Stating the obvious is sometimes useful. Assessing the significance and value of psychoactive substances in religion and contemplative practice is no easy matter. Psychedelics alter consciousness. Buddhist contemplative practices also alter consciousness. If ingesting a few psilocybin mushrooms did not lead to a significant and valued alteration of consciousness, it would not be appreciably different from eating a few baby portobellos. In both cases, eating the mushrooms would slightly dull any hunger one had been feeling, but the difference in the mushrooms eaten would not make any religious difference. Similarly for contemplative practices, if they did not alter consciousness in some notable and valued fashion, they would not differ in any religiously significant way from other practices—for example, playing a sport or musical instrument—that might be undertaken with comparable dedications of time and energy.

But what is consciousness, and what is entailed by its alteration? One possibility is that consciousness consists in “what it is like” to be experientially present. Given that, we might restate the obvious: the relative religious or spiritual value of psychedelic use and Buddhist practice does not depend on how each affects us physically, but rather on how they affect us phenomenally. Granted that, it would seem plausible to assess their relative religious or spiritual value by simply comparing the experiences derived from ingesting psychedelic compounds and those derived from traditional Buddhist practices. One could, for instance, use an instrument like the 30-item revised Mystical Experience Questionnaire (MEQ30) to establish the degree to which the experiences yielded by psychedelics and by Buddhist practice are phenomenologically equivalent.[1] Doing so, of course, would effectively discount the relevance of the different temporal scales at which psychedelics and Buddhist meditative practices yield phenomenal fruit, and the fact that Buddhist practices—and, indeed, much of what can be broadly classed as religious or spiritual practices—are not only embodied, but often ritually choreographed and collectively experienced. But if phenomenal content is what matters most, that is perhaps a justifiable discount.

Yet, even setting aside these concerns about embodiment, ritual, collective experience, and temporal scale, phenomenological content analysis only goes so far. Reasonably good evidence now exists that “mystical” experiences of oceanic boundlessness, ego-dissolution, and universal interconnectedness obtained through psychedelics can improve overall life quality and contribute therapeutically to symptom reduction in areas as wide ranging as cancer-related distress, substance abuse, and anxiety and depressive disorders.[2] But therapeutic efficacy is a much different kind of evaluative standard to meet than religious significance or spiritual value. Experiencing insight-delivering, mind-to-mind communication with a jaguar during an ayahuasca ceremony might result in improved life quality and readily qualify as mystical according to the MEQ30. That does not mean, however, that it would have any specifically religious significance or value in, for example, Christian, Muslim, or Buddhist contexts—an uncertainty greatly amplified by the theological and historical complexity of such so-called world religions. Assessing religious or spiritual value is highly context specific.

Matters become even more complicated if it happens that context-consonant and phenomenologically indistinguishable religious experiences can be obtained through both ingesting psychedelics and traditional contemplative practice. At one level, this could be seen as proof that psychedelics and traditional contemplative practices are just different means to “the same” religious end. Psychedelics simply offer a relatively effortless “shortcut.” Digging deeper, however, such phenomenal equivalence could be interpreted as proof that the experiences in question also have indistinguishable causal origins. Depending on how this is interpreted, psychedelically obtained insights undergo ontological inflation; they get to count as authentic or real. But it could also be interpreted such that traditionally obtained religious insights undergo ontological deflation; the fact that they can be generated by manipulating brain chemistry strongly suggests that they are not evidence of contact with or sublimation into a higher-order reality. When assessing the religious or spiritual significance and value of an experience, causal origins matter profoundly.

Recognizing this brings us up against a very hard—one might even say adamantine—problem: the causal origin of experience itself. This is not a problem that is unique to those seeking to clarify the spiritual significance of psychedelically induced experiences, although it is central, for example, to Chris Letheby’s “naturalistic spirituality” counter to the “comforting delusion objection” to psychedelic therapy.[3] In David Chalmers’s formulation,[4] the “hard problem” of consciousness is to explain the presence of experience reductively—that is, to explain how phenomenal events arise out of physical events. More provocatively stated, it is the problem of explaining how minds arise out of meat and motivations out of motion. Yet, as new materialists have pointed out, that problem goes all the way down the other way, too.[5] We now have very ample empirical evidence that the most basic subatomic constituents of the cosmos are neither particle-like nor wave-like until they are observed. Consciousness matters materially.

