"Of the wide world I stand alone, and thinkTill love and fame to nothingness do sink." (13-14)
Keats' final couplet concludes his anxious poem "When I Have Fears." Many poets use the common practice of 'turning' the direction or meaning of the sonnet by introducing a new or contrasting view in toward the end of the poem; the fancy word for this is 'peripeteia' and it most commonly occurs in the third stanza.
Keats begins his reversal at the end of line twelve. The last two lines of "When I Have Fears" suggests that the speaker has realized that his desire for fame and love are not so important when measured against the scope of the "wide world" (13). In the beginning of the poem, the speaker worries about dying before he could write or create all of his masterpieces; however, after contemplating the beauty of the night sky, the speaker's worries "sink" into "nothingness," meaning that he realizes these concerns are insignificant.