General Paresis of the Insane is a kind of paralytic dementia which affects the brain and nervous system, resulting in seizures and other muscular reflex abnormalities. At the time, doctors did not know that GPI was caused by syphilitic infection. Here, Buck Mulligan refers to GPI as Genera Paralysis of the Insane, when it is not "Paralysis," but "Paresis." Despite his medical background, he is still ignorant of this fact.