"...thou hast ordered all thing in measure, number, and weight" (Wisdom 11:21).
So writes the author of the Apocryphal Old Testament book Wisdom--a text which captures so well the meaning and mystery behind number symbolism in the Middle Ages. Augustine himself suggests that numbers are like the thoughts of God, giving authority and approval to a system of thought that was to permeate medieval culture. Although on the surface number symbolism might appear to be on a par with symbolism from the natural world, there is a difference: both are based on God's signs in nature, but the significance of numbers involves a greater mystery and requires more education to unravel--at least in the more complicated forms prevalent in the Middle Ages.
In the history of medieval number symbolism there appear to be four distinct sources or influences. The first of these is probably the hardest to define and delineate because it is so fundamental: man's preoccupation with numbers from the beginning of time. Certain numbers were discovered early to be significant in nature: 2, a pair, 3, a family, 5, the hand. There are certain fundamental meanings drawn from human tradition itself that pass on into the more sophisticated number systems.
The second source for medieval number symbolism is Babylonian astrology. Here the focus is on the heavens--the movement and relation of the planets and constellations--on numbers derived from their study which had a sacred and mysterious significance. In this tradition 7 becomes a number of great significance--7 gods, 7 devils, 7 planets, 7 days-- and 12 becomes associated with the signs of the zodiac and astrological predictions. From the astrology and magic of Babylonia come sacred numbers shrouded in mystery and awe that are then passed on to the Middle Ages.
Paralleling some of the developments in Babylonian astrology, the numbers found in the Old and New Testaments comprise the third source of number symbolism. Seven, eight, and twelve were significant numbers in the Old Testament which were also repeated in the new. What particularly fascinated some of the early Christian thinkers was that the numbers in Sacred Scripture were the same numbers they saw in Babylonian astrology. Such a parallel between pagan and Christian not only encouraged study of the biblical numbers but gave a credibility to the findings of the pagan astrologers.
Independently in Greece there developed another system of numbers known as Pythagoreanism, which is the fourth important influence on medieval number symbolism. Unique to this system are two principles which greatly influenced subsequent thought. The first is that all numbers and, as a corollary, all things are contained in the decad. From this principle grew the idea of the cosmic universe as being comprised of the 9 spheres plus a "counter earth" which bring the total to the desired 10. The second principle, what of viewing mathematics geometrically, helped to create a link between tangible reality and number theory. Even a cursory look at Pythagorean theory is enough to see the rich complexity of the relations and meanings of numbers. For them 6 becomes the first perfect number because it is the sum of 1+2+3, and other numbers gained similar significance as they sought in numbers the key to the mysteries of the universe.
With the pervasiveness and power of these four sources, it is small wonder that number symbolism becomes so significant in the Middle Ages. Although the interest in numbers can be seen in Early Christian thinkers such as Philo Judaeus (1st century A.D.), who discovered Pythagorean numbers in Genesis, and the Gnostics (1st century B.C. to 5th century A.D.), who developed elaborate and mystical systems, the most important proponent for Christian number symbolism was St. Augustine. It was Augustine who fused the pagan and Christian to suggest that number was a principle of God's created order. By studying numbers, therefore, as one studied animals, plants, and stones, one could learn something of the Divine Wisdom. Especially could one hope to learn truth by studying the sacred numbers of the Bible, and through Augustine's stamp of approval and encouragement, later Church thinkers began to search out the meanings of such numbers as the 12 disciples, the 70 palm trees of Elim, the 318 servants of Abraham, and the 144,000 of the Apocalypse. In time these interpretations became standardized, and other writers such as Isidore of Seville, Liber numerorum (Book of Numbers), Hugh of St. Victor, Hrabanus Maurus, and Odo of Morimond's Analytica numerorum in theographiam (An Anatomy of Numbers for Divine Writings) passed on this Christian numerical symbolism to succeeding generations.
It should be obvious that the interpretation of numbers--and especially numbers in Scripture--was a fine art, requiring much education, but traces and results of these interpretations filter into every area of medieval thought. "Number," Bonaventure says, "is the supreme exemplar of God," and therefore man, if he wishes to learn about God, must understand the significance of numbers. Numbers came to be a part of man's life in the Middle Ages--in the mass, in cathedral architecture, in the works of vernacular literature, and although common man could not hope to understand the intricacies of number symbolism or to work out elaborate interpretations, enough of the basic significance of numbers filtered down through medieval culture to let him see something of God's sacred numbers. There were 10 commandments, 7 deadly sins, 3 persons of the Trinity, and 5 joys of Mary.
