Grammar, Manifold, and Ontological Grounding: A Response to Cabannas and Silva (2026)

A formal response to the dialogue paper "The Modal Discipline of Symbolic Discovery" (Cabannas and Silva, DOI: 10.5281/zenodo.19519487), which offered a systematic analysis of PIR-JEPA in the framework of the Theory of Objectivity (TO). This response accepts the central distinction between epistemological-operational and ontological-modal levels, and advances the dialogue on three specific points: (1) The over-diffusion phenomenon discovered in PIR-JEPA v2 — where Langevin DR drops from 100% at T=500 to 60% at T=1000 — provides an empirical analogue to TO's principle of modal discipline: unconstrained formal search past the modal neighbourhood of a target law reduces rather than increases discovery. (2) The Grammar-Loss Separation principle is restated in modal language: grammar coverage failure is modal impossibility; loss function failure is epistemic failure. These are orthogonal, as TO itself distinguishes impossibility of access from failure of recognition. (3) The Δs hidden physics sensitivity metric is proposed as a step toward the observational triangulation TO's Fifth Absolute Truth demands — two independent symbolic hypotheses validated against the same observational data. A four-point programme of continued dialogue is proposed: galaxy rotation curves (SPARC), over-diffusion basin geometry, modal logic formulation of Grammar-Loss Separation, and PIR-LIGO. Related records: PIR-JEPA v2 (DOI: 10.5281/zenodo.19477508), Cabannas and Silva dialogue (DOI: 10.5281/zenodo.19519487), PIR Architecture v3 (DOI: 10.5281/zenodo.19428230).