The main conflict in the poem The Raven, by Edgar Allan Poe, is the reality of the narrator versus what is going on in his mind. The poem is about the inability of letting go of the past. It is also about how we, as humans, tend to associate symbols, sounds, and ideas with the emotions that we feel at one particular moment.
Yet, in The Raven, the more the narrator tries to get rid of the memories of his lost love, the more he holds on to them, making it impossible for him to move on.
The narrator is a man who is isolated during the cold and dark month of December in, what seems to be, a cottage. He is obviously in mourning and going through a period of deep grief.
In the middle of his sadness he sees a black raven, who enters his place, and reminds him more of the sad memory of the loss of the love of his life. He compares the raven to many different things, but he certainly personifies it as a harborer of bad news. The bird is seemingly quite comfortable inside the cottage, and does not leave. This is interpreted by the narrator as an allegory to the memories that will not leave him either.
Therefore, this conflict between forgetting versus remembering and letting go versus keeping alive the memory, is what composes the main problem in the poem.
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The raven acts as the grotesque of the lake in the darkness to fool the speaker. The raven's objective is to mess with the speaker's mind so that he will go insane and commit suicide so that the raven can eat him.