What are the similarities between Edgar Allen Poe's poem "The Raven" and Robert Frost's poem "The Road Not Taken"?
Both poems can be seen to be about moving on. In "The Road Not Taken" a person comes to a fork in the road and has to choose a side. In "The Raven" the speaker is trying to move on metaphorically, from losing his love.
Both poems can be compared through an analysis of the way in which both speakers are haunted by what could have happened and what could have been had things turned out differently. However, though both speakers are shown to dwell on the past, there is a definite difference between the two, with the speaker of "The Raven" choosing to wallow in remembrance in a very unhealthy way, to the extent that he interprets everything through his distorted perception and ends up torturing himself. There is a big difference between him and the speaker of the other poem, who remembers the other road that he did not take "with a sigh."
In both poems there is a tone of rue, for what has been lost can never be reclaimed. For the speaker in Frost's poem, it is the opportunities of the road "not taken," while in Poe's poem, the speaker bemoans the loss of his Lenore.
I think in both cases, the speaker is putting all of the meaning into the thing he is looking at.
In Frost's poem, there's no difference between the paths, but the speaker makes a difference in his mind. He is completely making up the significance of the paths.
In "The Raven," the speaker is also completely making up the significance of the raven. All it ever does is say "nevermore" while the speaker provides the meaning. The speaker asks all these questions where "nevermore" is a horrible answer. What if the speaker had asked "am I going to be sad?" Then the raven would say "nevermore" and everything would be great.
So in both poems you have these meaningless things (the paths, the bird) and the speaker completely makes up their supposed meanings.
This is an interesting question with a wide range of possible answers. I want to point you in just one of many possible directions.
Consider the speaker and the situation in both poems. In both poems, there is a single, solitary speaker who reflects on the significance of something that the speaker observes. (It might seem that the "The Raven" has two speakers -- the human and the bird -- but I see the bird as a device, not a speaking creature.)
I'll stop here, but I think there's definitely more to say on this point, just as there are no doubt other similarities to explore.