“When love is not madness it is not love.”

Pedro Calderon de la Barca
Pedro Calderón de la Barca y Barreda González de Henao Ruiz de Blasco y Riaño, usually referred as Pedro Calderón de la Barca, was a dramatist, poet and writer of the Spanish Golden Age. During certain periods of his life he was also a soldier and a Roman Catholic priest.
Source: Wikipedia