معارف منطقی

Symbolic formalization of philosophical arguments using the language of modern logic can contribute to greater clarity, conceptual precision, and more systematic evaluation of philosophical problems. Through explicit symbolization and rigorous inferential rules, modern logic reduces ambiguity and reconstructs philosophical reasoning in a structured and disciplined manner. The third stage of Asfār begins with Mullā Ṣadrā’s formulation of the Proof of the Truthful (Burhān al-Ṣiddīqīn), in which the necessity and self-sufficiency of pure existence are established. Standard Frege–Russell predicate logic lacks the resources required for an adequate analysis of the ontological notions involved in this proof. This limitation stems primarily from the fact that, in ontological inquiry, the domain of existence must be narrower than the domain of discourse, allowing existence and non-existence to be meaningfully predicated of objects. Moreover, classical logic provides no formal mechanism for representing gradational (tashkīkī) predicates. In this study, by introducing existential predicate logic for ontological analysis and employing the expressive capacities of fuzzy logic to formalize gradational predicates, the conceptual and propositional foundations of the proof are examined, and a more precise reconstruction of its argumentative structure is presented.