Closure Before Bearers: Bearer-Neutral Specification of Closure-Class Structure

Bearers track closure classes; closure classes do not track bearers. This inversion is the substantive claim the present paper defends, and its grounds are structural: the framework operates at the admissibility stratum, characterizing what closure formation can produce; bearers are realization-stratum products of closure formation; the partition between class members and non-members is a consequence of closure rather than a feature of the framework's structural commitments. The seed-field framework (Thomas 2026a) characterizes closure-class formation through structural conditions on admissibility analysis, but the relation between class C and the conditions characterizing it is left underspecified in that paper alone; the present paper specifies the relation by establishing where the framework's apparatus operates and what it characterizes. The structural conditions S_C are specified through five formal families — eigenstructure conditions on the linearized closure-formation operator, rank conditions on the eigenmode's projection across maintenance-cost surfaces, graph-theoretic support conditions on the correction graph, scaling conditions on the cost functional, and bound conditions on the temporal ratios — each statable on the admissibility analysis without reference to bearer-types. Closure classes are equivalence classes of closures whose admissible modes satisfy a given S_C, with class identity attaching to constraint-preserving dynamical possibility structure rather than to recognized bearer-type. The apparatus is read correctly across five common questions through the bearers-track-classes inversion, the distinction among definitional, discovery, and naming dependence, the Platonism disclaimer, the demonstration that the apparatus extends to hypothetical and uninstantiated classes, and the labels-versus-apparatus distinction. The methodological precedent is the universality-class apparatus in critical phenomena, which operates at the class stratum upstream of where phase boundaries are realized. The consequence framing licenses cross-substrate predictions: substrates satisfying S_C in basin completion produce closure with the structural features S_C characterizes, regardless of substrate type. The framework's empirical commitments are preserved with this addition; the architectural foundation is clarified.