Metaphysical Investigations

The argument from frustration of purpose (burhān naqḍ al-gharaḍ) is a key rational proof in Imāmī theology for establishing the absolute infallibility of the prophets. Grounded in divine wisdom and the purposiveness of God’s actions, it holds that the full realization of the prophetic mission—comprehensive guidance and human felicity—requires absolute infallibility; any possibility of error or sin would weaken public trust and compromise effective guidance. In Imāmī thought, infallibility is understood as extrinsic impossibility (imtināʿ bi’l-ghayr): while the prophet retains free will, he lacks any effective motive to sin due to presentational knowledge, profound love for God, and a firmly rooted moral disposition.

Using an analytical–critical approach and drawing on classical Imāmī theological sources and contemporary philosophical works, this study examines major objections to the argument, including the sufficiency of relative infallibility, appeals to the principle of “greater good and lesser evil,” analogies between prophets and religious authorities, and the Humean objection concerning the inference of an “ought” from an “is.” It argues that these critiques result from conflating partial with complete realization of divine purpose, overlooking the essential distinction between prophets and other religious agents, and misconstruing the relationship between divine knowledge, will, and power. The study concludes that divine wisdom requires prophets to be immune, throughout their entire lives, from all intentional and unintentional error and forgetfulness in receiving and conveying revelation as well as in personal and social conduct.