Nous was an essentially important part of Neoplatonic, Christian Gnostic and Hermetic understanding of the Universe.
Let’s go slowly, first with the Neoplatonists, then with Christian Gnostics, and finally with Hermetists.
The Neoplatonist Plotinus (d. 270) speculated that through emanation the One gave rise to Divine Mind (“Nous”) believed to contain all the forms and thoughts of a universal intellect. Nous is a realm of Platonic Ideas. It is also a plane of perfect knowledge. From Nous emanates the World Soul linking the intellectual and material worlds. For Plotinus at the top is the One and at the bottom is the physical universe of space and time perceptible to the senses. Humans have a leg in two realms: one in the realm of the physical world and the other in the Divine Mind. Plotinus metaphorically identified the Nous as Zeus.
The Neoplatonist Porphyry (d. 305 CE) believed that philosophy could connect the intellect to the intelligible realm or Divine Mind.
The Neoplatonist Iamblichus (d. 325) divided Nous to an Intelligible Nous and Intellectual Nous, each of which he subdivided to the triad of Limit, Unlimited and the One Being, which are super-terrestrial gods. Below them there are 360 celestial beings, 22 orders of sub-celestial gods and 42 orders of natural gods. Inferior to them are angels, demons and heroes.
For the Neoplatonist Proclus (410-85) from the The One comes by the first emanation, Henads. Proclus replaced the Nous with a triad Being-Life-Nous, and between Being and the One inserted a further series of principles, the Henads who mediate between the One and lower realities.
Theios Nous, in Neoplatonism, this is the Divine Name of the Sun. It signifies Divine Intelligence. It looks like that in Neoplatonist thought each planet has its own logos too.
The Christian Gnostics borrowed much of their thoughts from the Neoplatonists. For example, the author of the appendix to Tertullian De Praescr tells that Abraxas gave birth to Mind (Nous) and the 365 heavens, and finally that Christ was not sent by the Maker of the world but by Abraxas. Upright Nous is also mentioned as the God’s name in the Gnostic scripture The Thought of Norea. According to the Gnostic Valentinians in the first generation of Eons consist of Bythos (Βύθος – The One) and Sige (Σιγή – Silence), while the second is Nous (Νοΰς, Mind) and Aletheia (Άλήθεια – Veritas, Truth).
In Hermeticism, Ogdoad represents the sphere in which the word of God, the Logos comes from Nous. That is why it is said that the Logos is the son of Nous, or in other words, that the Word is the son of the Mind. Poemanders is personification of the Mind of God. Poemanders was revealed to Hermes Trismegistus and containing visions of the creation of the world, nature and destiny of mankind, which are partly in accordance and partly in contradiction with the book of Genesis of the Old Testament. The fall is described as the descent of primordial man through the sphere of the planets into the world of nature, which was not a consequence of disobedience, but an act of love accompanied by God’s blessing. Man passed through the celestial sphere of stars and planets, until he reached the Moon, the lowest planet. When he looked into the water from there, he saw his own shadow, fell in love with it, so he was attracted to the irrational sphere of matter and became a deity with one half and an animal with the other. They represent the power of harmony, but also the source of tendencies that lead people to evil. People who know that the body is transient, after death can rise above the seven spheres and enter the eighth sphere where they will hear the hymn of the Father and become part of the power of his Mind (Nous).