection with the number eleven through cross-canticle readings of Inferno XI, Purgatorio XI, and Paradiso XI.  Dante reserves the whole of Inferno XI for an exposition of the types and degrees of sin that are punished in hell, and orders them in relation to how greatly they offend God.  Thus, the theme of Inferno XI is the concept of sin itself (not merely an exploration of a particular sin).  Purgatorio XI again addresses sin, but a very particular type of sin, pride.  In fact, pride is the ultimate sin, which informs and promotes all other types of sin.  For the moment we turn our eyes from the desires of God to the desires of ourselves, sin starts to grow within us.  Thus, where Inferno XI catalogued sin, Purgatorio XI teaches us of that sin from which all other sins flow.  Finally, Dante beautifully closes his cross-canticle exploration of sin in Paradiso XI, where humility, the counter-virtue of pride is given treatment by Thomas Aquinas illuminating the person of St. Francis of Assisi.[2]  Thus, not only does Dante build the structure of hell on the number eleven, but he uses it throughout each realm to explain the nature of sin and how to conquer it.

One may suspect that the center of the Comedy, Purgatorio XVII, may hold special significance.  In fact, this canto along with canto XVI and canto XVIII form a cross-canto exploration of two themes, love and free will.  Beyond literally being the structural center of the Comedy, Dante uses symbolic numbers to call our attention to these themes as being the most important themes of the entire work.  After analyzing the text, we find that these themes are framed by two particular terzine that make mention of free will.  Within Marco Lombardi’s discourse, exactly twenty-five terzine prior to canto seventeen, he says, “If that were so, free choice would be destroyed in you, and it would not be justice to have joy for good and mourning for evil” (Purgatorio 16.70-72).  Symmetrically, we see another mention of free will exactly twenty-five terzine after Canto seventeen as well.  Virgil says, “This noble power Beatrice understands as free choice, and therefore see that you remember it, if she speaks to you about it” (Purgatorio 18.73-75).  As medieval number theory would have us do, we must sum the digits of twenty-five (the number of terzine on either side on canto seventeen).  That they sum to seven, the number of completeness, is significant.  It is as if Dante is calling direct attention towards the terzine between these two points, and emphasizing that the themes of free will and love represent the culmination of his entire journey.  Furthermore, the seven central cantos in the Purgatorio have a distinct pattern of line numbers:  151, 145, 145, 139, 145, 145, 151.  Again, summing the digits of each line count we get:  7, 10, 10, 13, 10, 10, 7.  On the ends, the number seven is seen framing these seven canti and representing their completeness.  Inside the frames, on both sides, is the number ten, representative of perfection.  The center canto’s sum, 13, seems not to have any particular significance outside of the fact that one hundred thirty-nine lines implies that the central terzina of that canto will be the number seventy, whose digits sum to seven, once again reflecting completeness.  As Singleton notes, “the area of these 7 cantos holds the experience of a ‘conversion’…variously presented in explicit statement and in imagery…[concerning] the radical difference that there is between possessing earthly goods and possessing heavenly goods.”[3]  Singleton’s relatively recent discovery illustrates the depth to which Dante infused his Comedy with number-symbols.  In doing so, it helps the reader—even 700 years later—discover layers of meaning that aren’t found on a surface reading.

Beyond structure, Dante also uses symbolic numbers to provide meaning to individuals, or groups of individuals.  Upon arriving in Limbo, Dante is met by great men of the past—Homer, Horace, Ovid, Lucan—and is made “sixth among so much wisdom” (Inferno 4.101-102).  Being one of his earliest experiences in hell, it’s odd that he has such a positive experience.  For a man like Dante, this is one of the greatest honors he could achieve.  We will see this juxtaposition of negative (being in hell) and positive (lauded by the poets) infuse the story with meaning throughout this canto.  Shortly after meeting the poets, Dante comes upon “a noble castle, seven times encircled by high walls, defended all around by a lovely little stream” (Inferno 4.106-108).

