Literary genres which critics have applied as a framework for interpreting the novel include religious allegory, fable, detective story, sensation fiction, Doppelgänger literature, Scottish devil tales, and gothic novel.
The novella is frequently interpreted as an examination of the duality of human nature, usually expressed as an inner struggle between good and evil, with variations such as human versus animal, civilization versus barbarism sometimes substituted, the main thrust being that of an essential inner struggle between the one and other, and that the failure to accept this tension results in evil, or barbarity, or animal violence, being projected onto others. In Freudian theory, the thoughts and desires banished to the unconscious mind motivate the behaviour of the conscious mind. If someone banishes all evil to the unconscious mind in an attempt to be wholly and completely good, it can result in the development of a Mr Hyde-type aspect to that person's character. This failure to accept the tension of duality is related to Christian theology, where Satan's fall from Heaven is due to his refusal to accept that he is a created being (that he has a dual nature) and is not God. This idea is suggested when Hyde says to Lanyon, shortly before drinking the famous potion – "...and your sight shall be blasted by a prodigy to stagger the unbelief of Satan." This is because in Christianity, pride (to consider oneself as without sin or without evil) is the greatest sin, as it is the precursor to evil itself.
In his discussion of the novel, Vladimir Nabokov argues that the "good versus evil" view of the novel is misleading, as Jekyll himself is not, by Victorian standards, a morally good person in some cases.
Public vs private
The work is commonly associated today with the Victorian concern over the public and private division, the individual's sense of playing a part and the class division of London. In this respect, the novella has also been noted as "one of the best guidebooks of the Victorian era" because of its piercing description of the fundamental dichotomy of the 19th century "outward respectability and inward lust," as this period had a tendency for social hypocrisy.
Scottish nationalism vs union with Britain
Another common interpretation sees the novella's duality as representative of Scotland and the Scottish character. In this reading, the duality represents the national and linguistic dualities inherent in Scotland's relationship with the wider Britain and the English language, respectively, and also the repressive effects of the Church of Scotland on the Scottish character. A further parallel is also drawn with the city of Edinburgh itself, Stevenson's birthplace, which consists of two distinct parts: the old medieval section historically inhabited by the city's poor, where the dark crowded slums were rife with all types of crime, and the modern Georgian area of wide spacious streets representing respectability.