Joseph Conrad (1857-1924)
It is said that everyone carries within him/her own Congo. As an outer Congo was full of fear, terror, savagery and forces of temptation, so it our Congo full of dark forces. To reach the bottom line of our inner Congo it is, according to Conrad, necessary to make an outer journey to literal Congo. Our Congo is a manifestation of inner Congo. By reaching a geographic Congo by making an outer journey, it is possible to reach the center of our inner Congo.
Jung said that Marlow's journey to Congo is a descent into a subconscious. The subconscious is a vast territory, dark forces which affect our lives without making us aware of the functioning of its mechanism. Kurtz descended into the subconscious. But he failed to take control of it. He failed to handle the operation of dark forces from the level of his subconscious. Kurtz unconsciously descended into the realm of the subconscious. That is why, he can't return from it. On the contrary, Kurtz was devoured by the dark forces in the subconscious.
Marlowe's journey within is somewhat different. Unlike Kurtz Marlow descended into the subconscious with full awareness with a strict sense of self restraint and with a sense of unflinching and unwavering loyalty to a standard of norm. Kurtz was deviated from the standard of civilized ethical norms. Due to this deviation his journey within proved to be fatal. Instead of keeping firm control over the overwhelming power of subconscious forces Kurtz went on yielding to the temptations of the dark subconscious forces. That is why Kurtz became brutal and barbaric, atrocious and exploitative, rapacious and lusty. In sharp contrast to Kurtz Marlow never deviated from an established ethos. That is why he did not become a puppet in the hand of subconscious forces. He made an inner journey cautiously because he had made a cautious outer journey to Congo. Due to his durable moral rectitude, Marlow even tried to save Kurtz from his inner malaise.
There are several elements on the strength of which we can say that Heart of Darkness is a journey within. When Marlow was piloting his steamer along the river that flowed between a dense forest, Marlowe became frightened and awake in the distance. Joseph Conrad has used both awakening related symbols and dark forces-referring images. The reason behind the use of these polar opposite symbols is to produce sufficient evidences that the novel is ultimately about the inner journey.
Kurtz's utterances "Horror, Horror" suggest Kurtz's failed and futile inner journey. When Kurtz reached the depth of the inner heart of darkness, he was in no position to return and claim his civilized self. Marlow's attempt to take Kurtz back to Europe reflects Marlow's successful inner journey. Marlow succeeded in mastering his inner Congo. That is why Marlow remained untouched by the temptation of the savage self. This success of Marlow in making the inner journey successful had been exemplified by his Buddha image also. Marlow is, throughout the play, seen sitting in lotus position. His lotus position reflects his complete and triumphant inner journey.
Marlow not only reached his inner Heart of Darkness, but succeeded in coming out of it. Kurtz too managed to reach his inner Congo but failed to come out of it. Hence his inner Congo engulfed Kurtz. Two golden fact about Marlowe's journey is that he reached Congo. By reaching Congo he reached his own inner Congo. By completing his out journey he succeeded in making his own inner journey. Next equally important fact is that Marlow knew a profound and invaluable truth made him aware of the fragility of the human self. This awareness led him towards the path of self-realization. That is why Conrad's Heart of Darkness is a journey within.