The first thing I brought back from a true drug voyage (a ++++ mushroom trip, my very first psychedelic experience) was a piece of note paper with the words 'people will do anything to be on television' scrawled on it.
As for the most profound, it's hard to put into words, though I identify with insights such as 'everything is consciousness' and 'everything is connected,' etc. One time on acid, I was having two simultaneous trains of thought, one about how people's individual interests seem random but in fact they are exactly what the world needs, in perfect proportions, and they are getting some kind of grand job done (sort of like 'everything happens for a reason,' but not quite); the other train of thought involved seeing a spatial representation of a logical argument in my head, how the pieces 'fit together' in this interlocking 3D structure. Then, both trains of thought sped up incredibly; I was flying through a tunnel; I saw an immense flash of white; and I felt I'd seen 'everything.' Everything there was to see. In a way I find the very idea foolish, but at the same time, the experience was so overwhelming that I have no choice but to believe in it.
Also, on MDMA, I realized that I could completely change my life, and I did. Perhaps that's more profound.
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mettray