To return to the obvious one last time, both psychedelic use and meditative practices alter consciousness. But what does this mean, given that states of phenomenal awareness depend on or are significantly affected by neurochemical dynamics while those dynamics ultimately depend in turn on quantum-scale events that are significantly entangled with the dynamics of observational attention? Apparently, altering consciousness entails altering mind-brain-body-environment relations, and what we typically parse individually as subjective thoughts, brain activity, perception, and objective reality are related in a circular or network fashion rather than in a linearly reductive—either idealist or materialist—causal hierarchy. Any attempt to assess the relative values of psychedelic use and contemplative practice ultimately turns on what we mean by consciousness and exactly how it matters.

In what follows, I intend first to make a concise case for seeing that, if that causal circuit of mind-brain-body-environment relations is not to be a logically vicious circle, it must be given a nondualist twist, and that a contemporary, Buddhist theorizing of consciousness offers resources for doing so, with important implications for the relationship between psychedelics and religious and contemplative practice.[6] Following this, building on the nondualist theorizing of consciousness sketched in the first section, I will make a Buddhist case for seeing that, while the emphasis on the psychedelic experience might be consistent with a liberal individualist bias toward seeing personally attained insights as a benchmark of religious or spiritual advance, it is inconsistent with what I see as the core Mahayana Buddhist aim of realizing Buddha realms in which all things contribute to the elaboration of enlightening relational dynamics. Finally, I will draw on recent neuroscientific studies of psychedelics and meditation to rethink the dynamics of contemplative practice, the reality of interpersonal realization, the merits of group practice, and the inadequacy of techniques like mindfulness practice stripped of dharmic content and context. The religious or spiritual value of both contemplative practices and the use of psychedelics is not intrinsic to any experiences obtained through them; it is relational.

Here it is perhaps useful to stress that I will be offering a Buddhist perspective on the value of psychedelics, not the Buddhist perspective, and that I will be drawing freely from a wide range of Buddhist texts and traditions in much the same way that jazz musicians draw upon and improvise with the melodic, harmonic, and rhythmic elements of well-known “standards” to expand the horizons of musical anticipation. What follows is thus a first-person appropriation of and improvision on third-person Buddhist resources—most centrally, Chinese Chan, Yogacara, and Huayan—to reflect on the potential, relationality-transforming, therapeutic value of psychedelics.[7]

Theories of consciousness can generally be arrayed along three axes of conceptual tension: between materialist and idealist monisms; between dualisms in which consciousness is causally relevant with respect to matter and dualisms in which consciousness is causally irrelevant or epiphenomenal; and between representationalist (often computational) and enactivist (typically embodied and embedded) functionalisms. Today, as evidenced in Chalmers’s formulation of the “hard problem,” it is typically taken as axiomatic that what any viable theory of consciousness must explain is the presence of consciousness in an originally unconscious universe. Contemporary interest in panpsychism and neutral monism is rooted in recognition of the fact that—despite a great number of studies of the neural correlates of consciousness, some of which we will later have the occasion to consider—there continues to be no plausible account of how phenomenal experience is caused by or emerges out of physical entities and events. Either consciousness gets packed into the universe from the start as a basic constituent, or we risk sliding down the slippery slope to eliminativism, according to which the insolubility of the “hard problem” is a result of the fact that consciousness does not exist.[8]

Buddhist theorizing of consciousness is by no means monolithic. But a case can be made that experientially derived and therapeutically directed Buddhist conceptions of consciousness can be fitted into a theoretical basket that can be characterized as both nonreductionist and nondualist.[9] The apparent insolubility of the so-called hard problem is a function of presuming the ontological primacy of independently existing entities. The enlightening insight on which all Buddhist teachings pivot is that all things arise interdependently (see, e.g., Dīgha Nikāya 14.2.1ff.).[10] In later Mahayana traditions, this came to be referred to as the emptiness (śūnyatā) of all things—their lack of any abiding essence or fixed self-nature (sabhāva; svabhāva).[11]Most strongly stated, relationality is more basic than things related.[12]

Hence, although the earliest Buddhist texts gloss consciousness as that which emerges with the “contact” or interaction (phassa; sparśa) of sense organs and sense objects, the case can be made that interpreting this as a conjunction of preexisting elements can only be provisional—a mere convenience or convention. That, for example, is implied by the explicit claim that the phenomenal/physical system (nāmarūpa) both conditions and is conditioned by consciousness (Dīgha Nikāya 15.3). Consciousness, sense organs, and sensed environments are ultimately coeval.

