This thesis examines the dichotomy of locura/cordura in Miguel de Cervantes' Don Quijote de la Mancha (1605/1615), specifically the nature of the madness of the titular character. Two different aspects of the Quijote are discussed: (1) the dual nature of the personality of Don Quijote/Alonso Quijano as being "sanely insane," that is, that although Don Quijote exhibits symptoms unmistakably indicative of madness, he maintains his sanity underneath this mad façade; the dedicatory sonnets that precede Part 1, the epitaphs that follow the end of Part 1, and the two poems that serve as an epilogue to Part 2 are examined in length in order to show that Don Quijote, and not "Alonso Quijano el Bueno," is the true protagonist of the Quijote; and (2) the roles that the various encantadores play in the Quijote and how they interact with Don Quijote are discussed in order to further explore this dichotomy of locura/cordura.