The chapter's convergence is strongest where its lines truly separate. Stage 1 pressure-tests □◇C but does not rederive proposition-wise modal invariance without T1. Stage 2 reaches □(T∧S∧Φ) at role-resolution through several S5-free construction and closure arguments. Stage 3 identifies Reality with that necessary role-level structure through maximality and the residue argument, with role-semantics reinforcing. The Grounding Trilemma independently excludes an external ground of Nature, but it reaches the full identity only together with maximality or the residue closure.

This section gathers those results, names their exact dependencies, separates role from type, and lets the S5 Bottleneck confirm from above what the S5-free lines establish from below. Robustness here means that every shared joint is visible and every conclusion is stated at the strength its lines actually carry.


- [3.5.1 Overdetermining the Spine](<3.5.1 Overdetermining the Spine.md>)
- [3.5.2 Robustness](<3.5.2 Robustness.md>)
- [3.5.3 The Closed Seam](<3.5.3 The Closed Seam.md>)
- [3.5.4 S5 Lives Upstream](<3.5.4 S5 Lives Upstream.md>)
- [3.5.5 The S5 Bottleneck Reductio](<3.5.5 The S5 Bottleneck Reductio.md>)


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← [3.4.5 Downstream of the Seal](<3.4.5 Downstream of the Seal.md>) | [3.5.1 Overdetermining the Spine](<3.5.1 Overdetermining the Spine.md>) →
