**[[167_O1_Information-Primitive|O1]] (Information Primitive):** Information is an ontological primitive—it cannot be reduced to or derived from anything more fundamental. Information is not merely descriptive but constitutive of reality.
The substrate itself is describable only through its informational properties. What is an electron? A set of quantum numbers (information). What is a field? A function mapping spacetime points to values (information). The substrate IS information; saying information needs a substrate confuses levels of description. The substrate "carrying" information is itself information at a different level. It's information all the way down.
Landauer's insight that information has physical cost (kT ln 2 per bit erased) supports [[167_O1_Information-Primitive|O1]], not contradicts it. If information were merely abstract, it would have no physical cost. Landauer proves information is physical—but Wheeler extends this: if information is physical, and all physics reduces to informational properties, then information is the physical primitive. Landauer and Wheeler are complementary, not contradictory.
[[167_O1_Information-Primitive|O1]] explicitly asserts this is not a category mistake but a category identification. The epistemological/ontological distinction assumes matter exists independently of its informational description. But quantum mechanics shows measurement (information extraction) is constitutive. There is no "matter" outside of its informational characterization. The categories converge because reality is informational.
Digital physics (Zuse, Fredkin, Wolfram) is one version of informational ontology, but [[167_O1_Information-Primitive|O1]] doesn't require it. [[167_O1_Information-Primitive|O1]] requires only that information is primitive—not that reality is a cellular automaton. Quantum information theory is mainstream and supports informational primitiveness. AdS/CFT holography is mainstream and encodes gravity as boundary information. The holographic principle is mainstream and bounds entropy by surface area (information). [[003_A1.3_Information-Primacy|Information primacy]] is increasingly standard, not fringe.
[[167_O1_Information-Primitive|O1]] declares information primitive precisely to stop the regress. Primitives are termination points—you don't ask "what is X made of?" when X is primitive. The question "where did information come from?" assumes information is derivative; [[167_O1_Information-Primitive|O1]] denies this. Information exists necessarily with existence ([[161_P0_Origin-Stage|P0]]) and consciousness ([[162_P1_Consciousness-Stage|P1]]). The question is like asking "where did existence come from?"—it's category confusion.
Information is Physical:
Erasing one bit costs at least k_B T \ln 2 energy. This is not metaphor; it's thermodynamics.
Experimental Verification:
Bérut et al. (2012): Colloidal particle in double-well potential. Erasure measured at Landauer bound. Information has measurable physical cost.
Implication: If information has physical cost, information is physical. If information is physical and all physics reduces to information, information is the physical primitive.
Definition:
Uniqueness Theorem (Khinchin):
Shannon entropy is the unique measure satisfying:
1. Continuity
2. Monotonicity (more equiprobable outcomes = more entropy)
3. Additivity for independent sources
4. Recursivity (chain rule)
This uniqueness suggests Shannon entropy captures something fundamental—not arbitrary choice but unique characterization of information.