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Integrated Information Theory vs Kastrup’s Analytic Idealism

Integrated Information Theory (IIT) and Analytic Idealism, compared field by field from their entries in the Atlas.

At a glance

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Information Integrated Information Theory (IIT) Giulio Tononi, Christof Koch
Idealism Analytic Idealism Bernardo Kastrup

The claim

In brief
Integrated Information TheoryIIT is an original, radical model that proposes a definition for conscious experience and specifies which physical systems can possess it, starting from the phenomenology of consciousness (axioms). It translates these axioms into physical postulates based on intrinsic cause-effect power, featuring a mathematical measure Φ(Phi) to quantify a system's capacity for informational integration, which correlates with the degree of consciousness.
Kastrup’s Analytic IdealismAnalytic Idealism is a consciousness-only ontology asserting that phenomenal consciousness is fundamental, the singular primitive of reality. Everything else in nature, including the physical world and individual minds, is grounded in patterns of excitation or expressions of this spatially unbound cosmic consciousness.
What consciousness is
Integrated Information TheoryConsciousness is identified as a Φ-structure, a maximally reduced conceptual structure existing in 'qualia space'. An experience is identical to this conceptual structure, meaning its phenomenal properties correspond precisely to the physical properties of the cause-effect structure unfolded from the physical substrate of consciousness (PSC).
Kastrup’s Analytic IdealismConsciousness is identified as the singular, spatially unbound, fundamental ontological primitive (cosmic consciousness).

Big questions

Integrated Information TheoryNoKoch, a proponent, argues that consciousness is not computable. Digital computers have negligible integrated information (Φ(Phi)) due to hardware structure, meaning they can never be sentient, regardless of intelligence.
Kastrup’s Analytic IdealismNoKastrup suggests conscious AI is a fantasy, arguing that consciousness is not reducible to computation or information processing that current computers perform. Consciousness is tied to fundamental phenomenal reality, not hardware function.
Integrated Information TheoryUncertainIf phenomenal consciousness requires a radically new structure (like IIT's postulates), the potential permanence of these 'inscrutable things' cannot be rejected, leaving the possibility of survival open, even though IIT does not explicitly espouse life after death.
Kastrup’s Analytic IdealismLikelyBodily death is predicted to result in the cessation of the local boundary (dissociated alter), causing conscious inner life to expand back into the underlying universal consciousness. This is supported circumstantially by reports of near-death experiences (NDEs).
Integrated Information TheoryNoIf consciousness is a fundamental property tied to real cause-effect power, a digital simulation (uploading) would only create a 'perfect zombie'—an entity that acts like the original but lacks subjective consciousness—because the simulation is virtual, lacking the required real cause-effect power.
Kastrup’s Analytic IdealismNoConsciousness is not an algorithm or software program reducible to physical structure; therefore, uploading neural patterns (simulated continuation) would only result in a functional duplication ('deep fake') lacking true subjective experience.
Integrated Information TheoryUncertainWhile the measurement and analysis of consciousness do not convey ultimate meaning, the speculative nature and novelty of the innumerable nth dimensional conceptual structures (conscious percepts) warrants suspending judgment on ultimate meaning/purpose/value.
Kastrup’s Analytic IdealismCosmic/UltimateAs consciousness is ultimate reality, existence is fundamentally grounded in mind/awareness, intrinsically providing meaning and purpose rooted in the singular, fundamental consciousness.

