[The Teachings of Don Juan dealt with Castaneda's] own reaction to the experiences he submitted himself to, but it was also an attempt to see into a non-Western system of thought, to go further into the culture of the Yaqui Indians than anyone had penetrated before. The book has become something of a cult book in the United States where it is obviously grist to the mills of the expanding population of opters-out. For the first time, if I'm not mistaken, Castaneda's investigation of a Yaqui 'way of knowledge' has given some degree of cultural and historical authenticity to the use of what have become known as psychedelic drugs.

Whether in the spirit of true inquiry, or whether impelled by his bank manager …, Castaneda returned to Mexico in 1968 and took up the conversations with Don Juan that he had abandoned three years earlier.

A Separate Reality is an...