But there was a door blocking their way from learning the secrets within the mind. It would not be until the summer of 1960 that Leary and his colleagues would find the key to unlock this door.
That summer Leary and a 5 of his friends (other Harvard Psych professors) decided to go to Mexico for a trip. There they met Gerhart Braun an anthropologist-historian of the University of Mexico. After a dinner and discussion of philosophy, Braun told them that within the hot, tropical jungles of Mexico grows a power hallucinogen known to the Ancient Aztecs as Teonanacatl, or "flesh of the gods." These magic mushrooms of Mexico had a long history surrounded by religious and ceremonial use. The Catholic Church feared this drug would encourage devilish worship in turn would tarnish the Catholic belief, and banned these "devil" drugs, so effectively that botanists denied of there very existence until they were re-discovered in the 50's. It turned out that Braun had collected of some these mushrooms earlier that day and offered to try them with the Harvard faculty. So Leary decided to try the so-called hallucinogen. Two out the five abstained and would record the others experience on paper. .
Leary wrote of what would be come his spiritual experience with psilocybin: "I began to feel strange. Like going under dental gas. Mildy nauseous. Detached. Moving away, away from the group on a terrace under the bright Mexican sky. Everything was quivering with life, even inanimate objects. I gave way to the delight, as mystics have for centuries when they peeked through the curtains and discovered that this world -- so manifestly real -- was actually a tiny stage set constructed by the mind. There was a sea of possibilities out there (in there?), other realties, an infinite array of programs for other futures.".
After the 4-hour trip ended Leary and his fellow colleagues came back changed. They came back realizing about higher levels of perception where one sees realities a hundred times more beautiful and meaningful than the reassuring familiar scripts of normal life.