Succession or repetition gives us Number dyad, TRIAD, etc. and the extent traversed is a matter of Magnitude; thus we have Quantity of Movement in the form of number, dyad, TRIAD, decade, or in the form of extent apprehended in what we may call the amount of the Movement: but, the idea of Time we have not. That definite Quantity is merely something occurring within Time, for, otherwise Time is not everywhere but is something belonging to Movement which thus would be its substratum or basic-stuff: once more, then, we would be making Time identical with Movement; for the extent of Movement is not something outside it but is simply its continuousness, and we need not halt upon the difference between the momentary and the continuous, which is simply one of manner and degree. The extended movement and its extent are not Time; they are in Time. Those that explain Time as extent of Movement must mean not the extent of the movement itself but something which determines its extension, something with which the movement keeps pace in its course. But what this something is, we are not told; yet it is, clearly, Time, that in which all Movement proceeds. This is what our discussion has aimed at from the first: “What, essentially, is Time?” It comes to this: we ask “What is Time?” and we are answered, “Time is the extension of Movement in Time!” Ennead III,7,8
5. What then is the veritable nature of Number? Is it an accompaniment upon each substance, something seen in the things as in a man we see one man, in a being one being and in the total of presentations the total of number? But how explain the dyad and TRIAD? How comes the total to be unitary and any particular number to be brought under unity? The theory offers a multiplicity of units, and no number is reducible to unity but the simple “one.” It might be suggested that a dyad is that thing or rather what is observed upon that thing which has two powers combined, a compound thing related to a unity: or numbers might be what the Pythagoreans seem to hold them in their symbolic system in which Justice, for example, is a Tetrad: but this is rather to add the number, a number of manifold unity like the decad, to the multiplicity of the thing which yet is one thing. Now it is not so that we treat the ten things; we bring them together and apply the figure ten to the several items. Or rather in that case we say ten, but when the several items form a unity we say decad. This would apply in the Intellectual as in the sensible. Ennead VI,6,5
The single thing derives its unity by participation in Unity-Absolute; its being it derives from Being-Absolute, which holds its Being from itself alone; a unity is a unity in virtue of Being; the particular unity where the unity is a multiple unity is one thing only as the TRIAD is; the collective Being is a unity of this kind, the unity not of the monad but of the myriad or any such collective number. Ennead VI,6,10
In the Intellectuals, all, if the Absolute Living-Form, there is a multiple a TRIAD, let us say that TRIAD of the Living-Form is of the nature of essence: and the TRIAD prior to any living thing, TRIAD in the realm of Being, is a principle of essence. Ennead VI,6,16