This preprint proposes a shift in the ontological reading of general relativity: rather than treating spacetime as the stage on which matter acts, it asks what follows if certain configurations of spacetime curvature are matter. From this single shift, five propositions follow with internal consistency — describing ordinary matter, dark matter, gravity, dark energy, and the particle spectrum as different expressions of a single underlying structure called spacetime condensation. The paper is explicit about what it is and what it is not. It does not present a new formal theory or derive new equations. It presents a conceptual chain that is internally consistent, grounded in established results, and supported by the independent convergence of several existing theoretical programs — none of which was developed with the others in mind. That convergence is identified and named, and four open questions are formulated with sufficient precision to constitute a research agenda.Intended for theoretical physicists, mathematical physicists, and philosophers of physics interested in the ontological foundations of spacetime and the unification of gravity with quantum theory.