Yates Thompson 36, Limbo

The Poet makes explicit reference to “seven” walls, reminding us of the symbolic meaning of completeness.  Noted Dante scholar, Charles Singleton, explains, “Probably the noble castle is best understood as the Castle of Fame, special dwelling of those whose ‘honored name’ has won them a privileged place in Limbo.  In that case the seven circles of walls, each with its gate leading to the castle, may well represent the seven liberal arts, and perhaps also the seven virtues, moral and intellectual, so well known to the pagans.”[4]  This episode is odd in a sense that even though we’re early on in hell, we see a reference to “completeness.”  If these men are complete, why are they in hell?  To that end, we must explore what other mention Dante makes of these pagans.  He tells us that “…people worthy to be honored possessed that place” (Inferno 4.71-72), but that “…they did not receive baptism, which is the gateway to the faith that you believe” (Inferno 4.35-36).  In fact, we see Dante repeatedly referencing a “falling short” of these virtuous pagans.  “I am Virgil, and for no other crime did I lose Heaven than for not having faith…not for doing, but for not doing have I lost the sight of the high Sun…there I dwell with the innocent little ones” (Inferno 7.7-8, 7.25-31, emphasis added).  Guzzardo explains, “They have been given a privileged place in Limbo precisely because these great men embody all the human qualities necessary for salvation except for one shortcoming:  they lack that faith of which Baptism later became the sign.”[5]  Therefore, if we recall the symbolic representation of the number eight, baptism and salvation, we can see a beautiful positioning of completeness, in the sense that they were virtuously complete, yet they were lacking one thing, faith in a Redeemer or the Sacrament of Baptism which represents that faith.  The seven walls actually represent a lacking on the part of the virtuous pagans.  They accomplished everything they could through their humanity, but still fell short in their faith, and lost their salvation.[6]


[1] Victoria Kirkham, “Eleven is for Evil:  Measured Trespass in Dante’s Commedia,” Allegorica:  A Journal of Medieval and Renaissance Literature Vol. 10 (1989), 31-32.

[2] Kirkham, “Eleven is for Evil,” 28.

[3] Charles S. Singleton, “The Poet’s Number at the Center,” Modern Language Notes Vol. 80, no. 1 (1965), 1-10.

[4] Guzzardo, Numerological Studies, 42.

[5] Guzzardo, Numerological Studies, 47.

[6] Guzzardo, Numerological Studies, 53.

Christian Application of Numerology (Part 3)

Where the Pythagoreans saw in numbers reflections of the material and mystical world, Christians saw in numbers the representation of scriptural truths.  In time, certain numbers would become imbued with a vibrant symbolism, ranging from fairly intuitive meanings to complex meanings.  The number one, similar to the Pythagorean belief, represents the oneness and unity of God—the ultimate principle—defined in the Shema, “Hear, O Israel: The Lord our God is one Lord” (Deut 6:4, RSV).  The number one also plays a further role, the addition of one to something else raises that something else to perfection.  For example, Dante’s realms have thirty-three cantos each summing to ninety-nine total cantos.  The addition of an introductory canto (the Dark Wood) raises the entire work to perfection.  Conversely, the number two is generally negative, it represents a departure from the unity of the number one.  Scripture provides us with an illustration:  “Take with you seven pairs of all clean animals, the male and his mate; and a pair of the animals that are not clean, the male and his mate” (Gen 7:2, RSV).  As we’ll see, the number seven is positively linked with the clean animals, but the number two is associated with the unclean animals.  Furthermore, the second day of creation is the only day which God does not explicitly state that he saw it as good.  The number three has a clear connection with the Trinity, and thus represents perfection and completeness.  Four is connected with worldly things.  We have the four directions, the four seasons, and the four Gospels (to guide man towards God).  Similarly, the number five is associated with carnality because of our five senses.  Many of these symbolisms we as modern readers already know.  There is some remnant of these ideas left in our culture, but even if we did not know them, we should now be awakened to the clarity of these connections.  The next set of symbolisms become more complex.  Many modern readers are aware of a connection with the number seven and something positive like “Lucky 7s.”  The number seven functions much like the number three in that it expresses completeness and universality, but to truly understand why, we must consider that seven is the summation of the numbers three and four.  Taking what we’ve learned, seven is the combination of the spiritual (represented by three) and the worldly (represented by four).  We now think immediately to other combinations of spiritual and worldly—the body and soul, the theological virtues and cardinal virtues (of which there are 3 and 4 respectively).  Drawing a further connection, Scripture reminds us that there were seven days of creation.  We now have a fuller understanding of the origins of the importance of the number seven.  Another more complex number is eight.  Traditionally, eight is the number representing baptism, redemption, and new life.  Not immediately evident as to why, we must look back again to the Book of Genesis.  God created the world in six days, and rested on the seventh day.  Tradition tells us that the eighth day represents the coming and salvific actions of Christ.  It is thus the eighth day of creation—the ushering of the age of redemption for the sins of mankind.[1]  This important number has beautifully influenced Christian art and architectural developments over the ages.  Baptismal fonts are generally octagonal, reinforcing the connection of the number eight with baptism.  Additionally, baptisteries attached to churches have traditionally had eight sides.  Saint Ambrose, Bishop of Milan, wrote of an octagonal baptistry that was near the church of St Thecla at Milan:

