Thoreau thinks that there is a need to restructure society along more just lines. Thoreau's actions reveal that he sees how the society is corrupt. And that the best possible option for him is to live life in the woods reconnecting with nature.
Answer:
It's an internal conflict in the speakers mind. The speaker is distraught over the loss of Lenore and is disturbed by the raven who flies into his study and croaks nevermore reminding him of Lenore.
This here is a simple sentence my friend hope this helps :)