The overriding problems are brought on by the existence of the ego, a maladaptive behavioral complex in the psyche that gets going like a tumor. If it's not treated - if there's not pharmacological intervention - it becomes the dominant constellation of the personality.
Terence McKennaThe psychedelic experience is simply a compressed instance of what we call understanding, so that living psychedelically is trying to live in an atmosphere of continuous unfolding of understanding, so that every day you know more and see into things with greater depth than you did before. This is a process of education.
Terence McKennaThe shaman is a very peculiar figure. He is critical to the functioning of the psychological and social life of his community, but in a way he is always peripheral to it. He lives at the edge of the village. He is only called upon in matters of great social crisis. He is feared and respected. And this might be a description of these hallucinogenic substances.
Terence McKenna