Most efforts to classify psychopathology, including the earliest, have focused on phenomenology, on syndromes of psycbputbbgy , the "grouping of signs and symptoms, based on their frequent co-occurrence, that may suggest a common underlying pathogenesis, course, familial pattern, or treatment selection" (American Psychiatric Association [APA], 1994). Hippocrates recognized and labeled the familiar syndromes of mania, melancholia, and paranoia 2,500 years ago; he blamed them on imbalance in the four essential humors: black bile, yellow bile, blood, and phlegm.Hippocrates's threefold syndromal division, endorsed by Plato a century later, held sway in one form or another throughout the Western world until Phillippe Pinel, at about the time of both the French and American revolutions, offered a modestly more complex classification system. Pinel's influential system identified five syndromes: melancholia, mania, mania with delirium, dementia, and idiotism. The development of this nomenclature coincided with the rise of asylums for the insane, for which Pinel was partly responsible; both Pinel's system and the availability of large numbers of patients in asylums paved the way for the marked