Though Hughes' dream is not explicitly stated in the poem, it is implied. Certain lines tell us that he has fought for his dream and others suggest he succeeded in fulfilling his dream. From these we can infer and deduce his dream.

My hands!
My dark hands!
Break through the wall!
Find my dream!

Here it is implied that Hughes fought for his dream. Since the verbs "break" and "find" are in base form, they might be understood as commanding an upcoming action or as reporting a present action as in the paraphrase "My hands break through now." The verbs might also be understood as part of ellipsised "do" auxiliary phrases: "do break" "do find." This construction renders a timelessness to the meaning since "My hands do break" might be an action performed in the present moment, with results yet unrevealed, or "My hands do break" might be a flashback to memory of a previous time, which would mean results are known and fulfilled.

Hughes' syntax encompasses three possible and--more importantly--three combined time references: commanding upcoming action, reporting present action, recalling past action. An important aspect of this multiplicity is that the third implies known and fulfilled results.

The lines that suggested successful result and support the "do break" understanding of the verbs "break" and "find" are:

Help me to shatter this darkness,
...
Into a thousand whirling dreams
Of sun!

Adding further complexity to the multiplicity of time references, these lines move the verbs "break" "find" and "help" into a future continuous present moment with ongoing results. In other words, with finished poem after finished poem, Hughes continually cries out "My hands do break, do help; thus I do shatter; thus I do break this night and shadow."

Here, we are moved to ask the questions, if Hughes breaks through and finds his dream, and if his finding is continuously breaking shadow into sun, then (1) what is it he is doing; (2) what was his dream? The answers are that (1) he is writing world renowned poetry and that (2) his dream in youth--which he finds again by breaking walls--was to be a poet. And a poet he is, a poet who found his way:

Help me to shatter this darkness,
To smash this night,
To break this shadow
Into a thousand lights of sun,
Into a thousand whirling dreams
Of sun!  

Of course the "wall" that divided him from his dream and threw up the shadow that covered him in dreamless darkness was segregation and racism. Segregation restricted his educational opportunities and the belief people had in his talent and it engendered the false, spurious beliefs people held about him as a man.

The dream is not specified, but it can be taken as referring to Hughes' hopes and aspirations in general. When he was young and knew little about the world, this dream shone bright, but as he grew older he came to realise that his path was blocked simply because of his colour; being black, he was denied his opportunities and his rights. For a time he was held back by this, but he did not give up. He sees himself as smashing through the barriers placed before him. The poem can therefore be taken as a comment on the historically marginalized status of African Americans but also shows how they were capable of rising above social oppression, as illustrated by the success of the civil rights movement.