The Mark as the Limit of the Real

Any entity defined as existing outside spacetime is, by that very definition, inaccessible to any mark. The impossibility is not empirical but structural: spacetime constitutes the condition of possibility for inscription, and without inscription there is no fact. The distinction between the real (material dynamics independent of the symbolic), the concrete (the mark as an irreversible difference inscribed on a durable, addressable physical substrate), and theory (the symbolic organisation of predictions concerning possible marks) is a substantive ontological distinction: the criterion by which what exists is separated from what is merely postulated. Applied to Ruth Kastner's Relativistic Transactional Interpretation and to Everett's many-worlds interpretation, this criterion identifies, in both cases, the same structural property: immunity to refutation by domain definition. The property is formal and content-independent: it applies to any postulation that situates its central entity outside the domain of inscription, regardless of the degree of sophistication or predictive utility of the formulation. A thesis that is irrefutable by construction does not produce knowledge; it produces belief. Immanentist materialism is not one presupposition among others: it is the minimal condition under which inquiry distinguishes itself from speculation.