Significantly, the Buddhist term for consciousness (viññāṇa; vijñāna) combines terms for differentiation and knowledge and might be somewhat literally rendered as “differential knowing” or “divisive knowing.” As I have argued elsewhere, for living beings like humans, consciousness matters foremostly in the differentiation of sensed and sensing presences, and consists more specifically in the elaboration of visual, auditory, gustatory, tactile, olfactory, and cognitive relations. Thus, visual consciousness consists in the elaboration of visual relations, and so on for the other four “materially” articulated sense consciousnesses. The sixth, mental sense consciousness (manoviññāṇa; manovijñāna) consists in the emergence and elaboration of intersensory relations—a collating of relational dynamics within and among the other five sensory realms as mental “objects” in relations with mind (citta) as an organ sensitive to them.[13]

This is not a value-free process. Prior to his enlightening insight into interdependence (see, e.g., Majjhima Nikāya 36),[14] the Buddha witnessed how the relational dynamics of countless past lives—his own and those of other sentient beings—had all been phenomenal/physical progeny of karma or the always revisable consonance obtaining among sustained patterns of values-intentions-actions and experienced relational outcomes and opportunities.[15] Mind-brain-body-environment relations are intention-conditioned. Thus, distinguishing between “this” and “that”—or between what something “is” and what it “is-not”—is not ultimately an act of discovery. It is an act of interest- and value-expressing disambiguation. This means, among other things, that the boundaries among things are perspectival “illusions,” like the horizon lines that we see when gazing out from a mountain peak. Rather than revealing absolute features of the world, the boundaries among things reveal features of our own difference-engendering presence. Matter is the definition of a point of view. What exists for us is what matters to us.[16] And the world that we experience is a record of how consciousness has been mattering.

To put this somewhat differently, the relationship between the phenomenal and the physical is one of nonreductive nonduality. As it came to be formulated in the Chinese Buddhist context, insight into nonduality does not entail seeing through or beyond phenomenal/physical differences to some underlying or overarching essential sameness. It consists in appreciating fully that each thing is both a cause of and caused by all other things. Our cosmos is one in which each thing is what it contributes functionally to the coherently patterned articulation (li, 理) of the totality of the cosmos.[17] In short, all things are “the same” insofar as they “exist” only in differing significantly from one another. Each thing ultimately is what it means to and for others.[18]

Consistently with this Chinese Buddhist view, I would suggest that the brain-body-environment system is best seen not as the cause of consciousness, but rather as its material infrastructure. Just as transportation infrastructures are the result of consistently sustained transportation practices, brain-body-environment systems are results of what consciousness has been doing: most rudimentarily, coherently differentiating matter and what matters. Brain-body-environment systems are creative products of consistently elaborated, values- and intention-manifesting sensory—that is, phenomenal/physical—relations.

To explain how karma operates, later Yogacara Buddhist theorists found it useful to posit two additional consciousnesses. For present purposes, these can be described as subjective or “afflicted mental” consciousness (kliṣṭamanovijñāna) and as a “storehouse” consciousness (ālayavijñāna) that mediates the differential ripening of the relational consequences of the other seven consciousnesses. Karma is generated and experienced as a function of differentiating among and either reinforcing or resisting the relational dynamics elaborated in/among the six sensory consciousnesses. The therapeutic import of this, as Chinese Chan Buddhists came to insist, is that unless one engages in sufficiently sustained meditative practices to open enactive possibilities for evaluating and intending otherwise, the dynamics of self-consciousness are typically shaped by bodily, conceptual, and linguistic habit formations (saṅkhāra; saṃskāra) in ways that are conducive to the phenomenal/physical ripening of karmic “seeds” or propensities for continued conflict, trouble, and suffering.[19]

I would argue for present purposes that this way of theorizing consciousness has four important implications. First, consciousness is relational and thus cannot be strictly located either spatially or temporally. Second, while consciousness entails agency, it does not necessarily entail an agential self or subjectivity. Third, consciousness is not unitary and is both functionally and qualitatively differentiated. And finally, while experiential freedom is by no means absolute, it is real. The phenomenal and the physical are perspectival artifacts of what consciousness does, and time matters continuously. The phenomenal/physical cosmos is not composed; it is improvised.

Differently stated, like the “two” sides of a Möbius strip—a topologically peculiar, three-dimensional construct that has only one side and one edge—the phenomenal “space of intentions” and the physical “space of causes” are globally continuous, but always and everywhere locally distinct. As the coherent differentiation of sensed and sensing presences, and more fundamentally of matter and what matters, consciousness and its material and immaterial infrastructures can alter intentionally in ways that are conducive to either continued conflict, trouble, and suffering or to realizing progressively liberating relational dynamics. Crucially for understanding the value of psychedelic use from a Buddhist perspective, this entails seeing that its value cannot be solely phenomenal. The value of consciousness-altering is not to be found primarily or exclusively in attaining certain kinds of subjective experience, but in altering the dynamics of physical/phenomenal differentiation and coevolution.

