Numerology is any of many systems, traditions or beliefs in a mystical or esoteric relationship between numbers and physical objects or living things.
Numerology and numerological divination were popular among early mathematicians, such as Pythagoras, but are no longer considered part of mathematics and are regarded as pseudomathematics by modern scientists. This is similar to the historical development of astrology out of astronomy, and alchemy from chemistry. Today, numerology is often not associated with numbers, but with the occult, alongside astrology and similar divinatory arts.
The term can also be used for those who, in the view of some observers, place excess faith in numerical patterns, even if those people don’t practice traditional numerology. For example, in his 1997 book Numerology: Or What Pythagoras Wrought, mathematician Underwood Dudley uses the term to discuss practitioners of the Elliott wave principle of stock market analysis.
Many alchemical theories were closely related to numerology. Persian alchemist Jabir ibn Hayyan, inventor of many chemical processes still used today, framed his experiments in an elaborate numerology based on the names of substances in the Arabic language.
Scientific theories are sometimes labeled numerology if their primary inspiration appears to be mathematical rather than scientific. This colloquial use of the term is quite common within the scientific community and it is mostly used to dismiss a theory as questionable science.
The best known example of numerology in science involves the coincidental resemblance of certain large numbers that intrigued such eminent men as mathematical physicist Paul Dirac, mathematician Hermann Weyl and astronomer Arthur Stanley Eddington. These numerical co-incidences refer to such quantities as the ratio of the age of the universe to the atomic unit of time, the number of electrons in the universe, and the difference in strengths between gravity and the electric force for the electron and proton.
Large number co-incidences continue to fascinate many mathematical physicists. For instance, James G. Gilson has constructed a “Quantum Theory of Gravity” based loosely on Dirac’s large number hypothesis. Wolfgang Pauli was also fascinated by the appearance of certain numbers, including 137, in physics.
Numerology is a popular plot device in fiction. It can range from a casual item for comic effect, such as in an episode titled The Seance of the 1950s TV sitcom I Love Lucy, where Lucy dabbles in numerology, to a central element of the storyline, such as the movie Pi, in which the protagonist meets a numerologist searching for hidden numerical patterns in the Torah.
There are no set definitions for the meaning of specific digits. However, common examples include:
0. Everything or absoluteness. All
1. Individual. Aggressor. Yang.
2. Balance. Union. Receptive. Yin.
3. Communication/interaction. Neutrality.
5. Action. Restlessness.
6. Reaction/flux. Responsibility.
9. Highest level of change.