One, the Number That Is Barely a Number

One is the beginning and, in much ancient thought, not really a number at all but the source of number, the monad, the undivided unity from which the counting numbers proceed. The Greeks debated whether one was a number or the principle behind number, since a number was understood as a multitude of units and one is not a multitude; it was often set apart as the origin of the even and the odd alike. From this comes its symbolism of unity, origin, the self and the singular, the point before extension, the source, the first cause, and in monotheistic thought the oneness of God.

In modern numerology one is the number of the individual, of leadership, independence, initiative and the pioneering will, the self asserting itself. That character reading is not ancient: it belongs to the digit-reduction system assembled in the United States around 1900, principally by L. Dow Balliett, and habitually called Pythagorean though nothing like it is attested for Pythagoras. The arithmetic of one is old; its personality is about a century and a quarter old.