On Nicomachus's Introduction to Arithmetic

because it is found to be prior and more primordial. It destroys the others along with itself, and in turn, it is carried along with them. Things that destroy others but are not destroyed by them, or conversely, are carried along with others but do not carry them, are shown to be prior and older in a certain way. Therefore, a consideration of the primary technology—arithmetic—would be most reasonable and fitting.

Now, as for quantity, which is number, Thales defined it as a system of units (according to the Egyptian preference, where he also pursued his studies). The arithmetic original: "ἓν ἰδίων" unit/one will not fall under either the unit or the things in the definitions. Pythagoras defined it as the extension and activity of the seminal logoi rational principles/proportions within the monad, or otherwise as that which subsists before all things in the divine intellect, from which and out of which all things are ordered and remain numbered in an indissoluble arrangement. Others among his followers call it the progression from the monad to its magnitude. Eudoxus the Pythagorean said: "Number is a limited multitude," distinguishing species and genus, just as quantity was distinguished in the preceding section. The akousmatikoi auditory pupils/listeners around Hippasus said that number is the first paradigm of the creation of the cosmos, and in turn, the critical instrument of the cosmogenic god. Philolaus says that number is the ruling and self-begotten cohesion of the eternal persistence of cosmic things.