Version 4.0 — April 2026. This version extends the architectural specification of the three engines in Section 5 with four additions: (1) the engines are situated within the neuro-symbolic AI research program, with the distinguishing claim that symbolic constraints are enforced within the attention mechanism itself rather than as post-hoc corrections on neural outputs; (2) the set/class distinction of NBG set theory is introduced as an architectural analogy, framing the transformer as a set-level extensional architecture and the engines as introducing class-level intensional membership conditions for valid generative states; (3) the router and attractor are clarified as functionally integrated within a single unified operation rather than sequential steps; and (4) the RLPF training methodology is reframed in cybernetic terms as a positive attractor encoding a goal state structurally, contrasted with RLHF as a negative attractor. The Ma et al. citation in Section 1 has been precision-corrected to accurately represent their benchmark validity finding. The stochastic probe concept in Section 3.2 has been attributed to its correct intellectual lineage. The current generation of Large Language Models has compressed the entire symbolic output of human civilization into a single synthesizable architecture. What it has not accomplished, and what no amount of scaling will supply, is the structural foundation that makes symbolic cognition safe, coherent, and genuinely useful in a physical world. This structural absence, the Inversion Error, is a failure of integration between the high-level symbolic reasoning of the Transformer and the foundational enactive constraints of the physical world. It manifests as three discrete, reproducible, and diagnosable failure modes: Continuity, Gravity and Physics, and Reversibility of Thought. A structured pilot study, the Spaghetti Table Protocol, administered across three leading multimodal systems produces an aggregate score of 4 out of a possible 30 on a three-pillar diagnostic rubric, confirming the Inversion Error as a reproducible Class Failure of current transformer architectures rather than a model-specific artifact. The Parametric AGI framework proposes three formally specifiable, sparsely-gated Attention Mechanism modifications to the Transformer architecture: the Somatic Engine, the Gravity Engine, and the Episodic Buffer Engine. Situated within the neuro-symbolic AI research program, the engines encode symbolic physical constraints as differentiable priors within the attention mechanism itself, enforced during the forward pass rather than as post-hoc corrections, introducing class-level intensional constraints into what is currently a set-level extensional architecture. Trained through Reinforcement Learning from Physical Feedback (RLPF) rather than human preference ratings, they address the structural gap between statistical pattern and physical constraint. The framework is grounded in abductive reasoning and AI system design understood as theory-building in Peter Naur's sense: a structural condition diagnosed from the socio-technical designer's vantage point, visible from outside the engineering system and invisible from within. This paper is simultaneously a diagnostic contribution, a solution architecture proposal, and a collaboration invitation to the mathematical and ML research communities for formal engine specification, to the AI safety research community for corrigibility and inner alignment engagement, and to foundation model and world model development teams pursuing physical grounding for development-level access to active training environments.