Plotinos: Complete Works, v. 3 In Chronological Order,...

Such then is "essential" Number (number that is "Being"). The other kind of number, which is called a number composed of digits, or "unities," is only an image of the former. The essential Number is contemplated in the intelligible forms, and assists in producing them; on the other hand, it exists primitively in essence, with essence, and before the essences. The latter find therein their foundation, source, root and principle.21 Indeed, Number is the principle of Essence, and rests in it, otherwise it would split up. On the contrary, the One does not rest upon essence; otherwise essence would be one before participating in the One; likewise, what participates in the decad would be the decad already before participating in the decad.