In the first millenium BCE, Pythagorean number philosophy was developed. Though the texts and theories that are attributed to Pythagoras are much later, its possible they have some provenance within the early Pythagorean movement. Of the many elements of Pythagoreanism, one of the most fascinating is arithmology, the study of Pythagorean numerology. Pythagorean numerology largely hinges on the concept of the decad, or tetrakys. “Ten, according to the Pythagoreans, is the greatest number- as well as for that is the Tetractys, as that it comprehends all arithmetical and harmonical proportions.”¹The decad corresponds to the entire cosmos. There are a number of ways to understand them, even within the Pythagorean and Platonist movements.² The attributes of each of the numbers of the decad that are given in this article can be useful to a beginner to get a very limited idea about arithmology. After looking over the terms, it is highly suggested that Nicomachus of Gerasa’s Arithmetic and Iamblichus’s Theology of Arithmetic be studied. Additionally, two modern books on Pythagoreanism, Thomas Stanley’s Pythagoras and The Pythagorean Sourcebook, are indispensable. The keyword lists would be useful to students who have a concept of arithmology after studying these texts. It should be stressed that the keywords only give a glimpse to a beginner and the study of arithmology entails much more. The qualities of numbers, linguistics, and the reasoning behind the associations given below are some of the elements of arithmology.
Short of having certain ancient texts or compilations of them, some of this information might be difficult to obtain on the internet. The keywords that are associated with each number of the decad are included below. Hopefully, infographics will be made at a later date and shared on this website. An easy way to engage the decad can be to study and do rituals for each number of the decad per day, starting with either the decad and ending at the monad or starting at the monad and ending at the decad. Alternatively, each number of the decad could be assigned an allotment of 10 days. Numerous other approaches could be devised. Also, if it is to be included in a practice, it should accompany readings in Pythagorean and Platonist literature, and a few texts mentioned in the Bibliography section should be a good place to start. As for numeric schemes for studying the decad, if there is time, one could create a hundred days ritual to be followed by a ten days ritual. Another way to do it might be to start with the decad for ten days, then the ennead for nine days, the octad for eight days, and so forth, ending with the monad in one day. After alloting days to the numbers of the decad, they could be the subject of a ritual that takes place for ten hours of a day, with one hour given to each number. Going even smaller, one hour and 40 minutes could be allotted to the numbers of the decad as well, so that each number gets ten minutes. There are a number of approaches to use for getting familiarity with the decad in a spiritual and ritual context. The keywords are listed below.
The Decad
The Monad
Instrument of Truth
Obscure
Not-Many
A Chariot
Male-Female
Immutable Truth and Invulnerable Destiny
A Seed
Fabricator(demiurge)
True Happiness(eudaimonia)
Zeus
Life
God
The Equality in Increase and Decrease
Memory
A Ship
Essence(ousia)
The Inkeeper(pandokeus), “that which takes in all”
The Pattern or Model(paradeigma)
The Moulder
Prometheus
The First(Proteus)
Darkness
Blending
Commixture
Harmony(symphonia)
Order(taxis)
Materia
A Friend
Infinite Expanse(chaos)
Space-Producer
The Dyad
Inequality
Indefinite(aoristos)
The Unlimited(apeiron)
