Altered States of Consciousness
The science of consciousness awakens
Description
For most of the twentieth century, if a psychologist wanted to keep a respectable job, there was one word to avoid: consciousness. The behaviorists who dominated American psychology from the 1910s onward had made a decision that looked like housekeeping. Anything you could not measure from the outside — a feeling, an image, the texture of a dream — was not fit material for a science. What a person reported about their own mind was, at best, unreliable data. At worst, it was a distraction. So the inner life quietly left the building, and the discipline spent decades studying rats in mazes and reaction times, confident it had traded superstition for rigor.
By the late 1960s that confidence was fraying. Millions of people were meditating, taking psychedelics, practicing hypnosis, keeping dream journals, and reporting experiences that did not fit anywhere in the official picture of the mind. The states were real to the people having them, they were widespread, and psychology had almost nothing serious to say about them. Into that gap stepped Charles Tart, a psychologist who in 1969 gathered the scattered research into a single volume, Altered States of Consciousness, and made a quiet but radical claim: these states could be studied, carefully and empirically, without pretending they were not happening.
The book was less a manifesto than an assembly. Tart collected work on dreaming, hypnosis, meditation, drug-induced states and more, and put it under one roof to show that a science of consciousness was not a contradiction in terms. What held the collection together was a conviction that the ordinary waking mind is one arrangement among several, not the only one worth taking seriously. That conviction is where the story begins.
The question we’re asking : Can the experiences we have inside our own heads become the material of a real science, rather than something psychology politely ignores?What we’ll see : How a discipline that banished the inner life found a way to bring it back, and what changes once we stop treating ordinary waking awareness as the only mind worth studying.
Table of contents
01Chapter 1 — A science that lost its nerve
The exile of consciousness from psychology was not an accident. In 1913, John Watson published the founding argument of behaviorism, and the case was blunt: introspection had produced fifty years of quarrels and no cumulative knowledge. Two people looked inward, described what they found, and disagreed with no way to settle the matter. A science needs public data — things any competent observer can check. Behavior is public. Private experience is not. So the field agreed, more or less, to talk about what organisms do and to stop talking about what they feel.
The bargain paid off in some ways. Behaviorism produced solid findings about learning and conditioning, and it gave psychology the outward look of a hard science. But the cost was that a whole continent of human life became unmentionable. Dreams, which everyone has, were treated as noise. Mystical experiences, which recur across every culture, were left to theology. The states people entered under hypnosis or after fasting or in deep prayer were either ignored or quietly filed under pathology, as if anything unusual about the mind must be a malfunction.
02Chapter 2 — The map has more than one territory
At the center of the book is a deceptively simple idea. What we call ordinary waking consciousness is not the mind's natural resting state, revealed once distractions clear away. It is a specific configuration — a particular way that attention, memory, perception, emotion and the sense of time are wired together and held in place. Tart's word for this was a discrete state of consciousness: a whole system that stays stable within limits, then, under the right pressure, reorganizes into a different stable pattern. Sleep is the obvious example. Waking is another. But there are more.
The pressure that triggers a shift is what Tart called an induction. A monotonous chant, a fixed gaze, a dose of a psychoactive substance, sensory deprivation, controlled breathing, sleep loss, intense grief — each can loosen the ordinary arrangement enough for the system to fall into a new one. The important claim is that the new arrangement is not simply the old mind minus something, the way a drunk person is often described as a sober person with a few functions switched off. It is a different working configuration, with its own logic, its own way of handling time and self and meaning.
03Chapter 3 — How to study a state from the inside
The hardest problem Tart faced was the one that had scared psychology off in the first place: how do you study something that only shows up in private experience? His answer was not to abandon the outside measurements but to stop treating them as the whole story. Brain waves, heart rate, eye movements, drug dosages — all of it still matters. What Tart insisted on adding back was the disciplined report of the person actually in the state, trained to observe carefully and describe precisely rather than dismissed as a hopeless witness to their own mind.
The model he reached for was borrowed, in spirit, from the way any observational science handles a difficult subject. An astronomer does not distrust the telescope simply because looking is involved; the instrument is calibrated, the observer is trained, and observations are compared across many careful people. Tart argued that a person could become a trained observer of their own consciousness in the same way — learning to notice and report the shape of an experience without immediately explaining it away. Introspection had failed earlier not because it was impossible but because it had been done casually, by untrained observers with no shared method.
04Chapter 4 — Consciousness as a discipline in the making
Step back from the individual states and a larger stake comes into view. What Tart was really arguing for was the readmission of subjective experience as a legitimate object of science — and that is a claim about what science is allowed to be, not just about dreams and meditation. For half a century, the price of respectability in psychology had been silence about the very thing that makes a mind a mind: the fact that there is something it is like to be one. Studying consciousness scientifically meant deciding that the felt quality of experience was not embarrassing leftover data but the phenomenon itself.
This is why the book reads less like a set of results and more like the founding charter of a field that did not yet exist. Tart was assembling a discipline out of scattered pieces — sleep laboratories here, hypnosis researchers there, meditators and psychedelic chemists who barely spoke the same language — and insisting they were all working on one problem. The gathering was itself the argument. Put these researchers between two covers and it becomes hard to keep pretending that consciousness is not a coherent subject of inquiry.
05Conclusion
The mind that behaviorism had shown the door turned out to be difficult to keep out. By collecting the research on dreaming, hypnosis, meditation and drug states into one volume, Tart did something a single experiment could not have done: he made the case that these were not fringe curiosities but a single, studiable field. The waking state we treat as default was recast as one arrangement among several, each with its own logic, and each in principle open to careful investigation by observers trained to report what they actually experience.