The Varieties of Psychedelic Epistemology

Is it possible to gain knowledge 1 by taking psychedelic 2 drugs?One influential answer is 'yes': according to this conception, by inducing mystical states of consciousness, psychedelics afford direct knowledge of supernatural, transcendent dimensions of reality.This is an entheogenic conception of the drugs as agents that "generate the divine within".A second influential answer is 'no': since materialism or physicalism 3 is true, there are no transcendent realities, and psychedelics just cause compelling hallucinations or delusions.This is a psychotomimetic or hallucinogenic conception of the drugs as psychosis-mimicking or hallucination-generating agents whose essential effects are antiepistemic 4; far from facilitating knowledge gain, psychedelics actively hinder it.A third, relatively unexplored view is that psychedelics can afford genuine epistemic benefits, even if materialism is true and there is no transcendent reality.From this perspective, the drugs' epistemic credentials do not depend on the existence of anything supernatural.Rather, psychedelics can afford genuine and sometimes transformative insights of a kind compatible with physicalism.Several authors have recently made proposals along these lines.Here I offer a 1 [This term is examined closely later in the chapter.Ed.] 2 My sole focus in this paper is 'classic', serotonin-2a agonist psychedelics such as LSD, psilocybin, mescaline, and DMT/ayahuasca; I reserve the term psychedelic for substances of this class. 3Despite philosophical complications, I will use the terms 'materialism', 'physicalism', and 'naturalism' interchangeably, to refer to views on which mind and consciousness always result from or depend on the complex activities of ultimately non-minded things (such as atoms): that is, views which hold that the mental is not fundamental to reality, but arises from or is constructed out of the non-mental.This excludes mind-body dualism, idealism and its variants (such as cosmopsychism), panpsychism and its variants (such as pan-experientialism and pan-protopsychism), and neutral monism (in Russellian and other versions.)It is also intended to exclude all metaphysically literal varieties of theism. 4'Epistemic' is a philosophical term meaning 'of or pertaining to knowledge'.