Numbers did matter--and for that reason they are significant in the art and literature of the period. It is certainly true that not every number in a work of art is significant symbolically any more than every animal, or color, or plant has a deep meaning. Sometimes an author will use a figure such as 100 or 1,000 to suggest a large number. But when an author uses a specific number in a conspicuous way, the reader needs to consider the symbolic possibilities. Chaucer, for example, specifically tells us that there are 29 pilgrims going to Canterbury. Critics have added and re-added and re-figured the number of pilgrims, but they have missed the point. As Edmund Reiss points out, 29 is a number just short of 30. Since 30 is a number of perfection because it is a product of 3 (the number of the Trinity) and 10, 29 becomes a number approaching perfection--an ideal number to suggest the idea of pilgrimage.
Many critics have analyzed the numbers in Dante's Commedia as well as considered the numerical structure of the entire work. The whole Commedia is comprised of 100 cantos with 33 for the Inferno, 33 for the Purgatorio, and 33 for the Paradiso, plus one canto of introduction, giving a total of 100. Such an ordering based on the numbers of the Trinity (3), the unity of the Trinity (1), plus the perfection of 10 and factors thereof could not have been an accident. Other critics have analyzed the number of lines in the whole work and have found important significance in the middle line of the middle canto in the whole work. Also the terza rima, the three line interlocking stanza form Dante uses, proclaims the mystery of the Trinity in yet another way. Clearly Dante understood number symbolism and used it to good advantage. Surely not every work of medieval literature will have the complicated numerical structure of this great work, but an awareness and understanding of medieval number symbolism will help to appreciate the deeper significance of a work.
Bullinger, Ethelbert W. Number in Scripture. 1894. Grand Rapids: Kregel Publishers, 1971. 220.851 B874n 1967
This work does not do as much with the theory of number symbolism as some of the other works listed here, but it does do a good job of discussing the scriptural meanings for all the basic numbers. He also includes long lists of the times a specific number occurs in the Bible.
Hopper, Vincent Foster. Medieval Number Symbolism. New York: Columbia University Press, 1938. 133.335 H778m
While this work is not set up as a dictionary of number symbolism, it is clearly the standard work on the subject. In addition to providing a detailed discussion of the development of medieval number symbolism, he includes a good index which helps to locate the meaning of specific numbers. There is also a good bibliography, although dated.
Kinney, LeBaron W. The Greatest Thing in the Universe. New York: Loizeaux Brothers, 1939. 220.6 K623g
Although this work does tend to preach a little, it goes through the major numbers and gives their significance according to the Bible. He also gives good listings of the numbers and their locations in the Bible.
Meyer, Heinz. Die Zahlenallegorese in Mittelalter. München: Wilhelm Fink Verlag, 1975.
Although this work is in German, a student who reads a little German will find this work helpful. It focuses on the patristic and exegetical philosophy of numbers and also gives the principles of number symbolism. Most important it gives a detailed listing of symbolism for the major numbers between 1 and 1000 and even a few over 1000.
Child, Heather and Dorothy Colles. Christian Symbols Ancient and Modern.
Cirlot, J. E. A Dictionary of Symbols.
Cooper, J. C. Illustrated Encyclopedia of Traditional Symbols.
Ferguson, George. Signs and Symbols in Christian Art.
Forstner, Dorothea. Die Welt der Symbole.
Hulme, F. Edward. The History Principles and Practice of Symbolism in Christian Art.
Metford, J. C. J. Dictionary of Christian Lore and Legend.
Reau, Louis. Iconographie de L'Art Chretien.
Sill, Gertrude Grace. A Handbook of Symbols in Christian Art.
Vries, Ad de. Dictionary of Symbols and Imagery.
Selected Secondary Sources
Masi, Michael. Boethian Number Theory: A Translation of the De Institutione Arithmetica in Studies in Classical Antiquity, vol. 6. Amsterdam: Rodopi B. V., 1983.
Most. William G. "The Scriptural Basis of St. Augustine's Arithmology" Catholic Biblical Quarterly 13 (1951): 284-95.
Reiss, Edmund. "Number Symbolism and Medieval Literature." Medievalia et Humanistica n.s.1 (1970): 161-71.