In the following essay, Axel Nissen discusses the effects of "perspectival principle" in Welty's story.

In her introduction to the first edition of A Curtain of Green and Other Stories (1941), Katherine Anne Porter describes the heroine of "Why I Live at the P.O." as "a terrifying case of dementia praecox," effectively labeling her as a mental basket case. Though Ruth Vande Kieft has described Porter's comment as "the Ur-blooper" of Welty criticism ("Question"), the idea has stuck and poor Sister has been on the psychiatrist's couch ever since. In his monograph published in 1965, Alfred Appel, Jr. more or less accepts Porter's diagnosis and writes: "As the narrator continues her straightforward account, the reader becomes aware of penetrating inconsistencies." Marie-Antoinette Manz-Kunz also follows Porter's lead when she states that the "story is a sheer clinical study of the distortions of reality caused by mental disorder." Charles E...