A crisp, but not yet cold fall afternoon. A century-old elm, its fissured bark vibrant along my spine. An exchange occurs, a merging of energy flows and memories, and then there is left nothing that is either other or self, only shared presence as human-elm-earth in pulsing coherence. It is suddenly, joyously obvious. Inside and outside, being and nonbeing, the finite and the infinite all appear locally distinct but are globally continuous, like the only apparently different sides or edges of a Möbius strip. Matter is the definition of a point of view. The myriad things are just one mind.

That afternoon in New Haven’s Grove Street Cemetery occurred almost 50 years ago to the day of writing the description above. It recalled an earlier, spiritually charged, childhood glimpse of nonduality and nonlocality. But unlike that earlier, seconds-long glimpse, this realization of “one mind” was sustained over the experiential peak of a “trip” induced by ingesting approximately 300 micrograms of LSD. It led to several years of experimentation using psychedelics to explore the frontiers of consciousness, a senior thesis on resolving the mind-body problem, and rekindled interests in meditation and Buddhism. It was not an uncommon story at the time.

In The Marriage of Heaven and Hell, William Blake opined that if only “the doors of perception were cleansed every thing would appear . . . as it is, Infinite.” When Aldous Huxley appropriated Blake’s metaphor of the “doors of perception” in his 1954 account of experimenting with mescaline (a derivative of the peyote cactus), he decisively hinged those “doors” with both science and religion.[20] Well-versed in Vedantic thought, Buddhism, and basic meditation practices, Huxley described the psychedelic experience as affording access to Mind at Large rather than the “measly trickle” that normally passes through what Henri Bergson had referred to as the “reducing valve” of the brain and nervous system—a way of going beyond the conceptual and perceptual walls imposed by languages and symbol-systems. His conviction was deep enough that, in an article published just a month before he requested a dose of LSD on his deathbed, he enjoined his readers to journey into “the nonverbal world of culturally uncontaminated consciousness,” learning to be mentally silent and practicing the art of pure receptivity.[21]

Huxley’s experiments with psychedelics and his convictions about their utility in opening doors to what he deemed to be experiences of universal and nonconceptual presence had powerful popular effects. Contemporary scientific and philosophical interests in altered states of consciousness (ASC) can be plausibly traced to William James and his early 20th-century observation that “normal waking consciousness, rational consciousness as we call it, is but one special type of consciousness, whilst all about it, parted from it by the filmiest of screens, there lie potential forms of consciousness entirely different.”[22] This plenitude of forms of consciousness ranges from mundane, involuntary states like drowsiness and daydreaming, to such dramatic and unwanted disruptions as those associated with schizophrenia or advanced dementia. But it also includes such voluntary and highly valued states of consciousness as those induced by meditative practices and—as Huxley and others began proclaiming in the early 1960s—the ingestion of psychedelic compounds.[23] After decades of scientific and philosophical indifference to consciousness and its multifarious forms, interest not only blossomed, as illustrated by Huxley’s final article being published in Playboy magazine in 1963, but also spread well beyond labs and conference rooms into the public.

Controversies were not long in following. Researchers in fields ranging from Psychology to Religious Studies attempted to determine whether psychedelic use could facilitate self-reported religious or spiritual insights, one of the earliest and most famous being the Good Friday Experiment conducted by Walter Pahnke as part of his doctoral dissertation research.[24] And a growing consensus prior to the US government’s criminalization of most psychedelics in 1966 was that their use, under the right circumstances, was conducive to experiences deemed religiously or spiritually significant.[25] The foundational question for many traditional religious specialists, however, was whether psychedelically induced reports of ego loss and cosmic unity were real and of equal value to those attained through mainstream contemplative practices, or if they were religiously insignificant and perhaps illusory (or even delusional) side effects of the “brain on acid.”

Within Buddhist communities, stances on the efficacy and importance of psychedelics varied and continue to vary considerably. Buddhist practice and psychedelics both enable perceiving the world and oneself otherwise. But it has been debated whether psychedelic experiences are comparable to tantric visions, to Zen kensho (seeing one’s true nature), or to the states of meditative absorption (jhāna) described in the Pāli Canon, or if they merely cloud the mind with content rising turbulently out of the storehouse consciousness. And it has been suggested by some that, used with an appropriate mindset and setting, psychedelics can reveal the conventional, conditioned, and constructed nature of what one had been taken to be “reality” or the “self,” and can accelerate and deepen Buddhist meditative practice.[26] But among practicing Buddhists who have had psychedelic experiences, the consensus seems to be that psychedelics can be useful “door openers,” but that they are not substitutes for—and may not even be proper supplements to—traditional Buddhist practice.[27]

