Máximo Manso, a teacher at a prep school, is a shy, middle-aged bachelor who is average in everything but intellect. The devotion to reason that governs his life leads him to believe that it should guide his choice of wife as well. Choosing Irene because he mistakenly believes that she is serious and values reason, he soon falls deeply in love despite her true personality. This inconsistent behavior deeply threatens his his worldview. After losing the girl, he dies disoriented and heartbroken.

Irene, a beautiful orphan who is 19 years old, is the object of many men’s desire. Because she is poor, she is unlikely to marry a wealthy man but determined to do so. Beneath her public, calculatedly reasonable appearance, which attracts Máximo, is a conniving, superficial social climber. She is better suited to and marries the politically ambitious Manuel Peña.

Manuel Peña, age 21, is one Manso’s former students. Wealthy, good-looking, charming, and sociable, he is Máximo’s opposite. Peña is wealthy but not born into the elite: his mother, Javiera Rico de Peña, owns a butcher shop. He loves and marries Irene, dashing Manso’s hopes. Ascending swiftly in politics, Manuel enters Parliament.

José María Manso is Máximo’s older brother who earned great wealth in Cuba. He is a practical and politically-oriented man who enjoys socializing and intrigue. His efforts to seduce Irene are rebuffed.

Candida de García Grande is Irene’s elderly aunt. The once wealthy Señora de García Grande has declined into penury since becoming a widow. Superficial and deceitful, as she depends on the generosity of others for support, she uses Irene to lure wealthy men who can provide this. She tries to enable José María’s pursuit of her niece.

Lica is José María’s lovely, sensitive wife whose naïveté blinds her to her husband’s true nature and is ill-suited to his political ambitions. She depends on Máximo as a confidant.