PrimalSoup said:

SFAIK the Catholic doctrine of transubstantiation holds that the bread and wine become literally the actual body and blood of Christ in the sacrament of the Eucharist, not merely symbolically.  What would be the point otherwise?  It's supposed to be miraculous...

What I can say from experience is that the mushrooms connect me WITH some sort of source of being.  They are not themselves the source of this source, or some sort of deity.  They are conduits, IME, to the hyperdimensional reality that underpins our own.  They invoke the holy and thus render it accessible and attainable - but only with the synergistic relationship that occurs between the human and the mushroom when one consumes the other.  In this sense we sacrifice their body to our purposes.  It's not a far stretch - and never has been if history is any guide - to extend the "sacrifice" to other forms, particularly when the preferred sacrament isn't available. 

However, this source of being that one connects with is generally incapable of being reliably interpreted back here in our ordinary reality.  Hence people get all sorts of different "revelations" and "truths" from it, all stamped with an incontrovertible evidentiary quality (aka qualia) of immense relevance and accuracy - an emotional trap if you don't recognize the basic inapplicability of the one realm to the other.  Those woods are thick.

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