Eight-sided is the lofty shine to match its sacred use;
Eight-angled is the font to show its benefits profuse;
With such a number grace and life supplanted human guilt
And with such number must the hall of baptism be built[2]

Finally, there was a common hand gesture to represent the number eight: “the third and fourth fingers are lowered and the first and second fingers and the thumb are raised.”[3]  We are familiar with Christ often depicted using this hand gesture, representing the ushering of the port-resurrection age.

Post-Resurrection hand gesture

Finally, there are some rather complicated symbolisms in which we must rely on the early Church fathers to help illuminate their truths.  St. Augustine, commenting on the Book of John, explains the significance of the one hundred fifty-three fish caught by John in chapter twenty-one.  He notes that one hundred fifty-three is the triangular number of seventeen.  A triangular number is one of a sequence of numbers that form the pattern of an equilateral triangle, and is found through the formula:  Xn=x(x+1)/2).[4]

Triangular numbersThe first five “Triangular” numbers

He then exposits that the number seventeen is the summation of seven (which represents the divine) and ten (which represents the number of the Decalogue).  He concludes that this catch was “divine providence.”[5]  Another example concerns the numbers thirty and sixty.  St. Jerome explained that the meaning of these numbers is derived from the hand gestures of married couples and widows.  Regarding thirty, “’the very joining of the fingers, as if embracing each other in a tender kiss and unity, depicts husband and wife.’  Widows were sixty, and in this gesture the index finger presses down on the thumb ‘the greater the difficulty of abstaining from the enticements of pleasure once experienced, so much the greater the reward.’”[6]  Augustine claims that we should hold numbers in high regard, since scripture makes it apparent that they have meaning imbued by God.[7]  Boethius claimed that numbers could guide the mind “from perceptible things to the invisible truth in God: from the material to the immaterial.[8]  This large-scale Christian adoption of the symbolic meanings of numbers inspired Dante to consider their importance throughout many of his works.


[1] John J. Guzzardo, Dante:  Numerological Studies (New York: Peter Lang, 1987), 121-134.

[2] Morrison, “Art of Number Symbolism,” 174-175.

[3] Morrison, “Art of Number Symbolism,” 177.

[4] “Triangular Number Sequence.”

[5] Morrison, “Art of Number Symbolism,” 172.

[6] Morrison, “Art of Number Symbolism,” 172.

[7] Morrison, “Art of Number Symbolism,” 181.

[8] Morrison, “Art of Number Symbolism,” 171.

Origins of Numerology (Part 2)

We begin our exploration of numerology with the Pythagoreans.  The Pythagoreans were an ancient religio-philosophic society founded in southern Italy in the 6th century, and are regarded as one of the groups of “pre-socratic” philosophers.  Their philosophical beliefs had a profound influence on their moral tenets.  For example, they held the doctrine of metempsychosis—the belief that the soul does not die, but transmigrates from one body to another–even animal bodies.  Their prohibition of eating the flesh of animals then, follows logically.  A legendary story tells us “how Pythagoras, seeing somebody beating a dog, told him to stop, since he had recognized the voice of a friend in the yelping of a dog.”[1]  Yet, their most important contributions came in the areas of mathematics and music.    They noticed that underlying the harmonies and melodies in music was a series of numerical ratios, and the proper combination of these ratios produced a certain quality of sound.  It stands to reason then that music was made of numbers.  In fact, they took this concept, and extended it to the whole of the universe and everything in it.  Numbers were not simply abstract concepts, they were spatial truths.[2]  The number one represented a point with no dimensions, and was named the “monad.”  Two points joined together creates a line–representing the first step into spatial thinking, called a dyad.  Three points join lines together to create the surface plane, a two-dimensional object.  Finally, four points completes the fundamentals of spatial generation, and gives us the solid, three-dimensional object.  Thus, being itself, in our three-dimensional world, is created through the combination of points, lines, and solids.  To that end, the τετραχτυς (tetraktys), a figure represented by the summation of the first four numbers, was a sacred figure.[3]

