ora-0063
4.3 The five-obligation test
A candidate categorification of a core system should satisfy five obligations.
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- Restriction.
The doctrine defines a proper, non-vacuous subcategory of possible models.
- Invariance.
Presentation changes that preserve the hypothesized competence induce declared equivalences rather than arbitrary retraining.
- Composition.
Local capacities have typed interfaces and coherent overlaps with other core systems.
- Identification.
The restricted hypothesis class removes ambiguities that cannot be removed from the same evidence under a weaker prior.
- Repair.
Violations distinguish a mistaken realization from evidence that calls the doctrine itself into question.
These are joint obligations. A tiny hypothesis class may make identification easy by stipulation while misrepresenting the observed invariances. A very expressive category may fit every transcript while excluding nothing. A collection of accurate fragment models may still fail to explain how number, space, objects, agents, and language become one world.
A categorical prior earns empirical meaning by the alternatives it rules out, the equivalences it preserves, and the cross-system predictions it forces. Mere encodability is not evidence for categorical core knowledge.