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Gradus ad Parnassum

The Greek astronomer Aristarchus of Samos [310-230 BC] knew that the Earth orbits the Sun and determined the distance between them. The chief librarian at the Library of Alexandria, another Greek by the name of Eratosthenes of Cyrene [276-195 BC], measured the circumference of the Earth.

If this was the case, how did ancient philosophers all over the world (even in Greece!) come to think that Earth was the center of the Universe ["geocentric model"]? Or that the Earth's shape was a disk / square ["flat Earth"]? I don't think that any of the people who first created these models (sometime way before recorded history) intended for us to see them as literal, but they do have a very important function. To explain...

If we were near the ocean and looked out at the horizon, we could see that the mast of a ship appears before the hull when it is coming towards us. This shows us that the Earth is curved. However, if there was no ship, it might be hard to tell. Anywhere we stand on the surface of the Earth, it seems as if we are standing on a flat plane. This is because the size of the sphere that we are standing on is massive! So we naturally speak of "down" and "up" rather than "in" and "out". [If we want to be extra fancy, mathematically we could say that the surface of the Earth is "a sphere at infinity", and anywhere we stand upon it is "locally flat".]

Now, if we look out at the stars, we come to find that their positions relative to one another never seem to change. In other words, a constellation is always in the same position in the sky when comparing it to other constellations. Therefore, we can think of the sky as a dome with the stars projected on it. [They still do something like this in astronomy; it is called the "celestial sphere". It is also the reason why observatories and planetariums are domed.]

We can symbolize "Heaven" as a dome (or as a circle for the edge of this dome), resting on "Earth" as a square (for how its surface seems flat and for the fact that there are four compass directions). The observer seems to be at the center of everything! This is where these models come from.

[There is also a well-known method in geometry called "squaring the circle" where we try to make a circle and a square take up the same amount of space (i.e.: give them the same area). This allows us to make an architectural structure called a "pendentive", which is a circular dome resting over a square foundation.


Photo Credit: Dr. William Long

Notice how prevalent these types of structures are within buildings like cathedrals! Many sacred sites also seem to double as observatories. In general, "squaring the circle" is symbolic of "uniting Heaven and Earth".]

Let's take it a step further...We will symbolize the constellations as various kinds of people, animals, and objects. Then, we will come up with fantastical stories about them in order to make all of the knowledge that we have gathered from mapping out the sky over many generations easy to transmit orally. Is this where much of mythology of humanity comes from?

[A cursory glance at the mythology of the Greeks shows us that it does not seem like it is to be taken literally, but was representative of something...the question is, what? A lot of sacred knowledge was passed down through oral traditions that were only written down as holy scriptures long after they first appeared. Methods of memorizing vast quantaties of information are generally referred to as "the art of memory" and they have been used for a long time (since at least ~500 BC). The Greeks used a system called the "method of loci" that works by associating the information to be memorized with a particular location within a familiar scene. Walking through this scene within one's imagination allows one to recall the information easily.]

If we observe the sky long enough, we will come to find that some "stars" seem to move relatively quickly across the "background of fixed stars" (i.e.: the dome of the sky). In other words, there are star-like lights that seem to move across the constellations. These are planets. The term "planet" is derived from a Greek phrase, "asteres planetai", which literally means "wandering star". Therefore, it originally included both the sun and the moon!

[This distinction is still acknowledged within astrology. For example, a "natal chart" shows where these "planets" (including the sun and moon) seem to be in the sky at the time and location of our birth. While it may not seem like it nowadays, astrology and astronomy are not separate fields. They have a common root and they both continuously verify one another, as do science and spirituality in general when they are brought into balance.]

The "planets" that are visible to the naked eye from the surface of the Earth are:

The Sun, The Moon, Mercury, Venus, Mars, Jupiter, and Saturn

They are ordered by the how fast they seem to move across the sky. This is where the seven days of the week come from. Some of the names associated with them in English still have an obvious connection to planets, like Sunday, Monday (or "Moon" day), and Saturday (or "Saturn" day). The others are derived from the Old English names of deities within Germanic "paganism":

• "Tuesday" = "Tiw's day", a Norse god of combat, similar to the god "Mars" of the Romans
• "Wednesday" = "Woden's day"; "Woden", more commonly known as "Odin", has a connection to "Mercury"
• "Thursday" = "Thor's day", which corresponds to "Jupiter"
• "Friday" = "Frige's day", which corresponds to "Venus"