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The Ayahuasca Experience



from the Introduction: Amazonian Vine of Visions
by Ralph Metzner, Ph.D.

Ayahuasca is an hallucinogenic Amazonian plant concoction, that has been used by native Indian and mestizo shamans in Peru, Colombia and Ecuador for healing and divination for hundreds, perhaps thousands of years. It is known by various names in the different tribes, including caapi, natema, mihi and yajé. The name ayahuasca is from the Quechua language: huasca means "vine" or "liana" and aya means "souls" or "dead people" or "spirits". Thus "vine of the dead", "vine of the souls" or "vine of the spirits" would all be appropriate English translations. It is however slightly misleading as a name, since the vine Banisteriopsis caapi is only one of two essential ingredients in the hallucinogenic brew, the other one being the leafy plant Psychotria viridis, which contain the powerful psychoactive dimethyltryptamine (DMT). It is the DMT, derivatives of which are also present in various other natural hallucinogens, including the magic mushroom of Mexico, that provides visionary experiences and thus access to the realm of spirits and the souls of deceased ancestors. But DMT is not orally active, being metabolized by the stomach enzyme monoamine oxidase (MAO). Certain chemicals in the vine inhibit the action of MAO and are therefore referred to as MAO-inhibitors: -- their presence in the brew makes the psychoactive principle available and allows it to circulate through the bloodstream into the brain, where it  triggers the visionary access to otherworldly realms and beings. The details of this remarkably sophisticated indigenous psychoactive drug-delivery system, and the history of its discovery by science, will be described and explored in this volume.

As a plant-drug or medicine, ayahuasca and its molecular essences is one of a group of similar substances that defy classification: they include psilocybin derived from the Aztec sacred mushroom teonanácatl, mescaline derived from the Mexican and North American cactus peyote, DMT and various chemical relatives derived from South American snuff powders known as epena or cohoba, the infamous LSD derived from the ergot fungus that grows on grains, ibogaine derived from the root of the African Tabernanthe iboga tree... and many others. As plant extracts or synthesized drugs, these substances have been the subject of a large variety of scientific research approaches over the past fifty years, particularly as to their potential applications in psychotherapy and in the expansion of consciousness for the enhancement of creativity and as amplifiers of spiritual exploration. They have been called psychotomimetic ("madness mimicking"), psycholytic ("psyche loosening"), psychedelic ("mind manifesting"), hallucinogenic ("vision inducing") and entheogenic ("connecting to the sacred within"). The different terms reflect the widely differing attitudes and intentions, the varying set and setting with which these substances have been approached. We will be describing the Western scientific psychological and psychiatric approaches to ayahuasca in this book also.

The concepts of shaman and shamanism are not native to South America; they are derived from Siberian cultures. In recent years they have come to be used for any practice of healing and divination that involves the purposive induction of an altered state of consciousness, called the "shamanic journey", in which the shaman enters into "non-ordinary reality" and seeks knowledge and healing power from spirit beings in those worlds. The two most widespread shamanic techniques for entering into this altered state are rhythmic drumming, practiced more in the Northern Hemisphere (Asia, America and Europe) and hallucinogenic plants or fungi, practiced more in the tropics and particularly in Central and South America. Ayahuasca is widely recognized by anthropologists as being probably the most powerful and most widespread shamanic hallucinogen. In the tribal societies where these plants and plant preparations are used, they are regarded as embodiments of conscious intelligent beings that only become visible in special states of consciousness, and that can functions as spiritual teachers and sources of healing power and knowledge. The plants are referred to as "medicines", a term that means more than a drug: something like a healing power or energy that can be associated with a plant, a person, an animal, even a place. They are also referred to as "plant teachers" and there are still extant traditions of many-years long initiations and trainings in the use of these medicines. The use of ayahuasca in the context of Amazonian shamanism is another topic of this book.

Many Western trained physicians and psychologists have acknowledged that these substances can afford access to spiritual or transpersonal dimensions of consciousness, even mystical experiences indistiguishable from classic religious mysticism, whether Eastern or Western. The new term "entheogen" attempts to recognize this element of access to sacred dimensions and states. In the North American peyote church, the African Bwiti cult using iboga, and in several Brazilian churches using ayahuasca, we have seen the development of authentic folk religious movements that incorporate these entheogenic or hallucinogenic plant extracts as sacraments -- developing both syncretic and highly original forms of religious ceremony. The Brazilian ayahuasca-using churches by now have thousands of followers, both in South America and in North America and Europe, and they are growing in numbers and influence. So here we have a substance that has profoundly affected the transformation of individuals, now beginning to bring about something like a cultural transformation movement. These facets of the ayahuasca story will also be explored in this book.