File:Tetractys.svg“Tetraktys”

The Pythagoreans also began the process of assigning symbolic meaning to numbers.  The monad became the ultimate unit of being because of its fundamental structure in reality.   Four became symbolic for material bodies because it follows from the points, lines, and solids represented by the first three numbers.  Five is the symbolic number of marriage, following from the combination of two (the first feminine number) and three (the first masculine number).[4]  They viewed the number three “as masculine and strong, as [it] cannot be divided evenly” and the number two “as feminine and weak, as [it] is easily split.[5]  The number ten represented the limit of all creation because it was the sum of the components of the τετραχτυς: 1+2+3+4=10.[6]  Thus, for the Pythagoreans, numbers represented both the fundamental structure of reality as well as having a mystical significance through symbolism.


[1] Frederick Copleston S.J., A History of Philosophy – Volume 1:  Greece and Rome (New York: Doubleday, 1993), 31.

[2] Copleston, A History of Philosophy, 33.

[3] Copleston, A History of Philosophy, 34.

[4] Copleston, A History of Philosophy, 35-36.

[5] Alessandra C. Cusimano, “Importance of Medieval Numerology and the Effects Upon Meaning in the Works of the Gawain-Poet.” (M.A. diss., University of New Orleans, 2010), 4.

[6] Tessa Morrison, “The Art of Early Medieval Number Symbolism,” Journal of the Australian Early Medieval Association Vol. 2, 170.

Introduction (Part 1)

Readers of Dante’s Divine Comedy recognize that below the surface narrative lie layers of meaning—from political commentary to theology to the experience of a moral journey.  Yet, they are often subtly aware that there is even more in play than they quite perceive, and many times that awareness centers around a certain number that keeps showing up, or a pattern they’ve noticed within the numbers.  Three beasts, nine circles, thirty-three cantos—they seem so important, and almost familiar, yet their meaning eludes us.  Although the reader may not understand the purpose of such symbolic connections, they recognize that Dante is softly whispering in their ears.

The brilliant mind of Dante placed both overt and subtle references to symbolic numbers throughout the Comedy, the problem with our recognizing them is that Dante wrote for an audience that lived many hundreds of years ago.  When modern readers experience the Comedy, they approach it with a contemporary interpretive lens, which obscures or completely misses references that a 14th century reader would have readily grasped.  In order to truly understand the depth of symbolic references that Dante provides, we must educate ourselves on the recognized meanings of particular numbers—but even more than that, we must recognize the philosophical and scriptural origins of these meanings.  Our goal is to systematically build understanding by exploring the history of numerology, its adoption by Christianity, and then look at how Dante uses numerical symbolism to deepen the meaning of both the structure of his realms, but also how he applies symbolic numbers to persons.

Final Project Thesis and Annotated Bibliography

Thesis Statement

A strong tradition of medieval numerology–the attribution of special meaning to common numbers and ratios–pervades all three canticles of Dante’s Divine Comedy.  Dante uses these number-symbols to help paint his realms with deeper meaning than a mere surface reading of the Comedy would suggest.

Annotated Bibliography

Alighieri, Dante. Inferno, translated by Robert M. Durling.  Oxford University Press:  New York, 1996.  Primary text with which to explore Dante’s application of numerology.

Alighieri, Dante. Purgatorio, translated by Robert M. Durling.  Oxford University Press:  New York, 2003.  Primary text with which to explore Dante’s application of numerology.

