In Heart of Darkness by Joseph Conrad, Kurtz is worshiped as a god among men. Armies of natives move at his behest, and Company merchants wonder at his effectiveness. Even in his decrepit physical state, his body “pitiful and appalling” (p.74), his eloquence holds such influence that native chiefs grovel through his skull-encircled garden. Above all, he is supposedly a moral man, a member of “the gang of virtue” (p.30). Even Marlow believes this. For much of the story Kurtz provides him a beacon of hope in the surrounding darkness. However, the facades crumble as Kurtz attempts to escape. Unable to walk, he drags himself through the long grass, seeking the refuge of the natives’ bonfires beyond the curtain of the woods. He drags himself onwards, knowing that the crew of the steamer has come to tear him from his kingdom. Marlow intercepts his wretched peregrination, and bears witness to the essence of Kurtz: the ruling passions and instincts which define his character. Kurtz is not transcendent, he is not a virtuous “Worker” (p.14) of God. Instead, as Kurtz crawls from his hut, the last remnants of his soul descend into the unrestrained darkness of the wilderness.

As Marlow confronts him, Kurtz stands to voice his final protest. He musters his remaining strength and commands, “‘Go away—hide yourself.’”(p.81) His voice is “profound” and full of “vigour.” The voice that moved the heart of the countless natives, of the Russian, of the pilgrims, remains. However, what Marlow hears is viscerally “awful,” as it emanates from something not fully human: “He rose unsteady, long, pale, indistinct, like a vapour exhaled by the earth” (p.81). He does not rise as a man, but rather an “indistinct … vapour.” He rises as a miasmic wraith. Though his voice is vigorous, his flesh is “pale.” Though his voice is profound, his body is “indistinct.” In rising, by displacing his head only a few feet from the dirt of the wilderness, his concrete humanity diminishes. To Marlow he is a “Shadow,” a shadow so much a figment of the earth that he appears to be “exhaled” by it. Behind Marlow, before this Shadow, a fire dances, silhouetting a “black figure” with “antelope horns.” It appears “fiend-like enough”(p.81) to Marlow. The image is unmistakable — Kurtz is crawling inexorably towards the depths of hell.

Marlow’s characterization of the wilderness, of its dark, hellish depths, makes its allure clear. Kurtz is captive to “the heavy, mute spell of the wilderness—that seemed to draw him to its pitiless breast by the awakening of forgotten and brutal instincts, by the memory of gratified and monstrous passions” (p.82). Kurtz is bound to this moral nadir. Surrounded by this amorphous wilderness, he has become addicted to the “brutal instincts” and “monstrous passions” long forgotten by the progression of western civilization. These lusts now rule him. They “draw” him in and cradle him in their “pitiless breast[s].” Even in his mortal sickness he crawls towards the “fiend-like” men and fires. 

As Marlow had concluded earlier, Kurtz’s principles pale in comparison to his unchained desires. The brutal primitivism of the jungle, the freedom to exist “beyond the bounds of permitted aspirations” (p.82), rules Kurtz’s inner being. His soul, the uniquely human amalgamation of restraint and morality, is subsumed by the draw of the “monstrous” wilderness. Tangible moral direction and humanity are replaced by a “Shadow—this wandering and tormented thing” (p.82).  To Marlow, his soul is “‘irretrievably lost’” (p.82).  Marlow is staggered by this notion. In stunned, horrified disbelief, he probes the strength of Kurtz’ connection to the wilderness: “‘Do you know what you are doing,’” he asks. Kurtz musters his remaining strength— the vigor of his voice—to respond: “‘Perfectly,’ he answered” (p.81). Thus, Kurtz willingly gives up whatever remains of his soul, his renowned “virtue,” his love for his intended, his promised legacy, to remain in the heart of darkness, to remain in the embrace of its “heavy, mute spell.” Thus, Kurtz willingly steps irreversibly into a moral abyss. Marlow physically experiences the pull of the wilderness on Kurtz as he carries him back to the hut: “When I had him at last stretched on the couch … my legs shook under me as though I had carried half a ton on my back.” (p.83). Kurtz was a “vapour” as he rose, but in descent he is solidly “half a ton.” Kurtz is so firmly pulled to the earth that Marlow staggers under the weight of his wraith-like body, though he should be “not much heavier than a child” (p.83). This Shadow pulls almost single-mindedly downwards, with “no restraint, no faith, and no fear” (p.83), with the amoral heaviness of the dark jungle. The shred of humanity within Kurtz, the shred of “clear intelligence” is “concentrated, it is true, upon himself with horrible intensity,” in a desperate attempt to free itself from the invading darkness. However, the “pitiless breast” of the wilderness is loath to release its prince. Torn between the two, Kurtz’s soul is further destroyed — “by heavens! I tell you, it had gone mad” (p.83). As Marlow carries him down the hill, the invading darkness prevails, dragging Kurtz to the ground with the inevitability of gravity.

“No eloquence could have been so withering to one’s belief in mankind as his final burst of sincerity” (p.83). Kurtz’s actions and decision reveal a crack in the very fabric of mankind. He has descended so far beneath the threshold of human morality that “I [Marlow] before him did not know whether I stood on the ground or floated in the air” (p.82). Kurtz has redefined the lowest ground, the depth of depravity to which a being can descend. Kurtz has revealed that the true depths lie far beneath Marlow’s ground, in the “impenetrable darkness” (p.86) of unrestrained instinct and passion. Marlow now stands at the edge of a “precipice where the sun never shines” (p.86), while Kurtz is “lying at the bottom” (p.86) of the amoral abyss. The risk of falling, of all “mankind” falling, to the same depths Kurtz pursued with his “final burst of sincerity,” withers one of Marlow’s most innate beliefs — faith in humanity, faith that humans are more than “brutal” and “monstrous” beasts. Kurtz’s descent is so stark that Marlow feels as though the ground, the bedrock of society, has suddenly shattered, leaving him, and with him the entirety of the modern world, to “float[ed] in the air.” 

Kurtz, as he crawled before Marlow, is fused spiritually and physically to the ground. The descent of his soul reveals a new nadir of human existence. Marlow condemns Kurtz as mad, as “utterly” destroyed by internal conflict, but the reader cannot help but suspect that within each human, the same tether exists, pulling inexorably downwards.