Numerology
“”Three.... is a magic number.

—Schoolhouse Rock (& later De La Soul) 
Uhoh, it's 
Trying to make a devil out of me 
Style over substance 
Popular pseudosciences 
Random examples 
Numerology is the study of, or belief in, the meaning of various numbers associated with people or events. There are many specific forms that numerology can take. Some try to convert letters to numbers and add them up, others try to assign properties and descriptions to each "number."
Contents 
[edit] Importance of numbers
“”The numbers, Mason... What do they mean?!

It is important to think a little bit about numbers and the meaning of cardinality (although a thorough treatment of this is not needed). Numbers in western languages are written in base ten  that is, when we run out of fingers to represent a number, we reuse them, wrapping around, as it were, adding another digit place to represent the next jump.
It is apparent that the whole "theory" hinges on this relatively arbitrary choice of base, which probably stems from humans having five digits on each of two hands. Insect numerology, for instance, could yield very different answers — we can conjecture that intelligent insects may evolve a system of numbers in base 6. Computers use only base 2, being only able to process states as either "on" (1) or "off" (0). The universe, however, doesn't deal with numbers like this — if it even deals with numbers at all — just like it doesn't deal with a discrete concept of "species". As a result, numbers, when considered like this, are quite arbitrary and easily manipulated to indicate anything you like. A famous example is the absurd conclusion to the quest for the ultimate question in Hitchhiker's Guide to the Galaxy where the answer was 42 and the question turned out to be "What do you get if you multiply six by nine?" — it was pointed out that 6 times 9 does in fact equal 42... in base 13.
Another functional absurdity of trying to assign meaning to numbers comes from playing with the numbers or digits in dates. Dates are also utterly arbitrary human constructions. The year "0" as defined in the CE/BCE system is technically just an arbitrary point, although it just so happens to coincide with a more traditional system. The arbitrary factors of dates also include when we choose to make up for the discrepancies in the length of the year relative to exact numbers of days in a year (leap days, minutes, seconds, etc.).
Basically, numerology's "value" consists of the incredible woo experienced by people when shown that the number of letters in their names, when manipulated, show how important they are in the universal scheme of things.
Richard C. Hoagland often uses numerology in his attempts to prove that the Face on Mars is not natural. To him, the magic numbers are 19.5 and the sin of 19.5°, 0.333 (although by conventional rounding, sin(19.5) is actually 0.334. Hoagland is not known for accuracy.)
Some well known mathematicians have been interested in numerology, Plato called the study of number symbolism "the highest level of knowledge" while Pythagoras believed numbers had souls as well as magical powers.^{[1]}
[edit] Numerology in Hebrew culture
A quick glance at the Bible shows that numbers mattered to to the Hebrews. It is not coincidence that there were 7 days of creation, as 7 is the holy 3 and the holy 4 combined.^{[2]}
"40" is a number that means "a really long time," and a "whole lot of something," in the way that someone might generically say "hundreds" today. 40 days and 40 nights tells a reader, "Man, that rain just went on and on." Killing the 40 children who teased Isaiah is again a repetition of this holy number 40. Though it does not occur as often, 120 has the same (though bigger, as it's three 40s) sense of "uncountable big."
Most scholars do not think the use of these numbers in any biblical text was ever meant to be a counted amount of days. 12 is another sacred number, though it shows up in the Greekinfluenced writings of 200 BCE to 1 BCE and into the early Christian writings far more often. Scholars do not think that "12 disciples" means there were actually 12 human dudes with names and birthdays running around with Jesus, but there were "a few," and saying 12 adds mojo.
Ironically, despite there being 10 fingers, and 13 moons, the Jewish calendar has 12 months. Something recreated when the Greek calendar was tossed in favor of the Gregorian one.
[edit] Numerology in Christianity
“”For St. Augustine, numbers had to have come from God, for they obey no laws humans could devise.^{[3]}

St. Augustine wrote pages on the Godliness of numbers. Seven, he believed, was so sacred it "represented the entire universe" and "embraced all created things." Ten, to Augustine, was 7 plus the "three aspects of the Holy Trinity."
[edit] Gematria
Gematria is the Kabbalistic study of Hebrew words by assigning every letter in the alphabet a numerical value (increasing by 1 until 10, increasing by 10 until 100, and increasing by 100 until 900). For example, Chai, the Hebrew word for life, is spelled chetyod, giving it a gematria value of 18. However, the gematria of words is often purely coincidental, and can be used to prove nearly any point (including how the "pi mistake" isn't really a mistake).
[edit] Numerology in other ancient cultures
[edit] The Egyptians
The Eye of Horus is not only a depiction of the god Horus (oudjat), but it was also a precise layout of the ratio of rational numbers, as 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64.
[edit] The Chinese
The Chinese have an entire system of fortunetelling based on numbers, the I Ching. Not only did each number have a specific meaning, (for example, the number 1 was symbolic of beginnings), the experts used "complex"^{[4]} formulae to make triads of numbers that calculated actions an emperor should take, partnerships he should make, etc.
[edit] Readings that will stun you with their honesty
This site promises "readings that will stun you with their honesty," but they've been rumoured to give the same reading to everyone,^{[5]} or give nothing at all. They're also here with different page layout.
[edit] See also
 Pseudoscience
 Bible code
 666
 Harold Camping
 The Incredible Dr. Matrix: The World's Greatest Numerologist by Martin Gardner. A mathematician looks at numerology.
[edit] Footnotes
 ↑ http://www.independent.co.uk/lifestyle/history/42theanswertolifetheuniverseandeverything2205734.html
 ↑ I've been told in Religious Studies classes that 12 is sacred for the same reason, 3 times 4. There is nothing to back that up but the urban legends of many professors who all take it as sacred truth
 ↑ Mathematician, du Sautoy, The Code. The quote shows that the God of the Gaps lives in math as well as science.
 ↑ by complex, I mean several steps, not the extremely complex formulas of today's maths
 ↑ http://www.ripoffreport.com/reports/0/273/RipOff0273036.htm