The Infinite Principle establishes that whenever an option has unbounded upside and bounded downside, pursuing it is not just reasonable—it is mathematically required. Rooted in expected value theory, the principle proves that any decision meeting these conditions dominates all finite alternatives.

This paper derives the Infinite Principle rigorously, addresses key objections, and demonstrates its universal applicability across domains such as venture capital, existential risk mitigation, and technological innovation. Optimism, long considered a bias, emerges as the only rational stance in decisions where potential is limitless.

The conclusion is inescapable: when unbounded opportunity exists, rejecting it in favor of finite caution is a systematic error. Rejecting infinite potential is not caution—it is miscalculation. Rationality demands we embrace the infinite.