Copleston, Frederick S.J.  A History of Philosophy – Volume 1:  Greece and Rome.  New York: Doubleday, 1993. Copleston dedicates a chapter of his History to the Pythagoreans–one of the earliest influences of later Christian numerology.

Cusimano, Alessandra C. “Importance of Medieval Numerology and the Effects Upon Meaning in the Works of the Gawain-Poet.” M.A. diss., University of New Orleans, 2010. This paper discusses a brief history of medieval numerology as well as examining specific examples, such as Divine Proportion.

Guzzardo, John J.  Dante: Numerological Studies.  New York: Peter Lang, 1987.  My primary research text–a scholarly work providing a number of essays of different numerological topics as well as an appendix which provides evidence for the origin on meanings applied to certain numbers.

Kirkham, Victoria. “Eleven is for Evil: Measured Trespass in Dante’s Commedia.”Allegorica: A Journal of Medieval and Renaissance Literature Vol. 10, (1989): 27-50. This article takes a detailed look at the significance of the number 11.  The roots of the symbolism are traced, as well as the application of the number 11 to the Divine Comedy, drawing parallels between the 11th canti of each realm.

Morrison, Tessa. “The Art of Early Medieval Number Symbolism.” Journal of the Australian Early Medieval Association Vol. 2: 169-181. This article explores the traditions in which Christian symbolism developed, and how important numerology was as a model for theology and creation.

Singleton, Charles S. “The Poet’s Number at the Center.” Modern Language Notes Vol. 80, no. 1 (January 1965): 1-10. Singleton’s article explores the structure of hell, purgatory, and paradise in relation to certain significant numbers, such as 7.  It also addressed the importance of the central canto of the central cantica, Purgatorio, Canto 17.

“Triangular Number Sequence” at MathIsFun, 2011, at http://www.mathisfun.com.  A webpage explaining the concept of a “triangular number.”

Original Project Thesis and Annotated Bibliography

Thesis Statement

A strong tradition of medieval numerology–the attribution of special meaning to common numbers and ratios–pervades all three canticles of Dante’s Divine Comedy.  Dante uses these number-symbols to help paint his realms with deeper meaning than a mere surface reading of the Comedy would suggest.

Annotated Bibliography

Chapman, Coolidge Otis. “Numerical Symbolism in Dante and the Pearl.” Modern Language Notes Vol. 54, no. 4 (April 1939): 256-259. Chapman touches upon a few key number-symbols in the Divine Comedy, especially regarding the number three.

Cusimano, Alessandra C. “Importance of Medieval Numerology and the Effects Upon Meaning in the Works of the Gawain-Poet.” M.A. diss., University of New Orleans, 2010. This paper discusses a brief history of medieval numerology as well as examining specific examples, such as Divine Proportion.

Guenon, Rene. The Esoterism of Dante. Hillsdale: Sophia Perennis, 2001. Chapter 7 in this book discusses number symbolism in the Divine Comedy, specifically addressing the numbers 11, 22, 515, 666, and the ratio of 22/7—the ratio between the circumference and diameter of a circle.

Kirkham, Victoria. “Eleven is for Evil: Measured Trespass in Dante’s Commedia.”Allegorica: A Journal of Medieval and Renaissance Literature Vol. 10, (1989): 27-50. This article takes a detailed look at the significance of the number 11.  The roots of the symbolism are traced, as well as the application of the number 11 to the Divine Comedy, drawing parallels between the 11th canti of each realm.

Morrison, Tessa. “The Art of Early Medieval Number Symbolism.” Journal of the Australian Early Medieval Association Vol. 2: 169-181. This article explores the traditions in which Christian symbolism developed, and how important numerology was as a model for theology and creation.

Rendall, Thomas. “The Numerology of Dante’s Divine Vision.” Explicator 68, no. 3 (July 2010): 151-154. A short article analyzing numerology in the Divine Comedy with a special focus on the numbers three and four.

Singleton, Charles S. “The Poet’s Number at the Center.” Modern Language Notes Vol. 80, no. 1 (January 1965): 1-10. Singleton’s article explores the structure of hell, purgatory, and paradise in relation to certain significant numbers, such as 7.  It also addressed the importance of the central canto of the central cantica, Purgatorio, Canto 17.