Given the relational theorizing of consciousness offered above, the way that experience factors centrally into the variability of Buddhist views on psychedelics is instructive. There are both phenomenal and physical dimensions to altering consciousness, whether this is done meditatively or psychedelically. If consciousness is relational, altering it must have relational ramifications, and these ramifications cannot be restricted to those taking place “in the head.” An exclusive emphasis on phenomenal experience thus constitutes a bias—a narrowing of evaluative scope. If meditation and psychedelic use are undertaken for the purpose of attaining personal experiences of “ego loss” or “liberation from self,” for example, that bias is natural. I can lose my ego without you losing yours. Of the many people meditating in a Zen temple or monastery, perhaps only one or a small handful attain kensho, even after many years of effort, and their attainment cannot be claimed by or transferred to others.

Indeed, there is a tradition of idealizing solitary retreats and individual practice in Buddhism, most strikingly described in the Khaggavisāṇa-sutta as embarking on the Middle Way and wandering alone like a rhinoceros.[28] But there is an ambiguity in the text as to whether the encouragement to go alone on the path constitutes a personal ideal or if it is offered for purely pragmatic reasons. The early Buddhist tradition recognized the possibility of pratyekabuddhas or practitioners who attain enlightenment on their own and who afterward remain alone and eschew all teaching. The Buddha himself is said to have entertained doing so (see, e.g., Majjhima Nikāya 26.19). Instead, he embarked on a teaching career that led to a thriving voluntary community of practitioners, both ordained and lay. In fact, although he did practice alone and pass through various experientially extraordinary states (jhāna) on his way to enlightenment, what motivated the Buddha was not some extraordinary experiential attainment, but rather a method by means of which all sentient beings could be freed from compulsory forms and qualities of presence. Even if he undertook meditative practice by himself, he did not ultimately do so for himself.

The importance of that distinction is made apparent when the Buddha characterizes those who have embarked on and are traveling well along the path of Buddhist practice. He does not mention personal auras, or milestone experiences, or degrees of meditative absorption and mystical depth. Instead, he asserts that those who have come to be thus (tathāgata) and are fully enlightened will offer a set of teachings that is “lovely in its beginning, lovely in its middle, and lovely in its ending, in both spirit and the letter, and that displays the fully perfected and purified holy life.” Someone like this “dwells suffusing the whole world, upwards, downwards, across, everywhere with a heart filled with loving-kindness, abundant, unbounded” and then similarly suffuses the world with equanimity, compassion, and joy in the good fortune of others (Dīgha Nikāya 13.75ff.). Tellingly, this process of suffusing the environment is described as akin to a “mighty trumpeter making a proclamation to the four quarters”—something that is heard by one and all, no matter what they are doing or where they might be facing. Loving-kindness, equanimity, compassion, and sympathetic joy are not private feelings, in other words; they are powerfully propagating and environment-transforming relational qualities. Buddhist practice mediates personal transformations that ramify interpersonally.

In short, experiential attainments are not the point of Buddhist practice. Embodying wisdom and compassion are. Hence, in the Diamond Sutra (Vajracchedikā Prajñāpāramitā Sūtra), when the Buddha is asked by a close disciple what he attained upon realizing unsurpassed complete enlightenment (anuttarā samyak saṃbodhi), the Buddha’s disarming response was that “I did not attain a single thing” (chapter 22). This response can be variously interpreted. But I would argue that it is a deft way of making the epistemic point that the phrase “unsurpassed complete enlightenment” has no fixed and determinate reference, but also the soteriological point that practicing the Buddhist Middle Way is not a means of arriving at some predetermined or imagined goal.

If enlightenment is set up as a distant goal—something to attain—one will have to get halfway there first, but also previously halfway to that, and so on ad infinitum. The Middle Path will turn out to be interminable. One will have fallen into a spiritual version of Zeno’s paradox of motion, embarking on a recursively self-centered journey. Hence, Linji’s (d. 866) iconoclastic admonition that “if you see Buddha on the road, kill him,” and Huineng’s (638–713) declaration that “it is precisely a Buddha’s conduct that is Buddha” (Platform Sutra 42). To be a Buddha is to exemplify enlightening conduct, where the word translated here as “conduct” (xing, 行) originally referred to a crossroad and had the primary meanings of walking or traveling. “Enlightenment” does not designate a destination—somewhere you get to or something you get—but rather a direction. As Mazu (709–88) poetically describes it, the fruition of Buddhist practice is a fluid “harmony of body and mind that reaches out through all four limbs . . . benefiting what cannot be benefited and doing what can’t be done” (Xu zangjing, vol. 119, 408b).

