The Five Axioms of Consciousness

In the AI Story

The axiomatic approach distinguishes IIT from virtually every other theory of consciousness. Most theories begin with mechanism (the brain, computation, information processing) and try to derive or explain experience. IIT begins with experience itself — the phenomenology — and works backward to the physical structure that must support it. The axioms are not hypotheses to be tested against behavior; they are starting assumptions derived from what cannot be denied about the character of experience.

Existence is the Cartesian ground: the one thing that cannot be doubted is that experience is happening. Whether the experience accurately represents external reality, whether the self that has it is what it seems to be, whether anything outside experience exists at all — all these can be questioned. But the existence of the experience itself is the condition of the questioning.

Composition captures the structured character of experience. When one sees a red triangle on a blue background, the experience contains color, shape, spatial relationship — but these are not separate items thrown together. They are components of an integrated whole. Experience is always compositional: always multiple phenomenal distinctions bound together into a single field.

Information is the specificity of each experience. Seeing a red triangle is different from seeing a blue circle, different from hearing a C-sharp, different from the smell of coffee. Each experience is what it is by virtue of being different from the vast space of experiences it could have been. This is information in the technical sense — differentiation among possibilities.

Integration captures the unity of experience. One cannot have half an experience. The visual field does not split into a left half and a right half that are independently conscious. The redness and the triangularity and the spatial location are experienced as a single thing, by a single subject. Integration is not aggregation — it is the irreducible unity of phenomenal experience.

Exclusion captures the definiteness of experience. At any given moment, one has this experience and not that one. The experience has specific borders, specific contents, specific grain. It does not blur into other experiences; it does not nest within higher-level experiences or split into lower-level ones. Each conscious moment is singular.

Key Ideas

Phenomenological priority. Start with what is undeniable about experience and derive the physics.

Five necessary properties. Existence, composition, information, integration, exclusion — each captures a different aspect of phenomenal experience.

Derivation of postulates. Each axiom generates a corresponding requirement on physical causal structure, connecting phenomenology to mechanism.

Irreducibility. The axioms are not hypotheses to be empirically tested but starting points derived from the character of experience itself.

Foundation for substrate-independence. Because the axioms describe experience independently of any specific substrate, the derived postulates apply to any physical system.