Aristotle's treatise on "first philosophy" (c. 350 BCE) is, for this corpus, the
single most important *external witness* to early number-mysticism — precisely
because Aristotle is a hostile, sober reporter. Book A (I) preserves the earliest
reliable evidence for what "the so-called Pythagoreans" actually taught (that the
principles of number are the principles of things), for the Pythagorean table of
ten opposites, for the doctrine that made the heavenly bodies ten (with the
invented counter-earth), and for Plato's "unwritten" first principles, the One and
the Indefinite Dyad. Almost every Pythagorean/Platonic number-claim elsewhere in
the corpus should be checked against this text, which reports the doctrines while
declining to endorse them.

Augustine of Hippo's *City of God* (413–426 CE) is a vast work of Christian philosophy
of history; it enters this corpus for one famous chapter (XI.30) that gives the
sharpest patristic statement of number-symbolism grounded in real mathematics. Augustine
argues that God completed creation in six days because six is a *perfect number* (equal
to the sum of its divisors 1+2+3) — and, crucially, that six's perfection is prior to
and independent of the six days, so that the arithmetic explains the theology rather
than the reverse. It is a model of the corpus's ideal: a sacred-number claim resting on
a genuine property, with the logic made explicit.

The oldest of the Indian *Śulba Sūtras* (c. 800 BCE) — ritual manuals, appended
to the Śrauta Sūtras of the Taittirīya (Black Yajurveda) school, giving the
geometric rules for laying out Vedic fire-altars with cord (*śulba* = "cord,
rope") and pegs. It is a landmark for this corpus because sacred mathematics here
is literally *ritual practice*: to build an altar of prescribed shape and area you
must square rectangles, double squares, and combine areas. In doing so the text
states the "Pythagorean" area-relation in full generality (c. two–three centuries
before Pythagoras), records Pythagorean triples, and gives a remarkably accurate
value for √2. It is the strongest single witness to the thesis "geometry born of
the altar."

The *Corpus Hermeticum* is the core collection of Greek philosophical-religious
treatises (2nd–3rd c. CE, Greco-Egyptian) ascribed to the legendary Hermes
Trismegistus. It is the founding text of the Hermetic tradition and the source of
its cosmology of ascent: in the first treatise, *Poimandres*, the soul rises through
the seven planetary "governors," shedding their influences, to the Ogdoad (the eighth
sphere) and beyond. It supplies the corpus's Hermetic number-symbolism (the seven
spheres + the eighth) and much of the "as above, so below" worldview — though the
famous maxim itself belongs to the later *Emerald Tablet*, not to this Greek corpus.
Its dating is a landmark in the history of scholarship: Casaubon (1614) proved it
Roman-era, not primordial Egyptian.

The foundational treatise of Greek deductive geometry (c. 300 BCE), thirteen
books proceeding from definitions, postulates and common notions to increasingly
elaborate constructions. It matters to this corpus for three reasons: (1) its very
first proposition builds an equilateral triangle from two equal circles — the
construction that generates the *vesica piscis*; (2) Book VI defines the division
of a line "in extreme and mean ratio" (the so-called golden ratio); and (3) Book
XIII constructs the five regular ("Platonic") solids and proves that exactly five
exist. Because it is rigorous rather than mystical, the *Elements* is the
discipline anchor against which "sacred geometry" claims should be checked — most
of them borrow Euclid's figures and add meanings Euclid never states.

Herodotus of Halicarnassus (c. 484 – c. 425 BCE), "the Father of History," devotes
Book II of his *Histories* to Egypt. For this corpus it is the **earliest surviving
description of the Giza pyramids** and a key witness to how the Greeks read Egypt as
the homeland of geometry and sacred measure — while also being the origin of several
durable *mismeasurements* that later numerologists have mined. The node records
Herodotus as the oldest textual attestation for the site, with an explicit caution:
he wrote roughly two thousand years after the pyramids were built and reports
hearsay, so he is a source for *reception*, not metrology.

