Pythagoras, the mystical mathematician, refined and built upon earlier understandings regarding the quality of vibration inherent in the nine numbers we ordinarily use simply for counting things.
Each number - one through nine - carries a vibration that has a certain meaning relating to the nature of the universe, and the nature of being in terms of the human expression. The sequence of the numbers follows a progression akin to growth, i.e. the development of an individual.
All these number/energies can be seen as carrying cosmic power into the manifest world. Each of us comes into the world on the wave of one of these energy/numbers. The day we are born represents a particular moment in cosmic terms, a particular and precise placement of the individual and our planet in the energetic field of manifestation. And thus, as in the science of Astrology, the individual has an energy signature, so to speak. And this energy signature represents the predominate manner in which an individual will be expressing during the life of the person.
Since there are only nine numbers out of which we express our birth-given creative energy, one might assume there are only nine human types running around on the planet. But this is not the case; for it is in our names where we find clues to our personality structures and our soul purposes.
The art and science of numerology makes use of the letters in our names to pin point the subtleties of our individual vibration frequencies. Each letter of the alphabet is assigned a corresponding vibration.
By converting the letters to numbers, we can begin to build a picture of an individual's mind-body-spirit profile. At this point, the Doubting Thomas in you might be questioning how one's name can provide so-called cosmic information [that is information coming from the Cosmic Mind of All Knowing] regarding an individual's mind-body-spirit profile. Whereas one's time of birth may seem less arbitrary, and thus understandable as something fated or destined, one's name, usually given by parents, seems to be rather somewhat arbitrary, or at least under the direct influence of the parents rather than a formulation having come from some higher source, such as one's Soul.
Numerology responds to this kind of questioning in various ways.
1. In most cases, parents generally consider it quite a serious matter when it comes to giving their child its name. They ponder deeply, listen to inner promptings, their dreams. They will consult other family members. Even when there is a desire to name the coming child after an older or deceased family member, the parents take into consideration many subtle thoughts and feelings. Even if the name giving comes out of some spontaneous inclination, such as naming the child after a favorite singer or movie star, or even a president of the country, or famous historical figure, such promptings, when looked into deeply, usually indicate an amount of intuitive activity happening within the psyche of the parent or parents. Therefore, it can be said that the name giving activity strives to impart in the new life a sense of its role in life or of its destiny.
2. In esoteric terms, it is said that the souls of the parents and the soul of the newborn, along with guides and teachers, have already formulated their life plans in the in-between stage, or life dimension of their soul existences. Thus the child's name along with the energy patterns the name represents has already been established before any of the souls involved have entered their physical existences.
3. And finally, one must consider the fact that a name, when spoken, carries an energy vibration in its most subtle form. And this sound imparts a subtle, intuitively understood message. The child, from infancy on, hears this vibratory message constantly. The parents murmur the name over and over. Eventually that energy pattern becomes imprinted into the child's sub-conscious mind. The parents have chosen the name as a consequence of deep intuitive urgings, no matter how superficial or flippant that choice may seem on the surface of things. The soul of the child has already made agreements with the souls of the parents, along with the help of spirit guides and teachers. The child is prepared to receive the subtle vibratory message that comes across when hearing its name spoken. And thus, the sub-conscious mind of the individual from childhood on is developing a hidden sense of the cosmic message for its Life Purpose, its Life's Goals - the reasons for its coming into the physical plane to express and learn and grow in a certain and precise way for the benefit of its Soul's Growth and Healing.