As hundreds, perhaps thousands, of Westerners and Northerners have participated in shamanic practices involving ayahuasca (as well as other medicines and non-drug practices) and joined the ceremonies of the various ayahuasca churches, it has become clear that there is a profound discontinuity in fundamental worldview and values between the Western industrialized world and the beliefs and values of traditional shamanistic societies and practicioners. A powerful resurgence of respectful and reverential attitudes toward the living Earth and all its creatures seems to be a natural consequence of explorations with visionary plant teachers. As such, this revival of entheogenic shamanism can be seen as part of a world-wide response to the degradation of ecosystems and the biosphere -- a response that includes such movements as deep ecology, ecofeminism, bioregionalism, ecopsychology, herbal and natural medicine, organic farming and others. In each of these movements there is a new awareness, or rather a revival of ancient awareness of the organic and spiritual interconnectedness of all life on this planet.

As a psychologist, I have been involved in the field of consciousness studies, including altered states induced by drugs, plants and other means, for over 35 years. In the 1960's I worked at Harvard University with Timothy Leary and Richard Alpert, doing research on the possible therapeutic applications of psychedelic drugs, such as LSD and psilocybin. During the 1970's the focus of my work shifted to the exploration of non-drug methods for the transformation of consciousness, such as are found in Eastern and Western traditions of yoga, meditation and alchemy and new psychotherapeutic methods using deep altered states. During the 1980's I came into contact with the work of Michael Harner and others, who have studied shamanic teachings and practices around the globe, involving non-ordinary states of consciousness induced by drumming, hallucinogenic plants, fasting, wilderness vision questing, sweat-lodge and others. Realizing that there were traditions reaching into pre-historic times of the respectful use of hallucinogens for shamanic purposes, I became much more interested in plants and mushrooms that have a history of such use, rather than the newly discovered powerful drugs, the use of which often involves unknown risks. I have come to see the revival of interest in shamanism and sacred plants as part of the world-wide seeking for a renewal of the spiritual relationship with the natural world.

Over the past two millenia Western civilization has increasingly developed patterns of domination based on the assumption of human superiority. The dominator pattern has involved the gradual desacralization, objectification and exploitation of all non-human nature. Alternative patterns of culture survived however among indigenous peoples, who preserved animistic belief systems and shamanic practices from the most ancient times. The current intense revival of interest in shamanism, including the intentional use of entheogenic plant sacraments, is among the hopeful signs that the split between the sacred and the natural can be healed again.

A recognition of the spiritual essences inherent in nature is basic to the worldview of indigenous peoples, as it was for our own ancestors in pre-industrial societies. In shamanistic societies, people have always devoted considerable attention to cultivating a direct perceptual and spiritual relationship with animals, plants and the Earth itself with all its magnificent diversity of life. Our modern materialist worldview, obsessively focussed on technological progress and on the control and exploitation of what are arrogantly called "natural resources", has become more or less completely dissociated from such a spiritual awareness of nature. This split between human spirituality and nature has some roots in the ancient past of Western culture, but a major source of it was the rise of mechanistic paradigms in science in the 16th and 17th century.

As a result of the conflict between the Christian church and the new experimental science of Newton, Galileo, Descartes and others, a dualistic worldview was created. On the one hand was science, which confined itself to material objects and measurable forces. Anything having to do with purpose, value, morality, subjectivity, psyche or spirit, was the domain of religion, and science stayed out of it. Inner experiences, subtle perceptions and spiritual values were not considered amenable to scientific study, and came therefore to be regarded as inferior forms of reality, -- "merely subjective" as we say. This encouraged a purely mechanistic and myopically detached attitude towards the natural world. Perception of and communication with the spiritual essences and intelligences inherent in nature have regularly been regarded with suspicion, or ridiculed as misguided "enthusiasm" or "mysticism".

