La Recherche de l'absolu is one of the great novels of the Philosophical Studies, devoted to the devouring passion for knowledge. At Douai, in Flanders, lives Balthazar Claës, a rich gentleman of noble lineage, fulfilled husband of the tender Joséphine, called Pépita, and respected father of a family. But Balthazar is seized by a scientific obsession: convinced of the existence of a single principle at the origin of all matter, he devotes himself body and soul to the quest for "the absolute," that primal substance whose discovery would revolutionize chemistry and yield him the secret of creation. This monomania turns into delirium and engulfs everything: Balthazar devotes growing sums to his experiments, neglects his family, dissipates the family fortune in his laboratory, sacrificing the happiness and security of his wife and children to his chimera. Joséphine, who loves him to distraction, witnesses powerless the material and moral ruin of their home and finally dies of grief. Their eldest daughter, Marguerite, devoted and courageous, then struggles to save what can be saved of the patrimony and to preserve the family's future against the paternal blindness. Ruined, fallen, but still possessed by his faith in the absolute, Balthazar Claës at last dies, believing in his final breath that he grasps the long-sought truth, crying out a visionary's "Eureka!" Balzac paints the passion of science as a force as destructive as avarice or love, capable of annihilating an entire life and family. The novel illustrates the great law of the Philosophical Studies: thought, the fixed idea, consumes the one it inhabits. Through the tragic destiny of the chemist, La Recherche de l'absolu meditates on genius, excess, and the exorbitant price of the quest for ultimate knowledge.