*On the Pythagorean Life* (Περὶ τοῦ Πυθαγορικοῦ βίου) is the opening book of
Iamblichus' ten-volume *On Pythagoreanism* (early 4th c. CE) and, with Porphyry's
*Life*, the fullest surviving account of Pythagoras and his school. It is the principal
source of the tetraktys oath ("by him who gave to our soul the tetraktys") and of most
of the doctrines, miracles and rules popularly attributed to the Pythagoreans. For this
corpus it is indispensable *and* treacherous: the richest reservoir of Pythagorean
number-lore, written some eight centuries after Pythagoras and shaped by Neoplatonic
piety, so nearly everything in it must be dated to late antiquity, not to the sixth
century BCE.

Johannes Kepler's two great works of geometric cosmology — the *Mysterium
Cosmographicum* (1596) and the *Harmonices Mundi* (1619) — are the early-modern
culmination of the Pythagorean–Platonic dream that the cosmos is built on number and
figure. The *Mysterium* proposed that the five Platonic solids fix the spacing of the
six planetary orbits; the *Harmonices* sought the literal "music of the spheres" in the
planets' motions. Both projects are, in their sacred-geometric ambition, failures — yet
the second contains Kepler's third law of planetary motion. This node captures the exact
moment sacred geometry became testable science and was, in part, superseded by it.

The *Introduction to Arithmetic* (Ἀριθμητικὴ εἰσαγωγή, c. 100 CE) of Nicomachus of
Gerasa is the founding text of Neopythagorean number-philosophy and was the standard
arithmetic primer for more than a thousand years. It matters to this corpus because
it is the bridge between real number theory and number-mysticism: it gives the
classification of numbers (odd/even, prime, figurate), the doctrine of the four
"perfect" numbers (6, 28, 496, 8128), and the arithmological reading of the monad
and dyad as the principles of all number — treating arithmetic as the key to the
cosmos. Much of the corpus's "sacred number" material descends, directly or through
Boethius' Latin adaptation, from this book.

Philo of Alexandria's treatise *On the Creation of the World according to Moses*
(c. 30 CE) reads the six-day creation of Genesis through Greek — chiefly Pythagorean
and Platonic — number-philosophy. It is the corpus's single richest ancient source
for the *arithmology of small numbers*: the long hymn to the hebdomad (seven) that
the `number-7` and `concept-seven` nodes already cite, and the argument that God
ordered the cosmos in six days *because six is the first perfect number*. This node
gives those already-cited passages their own text_source home and closes the
author-edge from `person-philo`.

Plato's late cosmological dialogue (c. 360 BCE) in which the craftsman-god
(*dēmiourgos*) fashions the cosmos as a living being on a mathematical pattern.
It is the single most important classical source for the idea that the physical
world is built out of number, ratio and geometric form: the four elements are
bound into a continued geometric proportion; the World-Soul is divided according
to musical ratios; and the elements themselves are assigned to four of the five
regular ("Platonic") solids, with the dodecahedron reserved for the whole. Almost
every later "sacred geometry" and "harmony of the spheres" tradition traces back,
directly or through Neoplatonism, to this text.

The *Enneads* are the collected treatises of Plotinus (c. 204–270 CE), edited after
his death by his pupil Porphyry into six sets of nine (hence *ennea*, "nine"). They
are the founding text of Neoplatonism and the source of the most influential
metaphysics of unity in the Western tradition: the One, beyond being and beyond
number, from which Intellect and Soul emanate. For this corpus the *Enneads* anchor
the crucial distinction between the *metaphysical* One and the *arithmetical* one, and
they supply the philosophical frame in which later Neoplatonists (Iamblichus, Proclus)
made geometry a spiritual ascent.