The religious value of psychedelics, from this Buddhist perspective, is not determined by the experiences people have when their doors of perception and conception have been psychedelically cleansed or opened. It is determined by whether they step resolutely and effortfully through those doors, and by how they orient themselves thereafter.

The slip from ordinary to extraordinary reality occurred around the 14th hole, with the sky above the pine-framed fairway glowing that infinitely deep blue that is characteristic of a dry Florida winter night just before being pierced by first starlight. Grasses, trees, footsteps, a vital seamlessness. And then, at the edge of the fairway where one of the neighborhood’s brick-laid streets curved sharply to parallel the golf course, a dogwood twisted in embodied memory of violent collision when a drunk driver failed to negotiate the curve. A gut-punching dual lesson in attention lapse and organic resilience. And then an infinitely deep past plowed into a suddenly motionless present and it was suddenly clear: experience cannot be the answer. No experience—no matter how tragic or mystically wondrous—can ever fully confirm the ultimate reality of any other. All realities are affirmations of practice.

So began my commitment in late 1980 to stop hanging out in the “doorway” and to practice. Skeptical of organized religion and wary of the power of groupthink, I started out alone. This seemed consistent with what I had read about Buddhism. Although there are traditions of Buddhist practice (for example, Japanese Pure Land) that prioritize “other-power” or “outside help” (Japanese: tariki, 他力), “self-power” (Japanese: jiriki, 自力) or personal striving is generally stressed, and effort is prominently valorized by its inclusion both as the part of the Eightfold Path and as one of the six paramitas or modes of presence perfecting that are undertaken as part of the bodhisattva path.[29] Regardless of how one embarks on the Buddhist path, progressing on it requires effort.

Effort, however, can be misdirected, especially without an appropriate compass and/or a set of trustworthy fellow travelers—those referred to in the Khaggavisāṇa-sutta as “admirable friends” (kalyāṇa-mittatā; kalyāṇa-mitratā) with whom one does well to travel, friends whom the Buddha declares crucial to faring well, having embarked on the Eightfold Path (see, e.g., the Upaddha Sutta and Dighajanu Sutta). Although Buddhist traditions recognized the potential for solitary enlightenment as a pratyekabuddha, for most of those embarking on the Eightfold Path, guidance and companionship are necessary. Interestingly, contemporary neuroscientific studies of psychedelics and meditation can help us understand why that is so, but also why dis-embedding contemplative practices like mindfulness meditation from their original contexts can reinforce ego-centeredness and relational vulnerability rather than alleviating them.

Over the last decade, experimental approaches that blend third-person mappings of brain dynamics with first-person experiential reports have made it possible to “document” such dramatic alterations of consciousness as ego-dissolution under the influence of psilocybin—the transition from an ordinary and stably bounded sense of personal presence to presence freed from any clear self-other boundary.[30] It has been observed that such alterations of consciousness are correlated with significant increases in brain entropy—a marked reduction of the stability and integrity of well-established brain networks. Psychedelics “disorder” brain dynamics, disintegrating and desegregating ordinarily functioning brain networks, including the default mode network that is associated with the maintenance of self- or ego-defining narratives, thereby destabilizing neural constraints on emotion and perception and facilitating new neural connections.[31]

Moreover, these effects are not necessarily temporary. Altering consciousness psychedelically and meditatively has been shown capable of bringing about long-term and positive transformations in beliefs, outlook, and personality, including increased trait liberalism and decreased authoritarianism.[32] In Buddhist terms, psychedelically and meditatively altering consciousness—at least temporarily and perhaps lastingly—dissolves or dismantles the volitional compounds and enactive habits (saṃskāra) that ordinarily inhibit responsive readiness. That is, they work to alter the material/immaterial infrastructure of consciousness—making possible a reconfiguration of the interplay of especially the seventh and eighth consciousnesses.[33]

Consistent with this, it has been demonstrated that qualitatively altering consciousness correlates with changes in patterns of whole-brain dynamics,[34] that different types of meditation result in different patterns of brain oscillations, that these neural signatures of consciousness alteration vary along with differences in meditative skill,[35] and that these effects vary with expectations and context.[36] While novice meditators can consistently, but only temporarily, alter their brain dynamics, well-experienced meditators are able to realize stable reconfigurations of whole-brain dynamics. That is, they are able to consolidate patterns of neural readiness that offer support for consistently being conscious otherwise than “normal.”^[37]

