Insanity plays into the American gothic tradition that “things are not what they seem”. When the concept of insanity is introduced into the text there is no longer a distinct difference between “right” and “wrong”. At the beginning of the text the reader believes that Sybil has been wrongly accused of having a mental illness. As the story goes on Sybil beings sleep walking and hearing voices. At one point Sybil believes that she may be insane and begs for Mercy from her uncle. “I stretched my hands to them, crying with an imploring cry, ‘Yes I am quite! I am hopeless!’” (236). Due to the fact that insanity is so complex there is no longer a distinct difference between what is “right” and “wrong”, and “good” and “bad”. We, as the reader, no longer know what to believe is the truth and what could be caused by mental illness.
Our prior ideas about mother/daughter relationships were based on the fact that the daughter should aspire to be like her mother. In the relationship between Sybil and her mother, Sybil learns about life and what to avoid from her mother’s mistakes. Though unknowing that she is warning her daughter Sybil’s mother instructs her to escape before Sybil ends up with the same mental problems as her. “What devil sent you I may never know, but I long to warn you” (238). Sybil was also not to be granted her father’s land if she was misfortunate enough to have the same illness as her mother. “If it should appear that I inherited my mother’s malady, the fortune should revert to my cousin” (240). Through the hardships of her mother Sybil is able to learn how to better live her own life. This type of mother/daughter relationship is very different from relationships that we have previously seen.