This strange coure of events has resulted in a tremendously distorted situation in the modern world, since our own experience, as well as common sense, tells us that the subjective realm of spirit and value is equally as important as the realm of material objects. The revival of animistic, neo-pagan and shamanic beliefs and practices, including the sacramental use of hallucinogenic or entheogenic plants, represent a re-unification of science and spirituality, which have been divorced since the rise of mechanistic science in the 17th century. I believe spiritual values can again become the primary motivation for scientists. It should be obvious that this direction for science would be a lot healthier for all of us and for the planet, than science directed, as it is now primarily, towards generating weaponry or profit.

In this book, we will provide a look at the phenomenon of ayahuasca both from the perspectives of objective natural and social science (botany, chemistry, pharmaology, medicine, anthropology and psychology) and from the point of view of subjective experience -- a realm usually considered not amenable to scientific investigation. To do so requires a new look at the epistemology of consciousness.

Science and Experience -
Toward an epistemology for the study of consciousness
Western science in general and psychology in particular has never been comfortable with the study of the subjective side of life, with qualities of experience, purposes, intuitions, altered states or spiritual aspirations. Under the sway of the Newtonian-Cartesian mind-matter dichotomy, consciousness and experience were seen as belonging to the realm of religion, and science agreed to stay out of it. Later, as the ideological hold of the Church diminished and the materialist paradigm became paramount, consciousness and all subjective experience became even more firmly banished from scientific discourse.

In the 19th century, the German social philosopher Wilhelm Dilthey attempted to establish the "mental sciences" (Geisteswissenschaften), on an equivalent footing to the "natural sciences" (Naturwissenschaften). This idea never really took hold in the English-speaking world. Instead, the social sciences (psychology, sociology, anthropology, political science) adopted and imitated the empirical observational and quantitative analytical methods of the natural sciences. In psychology, the only observations that qualified as "scientific" were observations of behavior -- to the extreme of B.F. Skinner's behaviorism, in which mental states were said to be in an unknowable "black box". Although the influence of strict behaviorism in psychology has waned in the latter half of the 20th century, the ideological commitment to a materialist worldview has not. In the leading paradigms of cognitive psychology or cognitive science (which includes brain sciences, computer modeling, information systems and the like) consciousenss is still treated as something to be explained (i.e. explained away) in the supposesdly more "real" terms of "neural nets", "brain circuits" and the like.

In the latter half of the 19th century a European philosophical movement took a completely different and new approach to the study of consciousness. The German mathematician/philosopher Edmund Husserl (1859 - 1938) originally conceived of his phenomenology as an attempt to rescue philosophy and the quest for absolute knowledge from the "naturalism" and relativism of the newly arising experimental psychology. He criticized the psychophysical method of Wilhelm Wundt and G.T. Fechner as providing only correlations between subjective events and physical events, and ignoring the possibilities of "pre-understanding" of what consciousness was essentially. For Husserl, the abstract truths of mathematics are essences that are grasped by the mind directly, without relative or empirical observation. He proposed phenomenology as the method for directly arriving at essential and universal knowledge about the nature of consciousness and meaning, in part by clarifying the implicit pre-understandings that underlie other psychological approaches.

A core concept of Husserl's phenomenology of consciousness is intentionality : consciousness is always intentional, always "of" or "about" something, always directed, like an arrow or a mathematical vector, toward some object of meaning. The objects that consciousness intends can be external, or they can be internal aspects of our own experience. Because intentional consciousness is always "constituting" the essential features of the various domains of existence, both external and internal, consciousness has a fundamental "ontological priority" -- it is the "supporting ground of reality". The focus on intention as the fundamental constituting attribute of consciousness is congruent with the emphasis on "set (and setting)" as the prime determinants of altered states. The ontological primacy of consciousness in Husserl's phenomenology is consistent with the worldview of the mystics in Eastern and Western traditions as well as the insights coming from profound altered states.

A further innovative contribution to the phenomenology of consciousness was made by the French philosopher Maurice Merleau-Ponty (1908 - 1961). In his work, the focus of interest shifts from the subjective mind to the subjective body, or bodily experience (le corps propre). For Merleau-Ponty, perception is an inherently creative, participatory activity between the living body and its world. All subjectivity or consciousness presupposes our inherence in a corporeal world, a world that we perceive as having depth, intimacy and horizon. The ecophilosopher David Abram (1996) has shown how in many ways Merleau-Ponty's later thought, in his work The Visible and the Invisible, anticipates the deep ecologists and others who are looking to develop a new conscious awareness of our embeddedness in the world of Nature.