Importantly, studies that blend first-person reporting with third-person neuroimaging have revealed, among other things, that the synchronizations of brain-wave oscillations that infrastructurally underwrite felt presence are not exclusively intracranial.[38] On the contrary, rather than reflecting only changes in an individual person’s interactions with their environment, continuous modifications of intra-brain oscillatory dynamics take place among experimental subjects. That is, studying the concurrent neural dynamics of people who are interacting socially reveals that neural rhythms are interpersonally conditioned. Brains are socially or relationally entangled.^[39]

With considerable implications for the efficacy of meditative community, it has been shown that functional interbrain entanglements are established during cooperation, and not during competition or merely simultaneous task performance. In an ingenious setup, experimental subjects were asked to complete a task with a distant partner who would be either another person or an AI program. Brain-wave synchronization among subjects occurred only when they believed they were working with another human, even though they were never paired with an AI program. That is, multiperson neural entanglement was affected by what the subjects thought or expected to be true.[40] Whether our brains become materially entangled is affected by the specifics of our thoughts and feelings—a finding that has important positive ramifications for the roles played by faith or confidence (saddhā; śraddhā) in Buddhist practice, but also for understanding the efficacy of both “old school” and digitally mediated indoctrination.

Taken together, these studies of the neural dynamics of multiple, socially engaged subjects make clear that consciousness is not essentially or “by nature” private and first-person singular, and that it is possible to actually—rather than just metaphorically—share experiences.[41] The neurally articulated infrastructure of consciousness extends beyond the cranium. Consistent with the nonreductive and nondualist theorizing of consciousness sketched earlier, we are confronting overwhelming empirical evidence of the need for a new “Copernican revolution”—a decentering of the brain and focusing on brain-body-environment systems as the basic relational units of sentient presence.[42] Moreover, as transcultural studies of consciousness are making evident, human mind-brain-body-environment systems are as culturally conditioned as are eating habits and family dynamics, and their dynamics are as much affected by efforts to achieve enhanced fit-within and fitness-in-response to sociocultural environments as they are in relation to bioecological environments. “In other words, our brains are biosocial,” concludes a 2013 article in Annual Review of Psychology. “The brain is . . . a relational organ that bridges the gap between the biological world of the organism and the social world of the environment and its culture.”[43]

Psychedelics and meditation practices are both capable of resulting in alterations of consciousness that can have potentially long-term and positive—including religiously or spiritually significant—effects. They can be relationally transformative. The empirical evidence just reviewed suggests that their efficacy is a function of their capacities for disrupting the infrastructure of consciousness in ways that are conducive to realizing—both materially and immaterially—otherwise inaccessible qualities of presence.

Returning to the analogy with transportation practices and infrastructures and pressing it a step further, I would say that both psychedelics and meditative training make it possible to go “off-road.” Like contemporary transportation infrastructures that support activities and experiences ranging from manufacturing and commerce to romantic encounters and artistic collaborations, but that also limit where it is possible to go and how, the neural/bodily/environmental and immaterial/conceptual/cultural infrastructures of human consciousness analogously support certain patterns of thought, feeling, and action, while also constraining the scopes and depths of our relationally dynamic interdependence. Going “off-road” opens possibilities for experiencing and relating otherwise.

Going “off-road” can be exciting. It can open sublime vistas and entirely new senses of time and space. It can also be dangerous in the absence of a reliable guide, compass, or map. Hence the centrality of teacher-student relations in Buddhist traditions and their recognition of potentials for “meditation sickness,” and the emphasis on appropriate set and setting in therapeutic uses of psychedelics as a hedge against unproductive and experientially traumatic “bad trips.”[44]

Given the apparent similarity of the effects of Buddhist meditation and psychedelic use on the neural infrastructure of human consciousness, the relative ease with which psychedelics enable going “off-road,” and historically reported evidence of the effectiveness of Buddhist meditation in generating and consolidating welcomed changes in outlook, it has been asked whether psychedelics and meditation might be combined to positive effect. In a study investigating the role of non-pharmacological factors in the psychedelic mediation of religiously significant experiences, for example, it was found that combining Buddhist mindfulness practice with the guided use of psilocybin significantly and positively impacted the meditative experience during a five-day retreat and amplified its desirable long-term ramifications when compared both with participants who engaged in the same five-day mindfulness retreat but who received a placebo and with participants who received the same dose of psilocybin but who engaged only in a simple neuropsychological task rather than Buddhist mindfulness.[45] Buddhist guidance is effective even for those chemically transported far “off-road.”

