Well, firstly to touch on your rain man conversation, it seems to me that the average mind is well-rounded in its functioning; that is to say, it can do/process most things averagely: it can do math, it can think about poetry, it can help in socialization (the main goal of which is probably reproduction), it can allow you to partake in sports, but with its limited capacity, if it's to do all of these things with any sort of credibility, it needs to do them all with great limitation. When you have people who truly excel in something like idiot savants, their brain is focusing on one thing, and so the other areas truly suffer. So something you may wanna point out to your friend is that it is mainly autistic people and idiot savants who do the true suffering by average standards anyway. In terms of your friend not wanting to do shrooms, you may wanna suggest LSD, because whereas shrooms may bring up the question, and leave you in a condition unable to answer that question, I find that acid tends to leave you with the sort of clarity needed for tackling such situations. Anyway, that may or may not be a step in the wrong direction, but it's an option
"Science without religion is lame. Religion without science is blind" - Albert Einstein
"The Mighty One appears, the horizon shines. Atum appears on the smell of his censing, the Sunshine- god has risen in the sky, the Mansion of the pyramidion is in joy and all its inmates are assembled, a voice calls out within the shrine, shouting reverberates around the Netherworld." - Egyptian Book of the Dead
"Man fears time, but time fears the Pyramids" - 9th century Arab proverb