A little background
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The geometrical symbol has been used in several forms throughout history beginning in 3000 BC, until it was eventually associated with satan and leviathon (The great mythical serpent deity/demon) sometime in the 20th century.
The religious use of this shape, and its subsequent defiling by wester patriachal religion, is very important to
re-establishing our links to nature and its mathematically inspired roots. The pentagram is currently used in neo-pagan and wicca as a symbol of the Great Horned Goddess (the essence of life) and she was worshipped in conjunction with the seasons and the fruit of nature. This Goddess worship embodied the concepts of male/female duality in the horns, but I digress as there are many other sites dedicated to the Goddess. The important point is the symbol was used to represent the flowers blooming, the fruit ripening, our childrens birth and of general Health and Happiness. A similar motif is found in mans first artistic pottery - the statues of Venus (the Goddess).
Pythagoreans
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The Pythagorean era came about from the discovery of mathematical concepts within nature, and the relationship between nature and geometry. They thought the Universe was built on nice whole integers, but they were in for a shock with the discovery of irrational numbers like Pi (3.14...) and the Golden Ratio (1.618...)
The work done by the Pythagoreans within the field of mathematics has resonated throughout humanity, but not many know their biggest secret was these irrational numbers. To protect the secret they would put 'loose tongued' colleagues to death. <b>To enter their secret society you had to be capable of drawing a perfect pentagon containing a pentagram.</b> But why this symbol?
The actual form itself is created by simply joining each of the 5 points of a pentagon to every other point, a mirroring of lifes own tendency to form groups and relationships. The pentagram is created containing a new inverted pentagon, which means the process can continue on forever and ever and ever...Amen
One of their most important geometrical discoveries was the Golden Ratio (Phi). They believed it represented some natural force of beauty in the natural world. This ratio is absolutely embodied within the pentagram, as the following image highlights:

Red/Green = Green/Blue = Blue/Magenta = Phi
The ancients were all philosophers, thats what happens when your minds bored
Fibonacci, Hindu and Buddhism
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There is another mathematical method that reached western minds 100 years after was first discovered from Indian Holy men (Religious mathematicians). The famous Fibonacci sequence shown to the mainstream cinema goers in the DaVinci code. The sequence is simple - the sum of the last two sequence numbers: 1, 1, 2, 3, 5, 8, 13, 21, 34 etc. The divine thing about these numbers is they too embody the Golden Ratio (Phi, 1.618...). If you take a number in the sequence and divide it by the previous number, you get a loose approximation to the magical Phi ratio 1.618. The higher you go in the sequence (eg. 89/55 = 1.61818188), the more closely you approximate Phi!
The numbers can also be laid out geometrically to form a familiar spiral:

Hindus believe the first incarnation of Vishnu (Mother Earth) was in the form of an ammonite (spiral shaped fossils), and they rever these fossils so much they won't touch them unless they have been ritually cleansed. Obviously the nature of the spiral was understood in its entirety in earlier history. The internal angles derived from a pentagon are 36, 72 and 108. The number 108 is especially revered in India and China, with a bell being rung 108 times at new year, chanting mantras 108 times, saying prayer to the sun 108 times, the mala bracelets having 108 beads (often separated into 3 sections). Even the TV series lost has a significant part of mythology based on Eastern thoughts, the I-Ching is alluded to in the Dharma initiative symbol, and the countdown timer in the research laboratory has to be reset every 108 minutes. Its only a hook into cultural and mystical beliefs, but the reason its a hook at all is important.
Yet there is not a single piece of literature that can definately say why 108 is special. I believe it all relates back to the Pentagon and the Pentagram embodying Phi.
Where spiralling and diamond patterns in nature are observered, they are often (too often to discount) created from two opposing spirals, and these spirals are have a preference to two sequential Fibonacci numbers. Look for sunflower and phi/golden ratio/spirals (having problems linking).
To show how fractal our world really is, check out this cousin of cauli and broccoli (http://www.fourmilab.ch/images/Romanesco/):

QUOTE(wiki)
The greatest misconception in the mystification of the golden spiral is the incorrect assumption that all spirals in nature are in fact the golden spiral. While logarithmic spirals are often observed, they may be of differing pitches, and therefore there is no single "spira mirabilis".
Of course the above pessimistic approach is the best method of staying objective, but there is enough evidence around to take on the old conceptions of religion and really see the Universe is based numbers that re-occur on all levels.Its important to state that the Pentagram, the eastern religious revering of 108, and the ancient Goddess Worship in the statues of Venus and all other identities (Isis, Mary, Aphrodite), are all related to this natural phenomenon.
Below shows the naturally formed path of Venus in our nights sky. As we orbit 8 times round the sun, the planet Venus (The morning star, Lucifer), orbits 13 times. Those are two sequential numbers in the Fibonacci sequence, and whenever that happens you are dealing with something that really is Divine.

This early spiritual belief in mathematics has been ignored and untrusted, but it has more relevance to ANYTHING any religious book can state. Its there right in front of our eyes, and its tangible. Even now many scientists and philosophers alike are talking about fractal realities and the nature of numbers. It seems like we've been deluded and misdirected from the true source of religion - experience.
This is why I believe in the Supernatural and Occult emblem - the Pentagram.
I'd love to discuss peoples feelings, comments and criticisms.
