The speaker starts by describing a dream he used to have a “long time ago” that he has since nearly forgotten. Back then, however, it was right in front of him, bright like a “sun-dream.” A wall rose up slowly between the speaker and his dream - it rose and rose until it touched the sky. The wall is a shadow.
The speaker proclaims, “I am black.” He lies down in the shadows, which prevent the light of the dream from shining on him. All he can see is the “thick” wall and the shadow.
He cries, “My hands! / My dark hands!” He wants to break through the wall and find his dream; he wants to break apart the darkness and “smash” the night. He wants that shadow to break apart into a “thousand lights of sun” and “a thousand whirling dreams / of sun!”
“As I Grew Older” contains a narrative about struggle and empowerment that shares thematic similarities with “Dreams” and “Harlem.”
In the beginning of the poem, the speaker recalls a dream he had long ago and had nearly forgotten, but now he can see it ahead of him once more. This is fairly straightforward symbolism - the speaker represents all African Americans who had to relinquish their dreams due to the pervasive discrimination and persecution in early 20th century American society. African American children may have experienced a few brief years of blissful ignorance (like the speaker), but they all eventually became aware of their status as second-class citizens - a wall of injustice that rises up to gradually block the sunlight. Just because the wall has risen up, though, it does not mean that the dream ceases to exist - the speaker simply cannot not see it anymore.
Hughes deliberately uses the symbol of a shadow as a way to actualize his character's blackness, because the speaker's race is the barrier that is keeping him from achieving his dream. When the narrator describes lying hidden in the shadows, Hughes invokes Ralph Ellison's depiction of his African American narrator in Invisible Man (1952): “I am an invisible man. No, I am not a spook like those who haunted Edgar Allan Poe; nor am I one of your Hollywood-movie ectoplasms. I am a man of substance, of flesh and bone, fiber and liquids -- and I might even be said to possess a mind. I am invisible, understand, simply because people refuse to see me.”
As the poem progresses, though, the speaker's listlessness and apathy turns into determination and vigor, creating a shift of energy. The speaker forcefully commands his “dark hands” to break through the wall so he can access his dream. He is no longer willing to let it languish beyond his grasp. He wants to “shatter this darkness" and “smash this night.” Hughes uses this violent language to show that the speaker is suddenly empowered and feels no equivocation or anxiety about what he must do.
The concluding image is fantastic, as the speaker imagines the shadow breaking apart into thousands of fragments of sunlight and liberating the “whirling dreams / Of sun!” By confronting the obstacle, the speaker has found his voice and his purpose. This is a potential allusion to the Greek myth of Icarus. Icarus was tantalized by the brilliance and glory of the sun and built himself wax wings to fly there. However, his excitement caused him to fly much too close, his wings melted, and he plummeted into the sea. Although there is a risk inherent in the speaker's decision to shatter the “thick wall," the largely affirmative tone of the second half of the poem seems to suggest that even if he fails, there is spiritual value in possessing the self-realization to grasp for a dream that might be out of reach.