The Optional Alterity Hypothesis: From the F-117 to the Perfect Mirror — Algorithmic Personalization and the Filtering of Human Difference

This paper proposes a conceptual shift in the understanding of algorithmic personalization: contemporary recommendation systems do not primarily filter information — they filter the perceived identity of individuals within the user's social graph. The Optional Alterity Hypothesis holds that engagement-optimized ranking selectively surfaces the compatible dimensions of known contacts while amplifying the most adversarial fragments of perceived opponents. The result is not a world of false information but a world of real people rendered proportionally unrecognizable. The paper traces the causal chain linking algorithmic architecture to cognitive vulnerability, to the construction of individually calibrated adversarial archetypes, to a form of social isolation termed presence loneliness: the physiological deficit of co-regulation that accumulates when digital connectivity displaces physical proximity without triggering the nervous system's social baseline alarm. The argument distinguishes three causal layers: deliberate commercial intent, opportunistic political capture, and systemic emergence. A structured claims ledger explicitly distinguishes empirical observations, theoretical hypotheses, and extrapolations. First formulated 2017. Updated 2026. También disponible en español / Also available in Spanish: La Hipótesis de la Alteridad Opcional: Del F-117 al espejo perfecto