Rupert Spira

What Is Consciousness? Spira, Kastrup and Koch (2021)

Updated 2026-06-20

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Overview

What Is Consciousness? - Rupert Spira, Bernardo Kastrup and Christof KochYouTube

On 12 November 2021, the Oxford Psychedelic Society hosted a three-way debate that brought two of the most articulate defenders of idealism — Rupert Spira and Bernardo Kastrup — into direct conversation with Christof Koch, one of the foremost neuroscientists of consciousness and the principal developer of Integrated Information Theory (IIT). The exchange was later released as Episode 49 of the Rupert Spira Podcast on 6 September 2022.

The event is notable not as a contest of fixed positions but as a genuine investigation: three thinkers who have spent decades attending carefully to the nature of experience, working from different starting points, discovering where their maps converge and where they do not. Kastrup himself later described it as an "adversarial debate" — yet noted that on reflection the participants had sharper disagreements going in than the conversation actually revealed.

The Three Positions

Each speaker opened with a two-minute statement that set the frame for everything that followed.

Koch grounded his account in what he called the elatic principle: for something to exist it must exert or be subject to causal power. On this basis, IIT identifies consciousness with the maximally irreducible intrinsic causal-effect structure of a system — quantified by the measure phi (Φ). Only the system that is the maximum of integrated causal power "exists for itself"; everything else, from galaxies to crowds, is in his phrase mere "dust" from an ontological standpoint. This is a precise and in some ways radical claim: consciousness is not produced by complexity in general but by a specific kind of self-referential causal organisation.

Kastrup described himself as a "non-romantic extreme reductionist" — meaning he takes reductionism seriously enough to carry it all the way, reducing everything to one thing rather than stopping at matter. That one thing is mind: not any individual mind, but an objective, transpersonal mental process that presents itself to observation as the physical universe. Physicality, on his account, is a "dashboard of instruments" — a cognitive representation shaped by evolutionary pressures — not the underlying reality. He was careful to distinguish this from panpsychism, which he argued makes incoherent assumptions from a physics standpoint.

Spira offered the dream analogy that has become central to his teaching. A mind asleep in one city dreams of a separate world made of matter, from the standpoint of a seemingly independent subject within that world. On waking, the dreamed world is recognised as the activity of one mind. Spira's suggestion is that this is not merely an analogy: universal Consciousness localises itself as each sentient being, and from that localised vantage point its own activity appears as a universe of matter outside mind. He defined consciousness as that within which all experience appears, that by which all experience is known, and — his stronger claim — that out of which all experience is made.

The Main Lines of Dispute

Phenomenal consciousness and the problem of measurement

The sharpest exchange concerned what it means to measure consciousness. Koch argued that IIT provides a principled answer: phi is a quantity that can in principle be computed for any system, distinguishing genuinely conscious systems from what he called "mere aggregates" like galaxies or the internet. He illustrated this with a thought experiment in which two brains are gradually linked neuron by neuron until the integrated information across them exceeds that of either alone — at which point, IIT predicts, there is one unified experience rather than two.

Kastrup's counterpoint was methodological rather than purely philosophical. He accepted IIT's internal logic but pressed on what its experimental confirmation actually measures. The empirical basis for phi, he noted, depends on subjective reports — and a subject can only report what it both experiences and knows it is experiencing. What the experiments may actually be tracking, he suggested, is not phenomenal consciousness as such but a higher-order capacity to know that one is having experiences (what philosophers call metaconsciousness). Phenomenal consciousness and metaconsciousness can come apart — and when they do, the neuro-correlates being measured belong to the latter, not the former.

Koch responded that IIT does not build in any requirement for self-awareness: many of our richest conscious moments involve no sense of self at all. The deep-sleep and anaesthesia cases were contested from both sides. Koch cited the clinical evidence — flatline EEG states in which patients later report no experience — as grounds for confidence that consciousness genuinely ceases. Kastrup pointed to research suggesting that apparent unconsciousness may often be an inability to form memory or to report, rather than an absence of experience, and mentioned near-death case studies as at least suggestive of consciousness during states of no measurable brain activity.

