Mind Hallucinogens and the I Ching, New York: HarperCollins, 1993.
The Invisible Landscape is the most esoteric of the three Terence McKenna books reviewed here. Many of the topics he treats in his other books, he treats here as well, but he presents them under a slightly different light, or in more subtle language.
His standard theme psychedelics, for example, assumes a new dimension, together with his regard upon science:
Psychedelic drugs have always been and remain the most useful molecular probes available to science for exploring the relationship between the subjective experience of mind and neurobiological processes. /Preface XIX
Despite its pretensions to objectivity, science, like any other human institution, places a certain vested interest in its own self-preservation; thus it is likely to be less than enthusiastic, if not openly hostile, toward any investigative strategy that could potentially call its most basic assumptions in question. /Id.