One might question the extent to which Dr. Jekyll and Mr. Hyde are in fact a single character. Until the end of the novel, the two personas seem nothing alike—the well-liked, respectable doctor and the hideous, depraved Hyde are almost opposite in type and personality. Stevenson uses this marked contrast to make his point: every human being contains opposite forces within him or her, an alter ego that hides behind one's polite facade. Correspondingly, to understand fully the significance of either Jekyll or Hyde, we must ultimately consider the two as constituting one single character. Indeed, taken alone, neither is a very interesting personality; it is the nature of their interrelationship that gives the novel its power.
Despite the seeming diametric opposition between Dr. Jekyll and Mr. Hyde, their relationship in fact involves a complicated dynamic. While it is true that Jekyll largely appears as moral and decent, engaging in charity work and enjoying a reputation as a courteous and genial man, he in fact never fully embodies virtue in the way that Hyde embodies evil. Although Jekyll undertakes his experiments with the intent of purifying his good side from his bad and vice versa, he ends up separating the bad alone, while leaving his former self, his Jekyll-self, as mixed as before. Jekyll succeeds in liberating his darker side, freeing it from the bonds of conscience, yet as Jekyll he never liberates himself from this darkness.
Jekyll's partial success in his endeavors warrants much analysis. Jekyll himself ascribes his lopsided results to his state of mind when first taking the potion. He says that he was motivated by dark urges such as ambition and pride when he first drank the liquid and that these allowed for the emergence of Hyde. He seems to imply that, had he entered the experiment with pure motives, an angelic being would have emerged. However, one must consider the subsequent events in the novel before acquitting Jekyll of any blame. For, once released, Hyde gradually comes to dominate both personas, until Jekyll takes Hyde’s shape more often than his own. Indeed, by the very end of the novel, Jekyll himself no longer exists and only Hyde remains. Hyde seems to possess a force more powerful than Jekyll originally believed. The fact that Hyde, rather than some beatific creature, emerged from Jekyll’s experiments seems more than a chance event, subject to an arbitrary state of mind. Rather, Jekyll’s drinking of the potion seems almost to have afforded Hyde the opportunity to assert himself. It is as if Hyde, but no comparable virtuous essence, was lying in wait.
This dominance of Hyde—first as a latent force within Jekyll, then as a tyrannical external force subverting Jekyll—holds various implications for our understanding of human nature. We begin to wonder whether any aspect of human nature in fact stands as a counter to an individual’s Hyde-like side. We may recall that Hyde is described as resembling a “troglodyte,” or a primitive creature; perhaps Hyde is actually the original, authentic nature of man, which has been repressed but not destroyed by the accumulated weight of civilization, conscience, and societal norms. Perhaps man doesn’t have two natures but rather a single, primitive, amoral one that remains just barely constrained by the bonds of civilization. Moreover, the novel suggests that once those bonds are broken, it becomes impossible to reestablish them; the genie cannot be put back into the bottle, and eventually Hyde will permanently replace Jekyll—as he finally does. Even in Victorian England—which considered itself the height of Western civilization—Stevenson suggests that the dark, instinctual side of man remains strong enough to devour anyone who, like Jekyll, proves foolish enough to unleash it.
Although Utterson witnesses a string of shocking events, Utterson himself is a largely unexciting character and is clearly not a man of strong passions or sensibilities. Indeed, Stevenson intends for him to come across in this way: from the first page of the novel, the text notes that Utterson has a face that is “never lighted by a smile,” that he speaks very little, and that he seems “lean, long, dusty, [and] dreary.” Yet, somehow, he is also “lovable,” and dull and proper though he may be, he has many friends. His lovability may stem from the only interesting quality that Stevenson gives him—namely, his willingness to remain friends with someone whose reputation has suffered. This loyalty leads him to plumb the mystery that surrounds Jekyll.
Utterson represents the perfect Victorian gentleman. He consistently seeks to preserve order and decorum, does not gossip, and guards his friends’ reputations as though they were his own. Even when he suspects his friend Jekyll of criminal activities such as blackmail or the sheltering of a murderer, he prefers to sweep what he has learned—or what he thinks he has learned—under the rug rather than bring ruin upon his good friend.
Utterson’s status as the epitome of Victorian norms also stems from his devotion to reason and common sense. He investigates what becomes a supernatural sequence of events but never allows himself to even entertain the notion that something uncanny may be going on. He considers that misdeeds may be occurring but not that the mystical or metaphysical might be afoot. Thus, even at the end, when he is summoned by Poole to Jekyll’s home and all the servants are gathered frightened in the hallway, Utterson continues to look for an explanation that preserves reason. He desperately searches for excuses not to take any drastic steps to interfere with Jekyll’s life. In Utterson’s devotion to both decorum and reason, Stevenson depicts Victorian society’s general attempt to maintain the authority of civilization over and against humanity’s darker side. Stevenson suggests that just as Utterson prefers the suppression or avoidance of revelations to the scandal or chaos that the truth might unleash, so too does Victorian society prefer to repress and deny the existence of an uncivilized or savage element of humanity, no matter how intrinsic that element may be.
Yet, even as Utterson adheres rigidly to order and rationality, he does not fail to notice the uncanny quality of the events he investigates. Indeed, because we see the novel through Utterson’s eyes, Stevenson cannot allow Utterson to be too unimaginative—otherwise the novel’s eerie mood would suffer. Correspondingly, Stevenson attributes nightmares to Utterson and grants him ominous premonitions as he moves through the city at night—neither of which seem to suit the lawyer’s normally reasonable personality, which is rarely given to flights of fancy. Perhaps, the novel suggests, the chilling presence of Hyde in London is strong enough to penetrate even the rigidly rational shell that surrounds Utterson, planting a seed of supernatural dread.
Lanyon plays only a minor role in the novel’s plot, but his thematic significance extends beyond his brief appearances. When we first encounter him, he speaks dismissively of Jekyll’s experiments, referring to them as “unscientific balderdash.” His scientific skepticism renders him, to an even greater extent than Utterson, an embodiment of rationalism and a proponent of materialist explanations. As such, he functions as a kind of foil for Jekyll. Both men are doctors, well respected and successful, but they have chosen divergent paths. From Lanyon’s early remarks, we learn that Jekyll shared some of his research with Lanyon, and one may even imagine that they were partners at one point. But Lanyon chooses to engage in rational, materialist science, while Jekyll prefers to pursue what might be called mystical or metaphysical science.
It is appropriate, then, that Lanyon is the first person to see Jekyll enact his transformations—the great advocate of material causes is witness to undeniable proof of a metaphysical, physically impossible phenomenon. Having spent his life as a rationalist and a skeptic, Lanyon cannot deal with the world that Jekyll’s experiments have revealed. Deep within himself, Lanyon prefers to die rather than go on living in a universe that, from his point of view, has been turned upside down. After his cataclysmic experience, Lanyon, who has spent his life pursuing knowledge, explicitly rejects the latest knowledge he has gained. “I sometimes think if we knew all,” he tells Utterson, “we should be more glad to get away.” With these words, Lanyon departs from the novel, his uncompromising rationalism ceding to the inexplicable reality of Jekyll.