Spira's contribution to this thread was characteristically direct. He invited Koch — mid-debate — to pause and notice the simple fact of being aware, then to try to describe that awareness without referring to any thought, sensation, or perception. Koch answered that awareness felt "like being alive." Spira's point was not to score a rhetorical point but to illustrate the distinction his whole teaching rests on: the content of consciousness (colours, pains, memories) is what IIT and neuroscience study; the nature of consciousness — pure, contentless knowing — is what remains when attention is turned back on itself, and it discloses nothing that could be measured by phi or confirmed by fMRI.

The brain as generator versus the brain as image

Running beneath the measurement debate was a deeper ontological divide about what the brain is doing. Koch's framing — the brain generates or produces consciousness — was challenged by Kastrup with a direct inversion: the brain does not generate consciousness; it is what certain conscious activity looks like when observed from outside, across what he called a dissociative boundary. Spira used the image of flame and combustion: flames do not generate combustion, they are what combustion looks like. On this view, all the correlations between brain states and conscious states that neuroscience has established over 150 years are exactly what idealism would predict — and they carry no ontological implication that brain-stuff produces mind-stuff.

Koch acknowledged the force of this as an interpretation, while pressing for experimental distinguishability: what would a test look like that could decide between "brain generates consciousness" and "brain is the image of conscious activity"? This is the question the debate left productively open.

The universe and consciousness: inside out

An audience question prompted one of the debate's most vivid exchanges. Asked whether "we are the consciousness of the universe" and whether our death would diminish it, Spira offered a reframing that runs throughout his teaching: a person does not have consciousness, and the universe does not have consciousness — consciousness is the primary reality, and both persons and universe are how its activity appears from localised standpoints. Kastrup endorsed this framing almost word for word: "a person doesn't have consciousness, the universe doesn't have consciousness... only consciousness is conscious, and everything is a modulation of that."

Koch engaged honestly with the difference in starting points: IIT begins from a premise of fragmentation — elementary systems that can integrate information — and builds upward. Spira and Kastrup begin from an undivided field of awareness and ask how the appearance of separate subjects arises (Kastrup's term: dissociation; Spira's: localisation). The two approaches generate the same landscape in reverse.

Psychedelics: what they do and do not reveal

The final major theme arose from the Oxford Psychedelic Society context. All three speakers took psychedelics seriously as data while remaining cautious about interpretive overreach.

Koch noted that high-dose experiences demonstrate conclusively that the sense of self is not essential to consciousness — a point IIT also supports. He was more cautious about grand metaphysical conclusions drawn from the content of unusual states.

Kastrup argued that the psychedelic effect on the brain — reductions of activity, particularly in the default mode network and other inhibitory regions, without compensatory increases elsewhere — sits more naturally in an idealist-dissociation framework than in a generation framework. If psychedelics impair the very mechanism that produces the illusion of a separate self, what is left is not less consciousness but more — consistent with the "dissolution of dissociation" that his model predicts.

Spira's position was more restrained and, from his teaching standpoint, precise: psychedelics expand the content of consciousness, sometimes dramatically, but they do not by themselves reveal the nature of consciousness. That requires turning attention from content toward the knowing itself. He acknowledged, when asked by an audience member who had come to his work through psychedelic experiences, that such experiences can powerfully loosen the grip of the separate-self assumption and open a person to the self-inquiry that is his method's starting point.

Convergence and Remaining Distance

What the debate ultimately demonstrated was something Kastrup noted in retrospect: the apparent distance between the positions was considerably greater at the outset than it proved to be once the terms were carefully examined. Koch's insistence that consciousness "exists for itself" — intrinsically, not merely in relation to an external observer — is not far from Spira's claim that awareness alone is self-luminous. Where Koch and the idealists genuinely diverge is on the question of how individual conscious subjects arise from or relate to whatever is ultimately real.

For Spira, that question is answered not by theory but by investigation: the separate subject, when looked for directly, cannot be found as an independent entity. What remains is the awareness that was always already there — not a product of neural integration but the ground from which the investigation itself proceeds.

For readers of this wiki, the debate is worth approaching less as a conflict to be resolved than as a living map of where contemplative recognition and consciousness science currently meet, and where they still need to find each other.

Bernardo Kastrup and Rupert Spira: Argument Meets Recognition

Consciousness Is Fundamental

The Consciousness-First Landscape