Psychedelics are illegal not because a loving government is concerned that you may jump out of a third story window. Psychedelics are illegal because they dissolve opinion structures and culturally laid down models of behaviour and information processing. They open you up to the possibility that everything you know is wrong.
Terence McKennaAnd that we cannot go to space with our feet in the mud. Nor can we in fact turn ourselves into an eco-sensitive hallucinogenic-based culture on Earth unless we fuse these dichotomous opposites. It is only in a coincidencia oppositorum, a union of opposites, that does not strive for closure, that we are going to find cultural sanity. And this is the thing that the entheogens, the hallucinogens, deliver with such clarity and regularity. They raise paradox to a level of intensity that no one can evade.
Terence McKenna