The Stoic and Gnostic movements, with their striving for apathy or a speedy escape to the world above, are representative of the former, and the Platonic and mystical traditions, with their inclination to kill off the flesh or pass over embodied existence, of the latter. That these attractive errors did not become the mainstream is due to the resistance of the pragmatic ethical systems,
I emphasize the twisting immanence of the weird here because, though we will be meeting some wild visions ahead, including gnostic downloads and alien beings, I want to understand these extraordinary experiences not as signs of a “separate reality” but as manifestations or mutations of this one.
I confess to a rather shallow understanding of this heretical branch of Christianity, or whatever mode of thought the word refers to. They had the idea that the world we perceive is the work not of God but of an evil false god, the demiurge. That's pretty metal. They also have a reputation as hippies who thought early on that Christianity meant a sort of personal divinity and liberation.
There seems to be a kind of dualistic polarity between the world (gross, evil, painful. demonic) and the spirit, which is repressed, trapped in a body, oppressed by the world, in need of liberation.
This spirit seems to manifest in the WS sphere as a hatred, not of the world per se, but of materialism in its various forms. They see the face of their enemy there.
PKD version (a lot of what I know about gnosticism comes filtered through Dick's work)