From "Seeing Double: Twins in Fiction":
The notion that one could have a split self, representing both ego and id, is a much-used element in literature -- think Jekyll and Hyde, Jonathan Harker and Dracula, Frankenstein and his Creation. Who is your Rahel? Who is your Estha?
The dark double allows for the transgression of boundaries and the reader can observe the unconscious as it enacts its instinctual will. There’s something exciting about this. Perhaps, too, our interest in twins is also sparked by a sense that our identities are not fully secure, that there is always something missing – emotionally, spiritually or physically, and that to have a twin might provide an understanding of the self, dreaded or not, that would bring completion.
Bringing together the idea of twins and literary doubles is the unanswerable question: if one had a second self, what would he or she be like?
