Many Gnostics (especially the followers of Valentinius) taught that there was the One, the original, unknowable God (the Monad as it is called by Monoimus, or the first Aeon); and then from the One emanated other Aeons, pairs of lesser beings in sequence. (Valentinius listed 30 such pairs.) The Aeons together made up the Pleroma, or fulness, of God. The lowest of these pairs were Sophia and Christ.
Sophia's fears and anguish of losing her life, just as she lost the light of the One, caused confusion and longing to return to it. Because of these longings the matter (Greek: hyle) and the soul (Greek: psyke, ψυχή) accidentally came into existence through the four elements: fire, water, earth and air. The creation of the lion-faced Demiurge is also a mistake during this exile, according to some Gnostic sources as a result of Sophia trying to emanate on her own, without her male counterpart. The Demiurge proceeds to create the physical world in which we live, ignorant of Sophia, who nevertheless manage to infuse some spiritual spark into the creation of the Demiurge; that is the pneuma.
After this the savior (Christ) returns and lets her see the light again, bringing her knowledge of the spirit (Greek: pneumia, πνεῦμα). Christ was then sent to earth on the form of the man Jesus to give men the gnosis needed to rescue themselves from the physical world and return to spiritual world.
The three sensations experienced by Sophia creates three types of humans: hylics (bond to the matter, the principle of evil), psychics (bond to the soul and partly saved from evil) and the pneumatics that can return to the plemora if they achieve gnosis and can behold the world of light. The gnostics regarded themselves as members of this group.