From a different angle, the Tibetan Buddhist contemplative framework of “view, meditation, action” (lta sgom spyod gsum) has been forwarded as a means of designing more effective protocols for psychedelic-assisted psychotherapy, including sessions where maladaptive conceptual narratives are worked through and beneficial ones introduced.[46] Here, an important consideration is the fact that in Tibetan Buddhism—and in Buddhist traditions more generally—moral clarity (śīla) is deemed foundational for ensuring that meditative concentration (samādhi) fosters wisdom (paññā; prajñā). Contemplative practice is generally preceded by months or years of moral cultivation. Hence, on the Eightfold Path, correct view, resolve, speech, livelihood, and conduct all “precede” correct effort, concentration, and wisdom.

The centrality of ethics and the concept of karma in traditional Buddhist contemplative frameworks might be dismissed or discounted as a relic of premodern cultural conservatism. That would seem to be the case for those who have divested mindfulness meditation of its explicit Buddhist trappings and presented it as a scientifically validated means to alleviating stress and leading happier and more productive lives, even if one happens to be a “wolf” of Wall Street or engaged in military special forces training. Techniques for maintaining calm focus, in and of themselves, do not necessarily entail calling into question the social injustices of market liberalism or the mass suffering caused by predatory geopolitics and militarism. Indeed, such “McMindfulness” techniques have been stridently critiqued as ironically enabling people to accept and adapt to socioeconomic or environmental conditions for which there could be no coherent Buddhist justification.[47]

Indeed, while both Buddhist meditative practices and psychedelics are apparently effective in disrupting the “default mode” operation of the neural infrastructure of consciousness, each affording access to potentially transformative and positive “off-road” experiences, it is a working familiarity with the Buddhist toolkit of concepts that makes it possible to critically assess the extracranial, material, and immaterial dimensions of the infrastructure of human consciousness, and to consider how best to rebuild or revise it. It is theoretically possible with sufficient mindfulness training or other comparable practices to live happily and without stress. Full stop. But if all things arise interdependently, if we are ultimately without-self and relationally constituted, and if wisdom and compassion are like the two wings of a bird, neither effective without the other, then there is no ultimate Buddhist warrant for any such individually achieved and sustained stop. Going “off-road”—even if it results in previously unimaginable experiences of peace and beauty—is not a Buddhist end in and of itself.

Here, it is useful to recall the Buddha’s declaration in the Diamond Sutra that, upon realizing unsurpassed complete enlightenment, he did not attain one single thing. Unsurpassed complete enlightenment does not designate a predetermined success condition—a destination at which one could arrive. The aim of Buddhist practice as exemplified by the bodhisattva ideal is not attainment, but continual improvement: realizing hitherto unobvious ways of virtuosically embodying wisdom and compassion. As in musical virtuosity, this means exceeding current standards of excellence in ways that set new standards of effort and that surprisingly and gratifyingly extend horizons of both anticipation and appreciation. The description of the bodhisattva path as endless is not mere hyperbole. The potential for an increasingly valued presence is without limit.

That potential is relational. Evidence of the interpersonal conditioning of the neural rhythms of those who are interacting socially, especially improvisationally, suggests that narrative celebrations of spontaneous mind-to-mind transmissions in Chan/Zen/Soen Buddhism may be much more than mere rhetoric—nothing more than instrumental means for securing lineage legitimacy. Indeed, this scientific evidence surprisingly invites deeper appreciation of the religious and spiritual—not just institutional—potency of monastic retreats and practice communities. There is work that must be done on one’s own. But there is also work that is best carried out shoulder to shoulder—most crucially and fundamentally the hard labor of breaking down infrastructural blocks to relating ever more freely.

Questions about the Buddhist value of psychedelic experiences may finally be unanswerable. That is partly because psychedelic experiences, like all things and events, have no abiding or essential nature. They are empty. Emptiness, however, is not vacuous absence. It is ontological openness. Although we customarily refer to ourselves and other life-forms as sentient beings, all are in fact sentient becomings. At the very least, psychedelics can help make clear that there are possibilities for becoming otherwise. Whether those possibilities are enacted in ways that are consonant with realizing ever more liberating relational dynamics is not intrinsic to psychedelic experiences as such. Yet, as the Buddha’s six years of ascetic training made evident, that is also true of contemplative practices. Meditation and other contemplative practices are also not intrinsically liberating.

Assessing the Buddhist significance and value of altering consciousness does not depend ultimately on the method of alteration used, but on the quality of motivations involved. It is the depth and consistency of becoming more appreciatively and compassionately intent on enlightenment (bodhicitta) that matters most.

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