Nature of mind

Ontology
Integrated Information TheoryIIT's fundamental ontology is the ontological primacy of phenomenal existence, based on an intrinsic powers view where what truly exists in physical terms are intrinsic entities capable of cause and effect. Koch notes that the theory insists consciousness must be incorporated into the basic description of reality at the rock-bottom level.
Kastrup’s Analytic IdealismIdealism (Modern analytic metaphysics)
Mind and body
Integrated Information TheoryIIT asserts an explanatory identity: an experience is identical to a Φ-structure. It contends that the conscious entity is the Φ-structure expressing its causal powers, not the neural substrate itself. This framework leaves no room for emergence or dualism.
Kastrup’s Analytic IdealismIndividual minds are dissociated alters of the cosmic consciousness. The inanimate physical world is the extrinsic view of thoughts and emotions within this universal consciousness, meaning a physical world independent of consciousness is a mistaken intellectual abstraction.
Fundamental or emergent
Integrated Information TheoryConsciousness is defined by intrinsic existence and characterized as belonging to the basic description of reality. The theory rejects emergence.
Kastrup’s Analytic IdealismPrimitive (Fundamental)
Qualia
Integrated Information TheoryDistinct conscious experiences are conceptual structures in a 'qualia space'. The qualitative feel (phenomenal properties) corresponds one-to-one to the physical properties of the maximally irreducible cause-effect structure, which is also called a quale.
Kastrup’s Analytic IdealismQualia are intrinsically real and fundamental, constituting patterns of excitation within the fundamental phenomenal consciousness.

How it works

Mechanism
Integrated Information TheoryThe core principle is Integrated Information (Φ(Phi)), which quantifies the system's irreducibility. The Exclusion Postulate ensures that only the maximally irreducible cause-effect structure (the Φ-structure) exists intrinsically, defining the boundaries and grain of consciousness.
Kastrup’s Analytic IdealismThe principle of dissociation, which localizes the unitary cosmic consciousness into seemingly isolated subjects (alters).
Where it is
Integrated Information TheoryConsciousness is not limited to biological brains. IIT predicts the conscious structure resides in the posterior cortex (occipital, parietal, and temporal cortices). Systems with maximally irreducible intrinsic cause-effect power possess consciousness.
Kastrup’s Analytic IdealismUbiquitous; consciousness is fundamental and spatially unbound. Individual conscious subjects are localized boundary conditions (dissociated alters).
What it does
Integrated Information TheoryConsciousness is identified as unfolded intrinsic causal power, which is the ability to effect change. Only this intrinsic entity (the Φ-structure) can cause, supporting the claim that true free will exists for systems with high Φ(Phi).
Kastrup’s Analytic IdealismCausation is grounded in consciousness itself. The inanimate world is the extrinsic manifestation of universal mentation, while the brain serves to constrain or mediate individual consciousness.

Evidence and criticism

Testability
Integrated Information TheoryIIT claims scientific testability, employing quantitative measurement. However, critics argue that the theory is not truly empirically tested, and its core predictions may be idiosyncratic.
Kastrup’s Analytic IdealismSpeculative/Conceptual. Testable primarily by demonstrating the incoherence or lack of parsimony of rival metaphysical theories and by predicting experiential outcomes in extreme states.
Tests so far
Integrated Information TheoryCalculating Φ(Phi) for specific neural networks (e.g., visual cortex).,Monitoring brain activity as subjects slip into anesthesia.,Adversarial collaboration experiments testing predictions about sustained activity in the posterior cortex.
Kastrup’s Analytic IdealismCites neuroimaging of psychedelic states (rich experience correlating with reduced brain activity) to critique physicalist theories.
Criticisms
Integrated Information TheoryThe theory faces criticism for anti-common sense predictions (imputing consciousness to simple objects). A public letter characterized IIT as 'pseudoscience'. Critics challenge that experiments test only idiosyncratic predictions and not the core metaphysical ideas. Chalmers noted the 'pseudoscience' label was disproportionate and caused vast collateral damage.
Kastrup’s Analytic IdealismThe main critical challenge is the 'decomposition problem': explaining how seemingly distinct phenomenal inner lives of subjects can arise within a fundamentally unitary phenomenal field. Also must reconcile the independence of the common external world from personal volition.

Sources

Key sources
Integrated Information Theory
  • From the phenomenology to the mechanisms of consciousness: integrated information theory 3.0, Oizumi, Albantakis, Tononi (2014)
  • Consciousness: here, there and everywhere?, Tononi and Koch (2015)
  • Only what exists can cause: an intrinsic powers view of free will, Tononi et al. (2022)
Kastrup’s Analytic Idealism
  • An ontological solution to the mind-body problem (2017)
  • The universe in consciousness (2018)
  • Analytic Idealism: A Consciousness-Only Ontology, Dissertation (2019)

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