Without Form or Figure
Growth
Birth
Judgment
Appearance
Anguish
The Each of Two
Falling Short, Defect
Erato
Equal
Isis
Movement
The Ratio(logos) in Proportion (analogia)
REvolution
Distance
Impulse
Excess
The Thing with Another
Rhea(the wife of Kronos, but also “flow”)
Selene
Combination
That Which is To Be Endured; Misery, Distress
Boldness, Audacity(tolma)
Matter
Obstinacy
Nature
The Triad
Proportion(analogia)
Harmonia
Marriage
Knowledge(gnosis)
Peace
EVery Thing
Hecate
Good Counsel
Piety
The Mean Between Two Extremes
Oneness of Mind
The All
Perfection
Friendship
Purpose
The Tetrad
Nature of Change
Righteousness
Hercules
Holding the Key of Nature
The Pentad
Alteration
Immortal
Androgyny
Lack of Strife
Aphrodite
Boubastia(Egyptian divinity Boubastis)
Wedding
Marriage
Double
Manifesting Justice
Justice
Demigod
Nemesis
Pallas
Five-Fold
Forethought
Light
The Hexad
Resembling Justice
The Thunder-Stone
Amphitrite (Poseidon’s wife; a verbal pun: on both sides (amphis) three (trias)
Male-Female
Marriage
Finest of All
In Two Measures
Form of Forms
Peace
Far-Shooting(name of Apollo)
Thaleia
Kosmos
Possessing Wholeness
Cure-Ail(panacea)
Perfection
Three-Fold
Health
Reconciling
The Heptad
The Foreager(epithet of Athena)
Athena
Citadel(akropolis)
Reaper
Hard to Subdue Defence
Due Measure(kairos)
Virgin(parthenos)
Revered Seven (septas plus sebomai equals heptas)
Bringing to Completion (Telesphorus)
Fortune, Fate
Preserving
The Octad
Untimely Born
Steadfast
Seat or Abode
Euterpe
Cadmia
Mother
All Harmonious
The Ennead
Brother and Consort of Zeus
Helios
Absence of Strife
Far-Working(epithet of Apollo)
Hera
Hephaestus
Maiden(kore)
Of the Kouretes
Assimilation
Oneness of Mind
Horizon(because it limits the series of Memory units before returning to the Decad)
Crossing or Passage
Prometheus
Consort and Brother
Perfection
Bringing to Perfection(Telesphorus)
Terpsichore
Hyperion
Oceanus
The Decad
Eternity(aeon)
Untiring
Necessity
Atlas
Fate
Helios
God
Key-Holding
Kosmos
Strength
Memory
Ourania
Heaven
All
All Perfect
Faith
Phanes
Notes
- [Note: This quote comes from Plutarch, De Placitis Philosophorum, Liber 1, Chap. 3]Thomas Stanley, Ed. James Wasserman, J. Daniel Gunther, Pythagoras: His Life and Teachings (Ibis Press, May 1, 2010). Chapter 14.
- Huffman, Carl, “Pythagoreanism”, The Stanford Encyclopedia of Philosophy (Summer 2024 Edition), Edward N. Zalta & Uri Nodelman (eds.), URL = <https://plato.stanford.edu/archives/sum2024/entries/pythagoreanism/><https://plato.stanford.edu/entries/pythagoreanism/#math>
Bibliography
Note: The authors of the Pythagorean Sourcebook recommend Thomas Taylor’s Theoretic Arithmetic of the Pythagoreans and the section on number theory in Thomas Stanley’s Pythagoras. The Theology of Arithmetic Translated by Robin Waterfield, Phanes Press, Grand Rapids, 1988.
- Thomas Stanley. Ed. James Wasserman, J. Daniel Gunther. Pythagoras: His Life and Teachings. Ibis Press, May 1, 2010.
- Trans. Kenneth Sylvan Guthrie. The Pythagorean Sourcebook and Library. Phanes Press. July 1, 1987.
Photo Credits
- An ancient greek sage, with a beard and long hair, thin, and wearing a long white toga, sits on a rocky cliff in the Peloponnese, in ancient Greece in the 4th century BCE. Photo by Midjourney. Username: @david.k9
- A simple Athenian temple in the 5th century BCE. Photo by Midjourney. Username: @david.k9
David has studied traditional astrology since 2014. The Bay Area native completed Chris Brennan’s Introduction to Hellenistic Astrology course in 2015, and attended courses taught by Austin Coppock, Nina Gryphon, and Ryhan Butler. He is interested in exploring the less well known aspects of astrology, divination, and spirituality.