Memory
Memory emerges as a central theme throughout the novel. The veracity of Grace's claim that she has no memory of the murders is of pivotal importance to the arguments for and against her innocence. The recovery of memory, then, is of fundamental importance for the novel's resolution. However, Grace's loss of consciousness and memory following the deaths of her mother and Mary Whitney, together with the conflicting testimonies regarding events and the individuals involved, repeatedly reveal the fragile, unstable nature of memory, particularly where traumatic events are concerned.
As Simon seeks to reawaken Grace's memories, he becomes increasingly uncertain of his own agenda and priorities. At the end of the novel, Simon loses his own memory due to a head injury. He no longer recalls his own ambition to work with the mentally ill.
Identity
The title of the novel, "Alias Grace", already points to the central importance of Identity in the narrative. An "alias" is an assumed secondary identity. Grace has a number of "aliases" projected onto her in the course of the novel - from innocent victim to foolish dupe to dangerous seductress to murderess. She also, consciously or unconsciously, assumes different identities herself, modifying her behaviour and her story in the hope of pleasing Dr. Jordan and then forsaking her own self altogether to take on the persona of Mary Whitney when under hypnosis.
An interesting parallel development of the theme can be found in the character of Jeremiah the pedlar, who undergoes a series of chameleon -like transformations over the course of the text. His identity is rendered all the more uncertain by the unreliability of Grace as a narrator, which leaves a big question mark as to whether all the different characters are really the same man. As a male character on the margins of society, Jeremiah displays a greater freedom than Grace or Simon. Both Grace and Simon end up in some sense imprisoned, the former literally, in part because she was a working class woman, the latter metaphorically, because of the constraints of society.
Class and Gender
Alias Grace centers on the deaths of three working-class women (Grace's mother, Mary Whitney, and Nancy Montgomery) and the ultimate reprieve of a fourth (Grace Marks). Throughout the novel, we are invited to consider how the fates of these women compare to those of women of a higher social class and to those of men who are guilty of similar social transgressions. Mary Whitney and Nancy Montgomery both pay with their lives after having sexual relations out of wedlock with men from a superior social class. The middle-class Rachel Humphries is disgraced socially as a consequence of her relationship with Simon Jordan, but at least escapes with her life. Neither Simon nor Thomas Kinnear faces particularly heavy social consequences for their behavior. Significantly, Grace Marks and James McDermott are tried and condemned for the murder of Kinnear alone, implying on some level that Nancy's murder was less significant.
Truth, guilt and innocence
Alias Grace highlights the slippery nature of truth, guilt and innocence in a world riddled with uncertainty, limited perspectives and the unstable nature of the the human mind. As a convicted criminal with (alleged) amnesia, Grace Marks, the novel's unreliable, homodiegetic narrator, openly admits that her story cannot be trusted. Even in her first visit with Dr. Jordan, Grace openly acknowledges the performance of storytelling and truth, playing the role she thinks he wants her to play: 'I look at him stupidly. I have a good stupid look which I have practiced.'
Grace also conceals thing from the reader, meaning that, like Dr Jordan, the audience must decide for themselves which parts of her story are true, which are lies, and which may be a bit of both. The multiple, conflicting accounts of the Kinnear–Montgomery murders highlight this, emphasising the way Grace moulds the 'truth' into many different accounts. Later in the book, Grace also claims that guilt is not determined by somebody's actions, but as a result of "the things that others have done to you." Atwood leaves it ambiguous as to whether Grace is justifying her actions, and is thus guilty, or simply stressing the importance of emotional truths over concrete ones.
Further complicating the novel's relation to truth, the text is also littered with authentic historical documents, including newspaper clippings, excerpts from the Kingston Penitentiary Behavior Guidelines and, of course, the actual confessions from Grace and McDermott. Atwood's intermingling of different accounts helps muddy the idea of truth, enabling 'true character of the historical Alias Grace to remain an enigma.'
