The later Neoplatonists began discussing time in a fairly unique and important way. In his commentary on Plato's Timaeus, Iamblichus connects the intellectual triad of Being, Life, and Mind with three "moments" connected to Aion, Eternity, the pre-essential Demiurgos. These moments have nothing to do with temporal time as Aristotle understands it in the Physics, i.e. "movement in respect of the before and after: (Physics, IV.11s), or movement in time. While this may hold true for the realm of generation, neither the noetic/noeric (intelligible/intellective) nor psychic (soul) levels of reality function this way. Common time, which relies on both physical space and movement, is not at all present above the physical realm.
The three moments of the noetic realm deals not with chronological order, but ontological order. For example, the noetic realm, or a being of the noetic realm, such as one of the gods, exists in and of itself. This is the entity's "unparticipated" aspect. The second moment is the "participated" aspect, or how an entity is engaged in by an ontologically posterior entity. In other words, how we might encounter and interact with a god or archangel. Finally, there is the aspect that is "in participation." This is how a ontologically prior reality or entity is manifested in or through an ontologically inferior entity. That is to say, this is a god, angel, daimon, etc. as we participate in it and bring it through into the world. Importantly, it appears that these three moments can be extended, after a fashion, to the realm of the One or God and to the psychic realm.
The idea of participation is very important. Either an entity, such as a human soul, has some quality in full or it lacks it. A quality in full is completely known and understood. One does not have to think about this quality or element of knowledge, it is simply there. To the degree that a quality is lacking, an entity must participate in a superior being that embodies that quality. For instance, according to the later Neoplatonists, the human soul comes, ultimately, from the Whole Soul, which is below the level of the Divine Mind. This means human souls do not have the divine mind in full and must instead participate in it.
So, what does this have to do with psychology? You may recall the famous inscription over the entrance to the Oracle at Delphi: Know Thyself. The seemingly simple command is deceptive in its simplicity. For a god or angel this is a simple matter, for the essence of a god or angle is single. However, according to the later Neoplatonists, this is not true of humanity for we alone of all the entities in the great Chain of Being, have a dual essence: one inclining towards our divine nature, one inclining towards generation. This division, which leads us to incarnation over and over again, makes knowing ourselves extraordinarily difficult.
In part II, we will look at how the three moments of Aion are related to this divine command.