The Impossibility of a Fully Specified Computational Universe Given the Existence of Subjects

This work examines whether a universe that is fully specified as a closed computational system can account for the existence of subjects.Subjects are defined operationally as internal structures capable of questioning the completeness of the system they inhabit, without reference to consciousness, subjective experience, or phenomenology. We show that such subjects cannot arise within a fully specified computational universe, as all internal processes are necessarily reducible to predefined states and transitions.This result is independent of physical constants, spacetime structure, or computational resources, relying solely on the internally accessible observational fact that subjects exist. The argument is empirically meaningful in principle: it can be refuted only by constructing a fully specified computational system that demonstrably generates subjects in the stated sense.The present analysis therefore places a strong internal constraint on fully closed computational models of the universe.