How does Cecilia manage to survive her captivity, and how is her survival connected with the book's theme of imagination?

In Imagining Argentina, American author Lawrence Thornton dips into the Latin American literary tradition of magical realism (pioneered by such literary giants as Gabriel Garcia Marquez, Isabel Allende, and Jorge Luis Borges) to create cultural meaning from depictions of the fantastic—specifically, Carlos's uncanny ability to fight the government with his wondrous imagination. Carlos is in many ways the antithesis of the oppressive military government—defined by his love of theatre, art, children, and so on. And...

In Imagining Argentina, American author Lawrence Thornton dips into the Latin American literary tradition of magical realism (pioneered by such literary giants as Gabriel Garcia Marquez, Isabel Allende, and Jorge Luis Borges) to create cultural meaning from depictions of the fantastic—specifically, Carlos's uncanny ability to fight the government with his wondrous imagination. Carlos is in many ways the antithesis of the oppressive military government—defined by his love of theatre, art, children, and so on. And (possibly) because of this identity of cultural resistance, he provides his community with the gift of knowledge at a time when, historically, Argentina's people were in the dark as loved ones disappeared in the night without a trace. 

Cecilia uses her own imagination and faith from the inside of her prison as means of survival. For instance, without any means to record what was being done to her, she made use of the patterns etched into the walls as mnemonic devices (which she eventually collected in a book, The Wall). Following Teresa’s death, Carlos notes that the generals “assumed I would follow Teresa into the whiteness, give up on myself as well as Cecilia, and they were very close to being right. But as I was thinking about letting myself go I understood that Cecilia would drown too, that she lived only because I remained to know she lived" (Thornton 172). 

Roughly 30,000 people disappeared between 1976 and 1983 in Argentina's Dirty War. Imagining Argentina suggests that, when the government can take everything away from you and your family in the night, the only power left to you is your imagination, and you must wield it as fiercely as a weapon.