It has been said that although Conrad may not have been "the greatest novelist, he was certainly the greatest artist every to write a novel". I feel that this is an apt description of Conrad's writing style in Heart of Darkness (1902), as he paints many verbal pictures by using expressive words and many figurative descriptions of places and people. An extensive use of words relating to colour, is evident throughout the novella. The idea of darkness (and light) is emphasized from the title of the novella, and continues to play an important role throughout in the story .
My opinion is that Conrad felt that using "darkness" as a recurring theme throughout the story would be an effective tool because of the many connotations of darkness. Darkness can, for example, represents evil, the unknown, mystery, sadness or fear. Also important is the way darkness and light can be used to represent two opposite emotions or concepts.
Light vs. dark can, for example, represent good vs. evil, the civilized vs. the uncivilized, illusion vs. reality or assumption vs. fact.
We know from the start of the novella that the darkness that Conrad refers to is symbolic, because, while the silent narrator aboard The Nellie comments on the many lights emanating from the shore, the lighthouse, the other boats and the setting sun, Marlowe comments that they themselves are in "one of the dark places of the earth". Therefore we know that Marlowe has his own opinion and explanation of what the darkness is, and if we assume that this story is autobiographical, and Marlowe is a mouthpiece for Conrad, then this explanation actually indicates Conrad's personal views on what the darkness is.
Nigerian novelist, Chinua Achebe attacked Heart of Darkness as racist. He felt that Conrad used the darkness to...