Existential Realism on Trial: A Series of Critical Q&A Stress-Tests

This paper presents a structured critical dialogue examining Existential Realism (ER), a temporal ontology that distinguishes between existence and reality. According to ER, only present entities exist in the strict sense of present instantiation, while past events and structured future possibilities remain real as parts of the world's causal and modal structure. The dialogue places ER in conversation with several competing perspectives, including presentism, eternalism, and structuralist interpretations of spacetime.Through an exchange between a Critic and a Defender, the discussion explores a range of pressure points for the theory: the coherence of the existence–reality distinction, the grounding of past-tense truths and truthmakers, the status of causal relations across time, the treatment of modal structure and future possibilities, and the compatibility of ER with relativistic spacetime. The dialogue also considers whether ER offers a genuine ontological alternative to established views or whether its claims ultimately collapse into either presentism or a variant of block ontology.Rather than delivering a final verdict, the paper aims to clarify the conceptual commitments of ER and to expose both its potential explanatory advantages and its unresolved challenges. By articulating these tensions in dialogue form, the paper seeks to sharpen the philosophical contours of the theory and identify areas requiring further development.