A treatise (c. 100 CE) in Plutarch's *Moralia*, addressed to the priestess
Clea, interpreting the Egyptian Isis–Osiris–Horus myth through a Middle-Platonic
and Pythagorean lens. It is the classic ancient text that reads a myth as encoded
mathematics: in chapter 56 Plutarch identifies the 3-4-5 right triangle — "the
most beautiful of the triangles" — with the divine family, making Osiris the
upright (3), Isis the base (4), and Horus the hypotenuse (5). The passage is the
single most-cited bridge between Egyptian theology, the Pythagorean theorem, and
the "generative" reading of number, and it is a hub node linking the numbers 3, 4
and 5 to the Egyptian tradition and to Plato's number-lore.

The *Commentary on the First Book of Euclid's Elements* by the Neoplatonist Proclus
(412–485 CE) is at once the principal ancient source for the *history* of Greek
geometry (its "catalogue of geometers" preserves what little we know of Thales,
Pythagoras, Theaetetus, Eudoxus and Euclid) and the classic statement of the
*Platonising* reading of mathematics — that geometry mirrors the eternal Forms and
that the whole of Euclid's *Elements* is oriented toward the construction of the five
"cosmic figures." For this corpus it is doubly useful: a genuine historical source
that must nonetheless be handled critically, because it writes 700+ years after
Euclid and frames everything through Neoplatonic metaphysics.

The oldest of the four Vedas and one of the oldest surviving religious texts of
any Indo-European language — 1,028 hymns (*sūktas*) in ten books (*maṇḍalas*),
whose core "Family Books" (2–7) date to c. 1500–1200 BCE and were transmitted
orally with extraordinary fidelity for millennia. It enters this corpus as the
fountainhead of Vedic number-symbolism: the syllable-counted metres that make
sacred speech itself numerical; the "riddle hymn" of Dīrghatamas (1.164) with its
twelve-spoked, 360-pegged wheel of the year; the cosmic dismemberment of the
Puruṣa (10.90); and the recurring sevens (the Saptarṣi, the seven priests, the
seven rivers) that the concept-seven node already reaches toward. It is also the
tradition whose ritual the Baudhāyana Śulba Sūtra geometry serves.

The *Sefer Yetzirah* ("Book of Formation/Creation") is the earliest and most concise
work of Jewish esoteric cosmology, describing the creation of the world through the
"thirty-two paths of wisdom" — the ten *sefirot* (numerical emanations) and the
twenty-two letters of the Hebrew alphabet. It is the textual root of the Kabbalistic
Tree of Life and the source, for this corpus, of the sacred decad of the sefirot
(cited in `number-10` and `symbol-tree-of-life`) and of a thoroughgoing letter-and-
number cosmology. Its dating is genuinely uncertain, which the node keeps explicit.

The *Emerald Tablet* is a short, cryptic Hermetic text that is the source of the single
most quoted esoteric maxim — "that which is above is as that which is below" — the
canonical statement of the correspondence between macrocosm and microcosm. Ascribed to
the legendary Hermes Trismegistus, it is in fact an **early-medieval Arabic** composition,
first attested within the *Sirr al-Khalīqa* ("Secret of Creation") and only later
rendered into Latin, where it became foundational to Western alchemy. This node exists to
give the "as above, so below" principle its correct textual home — and to keep it firmly
distinct from the older Greek *Corpus Hermeticum*, which does not contain it.

The only architectural treatise to survive from classical antiquity, written
c. 30–15 BCE by the Roman architect-engineer Vitruvius and dedicated to the
emperor Augustus. Book III opens with the doctrine that a temple's proportions
(*symmetria*) must derive from the proportions of the well-formed human body —
which fits both a circle centred on the navel and a square (the *homo ad circulum
et quadratum*, the direct source of Leonardo's "Vitruvian Man"). The same chapter
transmits Greek arithmology: six and ten are "perfect numbers," combined into
sixteen. It is the canonical text linking the human body, number, and sacred
architecture, and the reason the microcosm–macrocosm idea entered Renaissance
design.