We want to acknowledge first the forebears of these books, the men and women who across many thousands of years have descended into dark caves, led community rituals, and explored consciousness-altering plants in order to encounter anew the world and their selves. We recognize our pioneers in Plato in the West, Pantanjali in the East, and other exemplars of first-rate intellects who laid the groundwork for integrating the insights of alterations of consciousness into our views of reality. Among the founders of modern psychology and anthropology there were notables such as William James and Andrew Lang who articulated and incorporated alterations of consciousness into their theories of human mind.
