This paper argues where the dimensions emerge from. It's a fundamental paradigm shift in our view of the universe.We argue and demonstate that dimensional structure is derived from a single self-referential axiom. The equation σ = 1/(1+σ), whose positive solution is φ = (1+√5)/2, generates dimensions through a process termed sublimation: φ changes its mode of expression from number (1D) to shape (2D) to solid (3D) to polytope (4D) to tensor (8D, via E₈) to eigenvalue (∞D, via the fine structure constant). Each dimensional transition is forced by a geometric or algebraic residual that the previous dimension cannot resolve. Five-fold rotation (from φ = 2cos(π/5)) requires a plane. The angular deficit of three pentagons at a vertex (36° = π/5) forces folding into the third dimension. The binary icosahedral group acting on quaternions (Frobenius 1878) forces the fourth. The gap at dimensions 5–7 is the model's strongest structural prediction: no new algebraic threshold exists, so no dimension is generated. At dimension 8, Galois conjugation in ℚ(√5) pairs 4-vectors with their conjugates, producing E₈. The paper proves that φ is the unique algebraic unit combining class-number-1 arithmetic with a parameter-free self-referential origin. The sublimation pattern is falsifiable and makes specific predictions about which dimensions carry physical content. Programme results cited with zero free parameters: the fine structure constant α⁻¹ = 137.035999207 (0.05σ from Morel et al. 2020, with 81,225-formula ablation confirming uniqueness); the cosmological constant log₁₀(ρ_Λ) = −122.951; the gravitational constant via mass-chain closure; the Higgs quartic λ = 2φ/5² (0.045% match); all four PMNS neutrino mixing parameters (all within 0.4σ of NuFIT 5.3, with five kill conditions testable by JUNO, DUNE, and Hyper-Kamiokande); and all 26 Standard Model parameters. Part of the Pentagon Physics programme. ORCID: 0009-0009-6175-4408. Keywords: dimensional emergence, sublimation, pentagon geometry, E₈, fine structure constant, Pentagon Physics