|The Buddha smiling in stone (smiledesigners.co.in/osmanalar.girlshopes.com)|
|"Neurons to Nirvana"|
Nirvana is also very technically called "the unconditioned element," indicating its special standing among all the myriad of conditioned (composite) elements that form heaps. The Buddha was taking particular aim at the illusion of "self" or "ego" that arises from clinging to the Five Aggregates (explained by Bhikkhu Bodhi).
Further information is available in the book ZigZag Zen: Buddhism and Psychedelics, which provides a fuller discussion of the intersection of the two. The essay by Dokushô Villalba Sensei -- a Soto Zen master, the founder and spiritual director of the Spanish Soto Zen Buddhist Community and of the Luz Serena ("Serene Light") -- is particularly excellent.
[This book is] a treasure trove -- inspiring, frightening, powerful, funny, eye-opening, and a source of great wisdom on a subject that our society finds endlessly confusing. - Mark Epstein
"[It is] a must read for anyone who is concerned about the future of Buddhist practice." - Robert Thurman
"[It] touches all the high points... it is an important book." - Laura Huxley
"[It] challenges Western Buddhists to acknowledge their closeted psychedelic legacies, while confronting users with the troubling duality undermining any chemically dependent spiritual path." - Douglas Rushkoff