You are in possession of an exquisite machine motionlessly buoyant in the softly circulating fluids of your skull. A world-building machine. And psychedelic molecules are the tools for tuning and operating this machine... From LSD to magic mushrooms to DMT to Salvia divinorum, psychedelics are used across the globe to stimulate the brain and change the nature of the subjective world. In sufficient doses, these molecules have the potential, not only to alter the structure of the normal waking world, but to replace it entirely - to hurl the tripper into fantastical realms of immense complexity and strangeness, bursting with extraordinary ecologies of apparently intelligent and communicative beings. Whilst these effects seem almost impossible to comprehend, let alone explain, as our understanding the brain's ability to construct our model of reality in normal waking life deepens, the mechanism by which psychedelic molecules perturb its world-building machinery such that entirely novel and unimaginably bizarre worlds emerge begins to reveal itself. Chemical pharmacologist and neurobiologist Dr. Andrew R. Gallimore (author of Alien Information Theory: Psychedelic Drug Technologies and the Cosmic Game) explains in unprecedented depth and detail how psychedelic drugs interface with the human brain, alter the structure and dynamics of the experienced world, and rapidly and efficiently switch the brain's reality channel, opening up a vast number of alternate worlds for discovery and exploration. Ultimately, using both molecular and post-molecular technologies, humans will be able to enter countless different worlds at will, to establish communication with the beings resident therein, and to engineer reality itself.