Earlier quoted context omitted.
"Shaman/Medicine men have been having visions for years and using substances to get closer to nature since humankind started - agree with your point about "rediscovery"." So have completely insane people. If only we had some way to tell when people were full of shit...oh wait, thanks science!
In the case of most pharmaceuticals, the best science can tell us is that this chemical correlates with that effect. We still don't know how aspirin does what it does for chrissake -- just that it does it. The only difference between that and a shaman is clinical trials. (Except, of course, that the shaman actually has an explanation for how his medicine works, however anathema it may be to the traditional Western mi…
http://en.wikipedia.org/wiki/Mechanism_of_action_of_aspirin
> The only difference between that and a shaman is clinical trials.
Yeah, man, totally. Well, that and safe dosage, drug interactions, toxicity profile, half-life, chemical formula, side-effects...
> Except, of course, that the shaman actually has an explanation for how his medicine works
This merely proves that anyone anywhere can invent a just-so story.