The American philosopher William James (1842 - 1910) approached the psychology of consciousness in his characteristic multifarious manner. He may have been the first person to use the concept of "field" in talking about consciousness: human beings have "fields of consciousness", which are always complex, -- containing body sensations, sense impressions, memories, thoughts, feelings, desires and "determinations of the will", in fact "a teeming multiplicity of objects and relations". He made it clear that his famous "stream of thought" image actually meant not just thoughts, but images, sensations, feelings, etc. He wrote that the mind "seems to embrace a confederation of psychic entities," -- a statement that contemporary explorers of states of consciousness would readily relate to. In addition to multiplicity, James was greatly impressed by the selectivity of consciousness. In his Principles of Psychology he wrote, "The mind is at every stage a theatre of simultaneous possibilities. Consciousness consists in the comparison of these with each other, the selection of some and the suppression of the rest by the reinforcing and inhibiting agency of attention." (James, 1890/1952, p. 187). The self was the unifying principle in the multiple fields of consciousness, and the active, selective agency that expressed itself through its interests and the directing of attention.

While drawing attention to the multiplicity and selectivity of ordinary consciousness and attention, James also explored the paranormal and mystical dimensions of consciousness, that usually lie outside the boundaries of personal or scientific interest. He pursued a life-long interest in the phenomena of sub-liminal consciousness, or "exceptional mental states", including those found in hypnotism, automatisms (e.g. somnambulism), hysteria, multiple personality, demoniacal possession, witchcraft, degeneration and genius. James's interest in unusual states of consciousness led him to experiment with nitrous oxide, or "laughing gas" as it was then known, an experience that reinforced his understanding of transrational states of consciousness. He wrote that the conclusion he drew from these early "psychedelic" experiences was "that our normal waking consciousness, rational consciousness as we call it, is but one special type of consciousness, while all about it, parted from it by the filmiest of screens, there lie potential forms of consciousness entirely different." (James, 1901/1958, p. 228)

James wrote this statement in his The Varieties of Religious Experience, probably his most influential book. In it he explored with great discernment and eloquence the nature and significance of mystical or "conversion" experiences, by which he meant not only a person's change from one religion to another, but the process of attaining a sense of unity and the sacred dimension of life. In my book The Unfolding Self I adopted James' empirical, comparative approach to the study of transformative experience -- delineating the basic archetypal patterns of psychospiritual transformation. The present collection of accounts of experiences with ayahuasca stands in the same tradition of empirical phenomenology.

It is only recently, in re-reading William James' writings on his philosophy of radical empiricism (James, 1912/1996) that I came to realize that this philosophy actually provides the epistemology of choice for the study of altered states of consciousness. Within the materialistic paradigm still ruling in scientific circles, any insights or learnings gained from dreams, trances, intuitions, mystical ecstasies or the like, would be seen as "purely subjective" and limited to those states, i.e. not having general applicability or "reality". The ASC (altered states of consciousness) paradigm is still considered marginal. The psychologist Charles Tart in an essay on "state-specific sciences" attempted to break the conceptual stranglehold of this paradigm by suggesting that observations made in a given state of consciousness could only be verified or replicated in that same state. This solution seems theoretically valid, but attended with practical difficulties.

William James started with the basic assumption of the empirical (which means "experience-based") approach: all knowledge is derived from experience. Die Erfahrung ist die Mutter der Wissenschaft as the German saying goes -- "experience is the mother of science". James writes:
I give the name of 'radical empiricism' to my Weltanschauung. ... To be radical
an empiricism must neither admit into its construction any element that is not directly experienced, nor exclude from them any element that is directly experienced. For such a philosophy, the relations that connect experiences must themselves be experienced relations, and any kind of relation experienced must be accounted as 'real' as anything else in the system. (James, 1912/1996, p. 42)

This view can provide a philosophical foundation for a scientific psychology of consciousness. All knowledge must be based on observation, i.e. experience; so far this view coincides with the empiricism of the natural and social sciences. It's the second statement that is truly 'radical' and that explains why James included religious and paranormal experiences in his investigations. The experiences in modified states of consciousness are currently excluded from materialistic, reductionistic science. They would not be excluded in a radical empiricism. 



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