The Perceptual Horizon Error: Gratitude, Adversarial Narrowing, and the Preservation of Possibility in Human and Artificial Intelligence

Bismillah. A conceptual and methodological research preprint introducing the Perceptual Horizon Error -- the mistaken treatment of presently accessible possibilities as the complete space of outcomes. Identifies a dual-sided failure mode: the target mistakes restricted options for completeness, while the adversary assumes its restriction strategy will persist across future conditions. Proposes the Perceptual Horizon Resilience Protocol (PHRP), a six-phase EESS companion workflow, and five falsifiable hypotheses (H1--H5) with a proposed 2x2 factorial pilot design. No empirical results are claimed. Cross-model review by Claude Opus 4.6; nine findings dispositioned in the appendix. Bismillah.