In the course of history there are more references – more or less explicit – to a Tenth Planet orbiting around our Solar System, other than the Enuma Elish and the Sumerian chants.

According to Aristotle, for instance, the Pythagoreans with their studies on numbers had a mathematical idea of the Universe very similar to the Egyptian and the Mesopotamian civilizations (the more so if we consider that Pythagoras learnt much of his wide esoteric knowledge first in Egypt, and then in Babylonia.):

"...The Italian philosophers known as Pythagoreans take the contrary view. At the center, they say, is fire, and the earth is one of the stars, creating night and day by its circular motion about the center. They further construct another earth in opposition to ours to which they give the name counterearth ..." [Aristotle, De Coelo]

"…The so-called Pythagoreans give two explanations...Some say that the Milky Way is the path taken by one of the stars at the time of the legendary fall of goreans, Phaethon..." [Aristotle, Meteorologica]

"… Since the decade seems to be a thing that is perfect, and to have comprised the entire nature of numbers, hence they [the Pythagoreans] also assert that the bodies that are borne through the heaven are truly ten in  number; and whereas nine only are apparent, on this account  they constitute the confronting earth tenth..." [Aristotle, Metafisica]

These three passages offer clear references to the past and the present situation of a Planet X which exists in our Solar System, although not always visible: the counterearth in the De Coelo, a "star" or planet in opposition to ours. The implication of the counterearth with Marduk and Tiamat's clash, as told in the Sumerian's Enuma Elish, is something that should not be ignored.
In the Meteorologica we find a reference of a planetary collapse, of a catastrophe which involved "one of the stars" which, in ancient times, passed through the Milky Way. Now, if "...the earth is one of the stars..."[De coelo], we can reasonably sustain that the phrase refers to one of the planets. And the fact that the Pythagoreans believed that that planet-star once passed through the Milky Way, it's only logical to think that such planet belonged to our Solar System (a Tenth Planet, then) and had suffered a tragic destiny at the time of Phaethon (Phaethon is a mythological character; son of Apollo and Climene. According to the myth, Phaethon didn't believe to be the son of a god and, to prove that, he demanded to lead the chariot of Apollo. Being inexperienced, he led the chariot onto an unknown path. This deviation damaged the earth and produced a burn in the Milky Way. Zeus killed Phaethon striking him with a lightning. Phaethon fell into the Eridanus River, today known as the Po River, in Italy.)

A lot could be said about the fascinating esoteric symbolism of the Pythagoreans in connection with the myth of Phaethon, but this is not the purpose of this study.
In the Metafisica we have a clear description of our complete Solar System as it was known by the Mesopotamic populations before the Greek: the planets must be ten because, according to the Pythagoreans, the number ten “...seems to be a thing that is perfect, and to have comprised the entire nature of numbers...”; and if “...the number contains all other things...” [Strobaeus, Eclogae Physicae], the syllogism identifies the number ten as the only number of perfection.
Since the planets in the sky are nine, the Pythagoreans place the counterearth as the “Tenth Planet”.

Considering the contribution Pythagoras and his school gave to Mathematics, Geometry, Goniometry, Astronomy, Numerology, Arithmogeometry, Philosophy, Music, Cosmology – and, only to name a few discoveries: the Multiplication Tables, the Pythagorean Theorem, the evolution of the concept of number, the dissemination of the Litmus Test, the calculus upon the harmonic vibrations, the immeasurability and irrationality of some quantities, the properties of triangles, hyperboles and ellipses, the dodecahedron inscribed within a sphere – such contributions laid the foundation upon which the whole Western culture stands. Therefore, is it not utterly improbable, if not radically illogical, that "that man" (as he was known among his disciples), didn't frame the structure of our Solar System correctly?
It seems to be more simple to treasure such a revelation, and take from here to improve our mindset, so to better understand all which surrounds our existence.

	NAGAS: A Shapeshifting History
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