Mmmm, Pi . . . Let's see, where to begin. First off, Pi is an irrational number. Which means it can't be represented as a simple fraction. We all know it is represented by an endlessly non-repeating series of numbers to the right of the decimal point. In ancient Greece, the Pythagorean scholars discovered the first proof of irrational numbers by studying the sides of a pentagram. (The pentagram, as you most likely know, has represented everything from the 5 wounds of Jesus [nail through the right hand; nail through the left hand; nail through the right foot; nail through the left foot; and the spear driven through his side by Longinus] to having been associated with Freemasonry.) The pentagram is also utilized in the symbolism for neopagans and Satanists. To the Pythagorean scholars, the pentagram merely represented mathematical perfection, and served as a symbol of good health. The neopagans have circumscribed the pentagram and rendered it into the pentacle, representing the four elements + "spirit", the fifth indicated by the upwards point. Satanists, as you know, have inverted the pentagram and traditionally circumscribed it twice into the Sigil of Baphomet.
Pi is the ratio of a circle's circumference to its diameter. Pi is a real number. Real numbers are comprised of both rational and irrational numbers. Rational numbers are a countable set. Irrational numbers are not. Therefore, most real numbers are irrational. Natural numbers are the normal ones we're all familiar with, used for counting things. Since there's never been a universal agreement as to whether or not to include zero in the set of natural numbers, some say there are ten, while other's maintain there are only nine. Pi is a mathematical constant. A simple way of understanding Pi, is to realize that the circumference of any circle is a little more than three times as long as it's diameter, or 3.14159 etc. times as much. This remains a constant regardless of the size of a circle. Pi is also a transcendental number. Forget about understanding transcendental numbers, since almost all real and complex numbers are transcendental. Forget about understanding complex numbers as well.
We're here to try and understand Pi. One interesting fact is that it is impossible to "square a circle", that is, it is not possible to construct a square whose area is equal to the area of any given circle. That's kinda weird, if you think about it. About all I can add from my own observations, for whatever they may be worth, is the following input. Obviously with all the natural, real, rational, irrational, transcendental, and otherwise numbers being classified ad infinitum by the progression of mathematical science, we might infer that "enough is enough already", and suspect these classifications have gone way too far, thank you very much. It is for this reason I provide you here with the ultimate wisdom. And that is the fact that in reality, there is only one number. That would be the number one. Zero is not a number, for it merely represents the lack of numbers, the lack of value itself. Everyone already knows that any of the natural numbers we count with are merely multiplications of one. Ten equals ten ones, one million equals a million ones. Therefore, the entire set of natural numbers beginning with "two" and never ending, really exist for no reason other than to divide the whole. The reason for this has been lost in time. The wisest philosophers of old knew of this ultimate truth, that one is the onliest number. And it's because the wisest philosophers that ever existed knew perfectly well that all of creation is in fact a singularity. Think of it this way. The entire cosmos is a singular creation; therefore, numbers merely exist to divide it into parts, and to further divide the parts into smaller parts, ad infinitum.
We all saw Highlander when we were growing up. We all know perfectly well "there can be only One." This is no joke. Science has been exhausting itself by chasing the infinite tails of sacred division till Kingdom come, and for what purpose? Apparently to confound us all for no reason. The square root of infinity may as well be Pi. Because infinity is a circle. There is no such thing as nothing anymore. And that is because our entire existence, that of complete universal creation, has arrived here and now from negative existence itself. We may know nothing of negative existence; it is the great mystery which has confounded all the wisest men since time immemorial. We now dwell in static existence. We along with everything in creation are inexorably moving towards the inimitable light. That is all we can know of our state of being. Pi suffices as well as any symbol to represent that universal constant which remains unfathomable to us until this very day. Make of it what you will.