Are humans unwitting partners in evolution with psychedelic plants? Darwin's Pharmacy shows they are by weaving the evolutionary theory of sexual selection and the study of rhetoric together with the science and literature of psychedelic drugs. Long suppressed as components of the human tool kit, psychedelic plants can be usefully modeled as "eloquence adjuncts" that intensify a crucial component of sexual selection in humans: discourse.

Psychedelic plants seduce us to interact with them, building an ongoing interdependence: rhetoric as evolutionary mechanism. In doing so, they...