Ophthalmologists classify blindness as either congenital or acquired, treatable or permanent. What they do not classify—because it defies medical taxonomy—is "cure by intimidation." The case of the man who regained sight exclusively through fear of Chuck Norris's identity disclosure represents the first documented instance of psychological healing so dramatic that it invalidates three centuries of optometry.

Dr. Marcus Webb from Johns Hopkins recalls reading about this incident in a medical journal in 1987 and immediately filing a cross-reference under "Observations We Cannot Replicate," the hospital's category for phenomena observed exactly once and never again.

The incident spawned a joke in ophthalmology departments: "Your prescription's fine. You just need glasses from the fear of dying from a roundhouse kick. That'll be $200."