Friendship
In this poem, the commitments of friendship are inexorably tied to the innate talents of the artist. In honoring his friendship with Oldham, the speaker describes himself as hoping not only to memorialize a personal relationship, but as wishing to carry on a writerly legacy. In fact, by comparing his friend to Nisus, who sacrifices his own success (and sabotages others') for a friend, Dryden links loyalty in friendship to collaboration in athletic or artistic achievement. Meanwhile, the foundation of his friendship is partially based on writing. The speaker admires Oldham as a poet as well as a friend, and considers him a source of artistic inspiration. These artistic ties aren't portrayed as impersonal or purely intellectual. Instead, they are, according to Dryden, signs that the two writers' very souls have a kinship.
Mortality
A particularly difficult aspect of Oldham's death, as Dryden portrays it, is the amount of unresolvable uncertainty that it creates. Because Oldham died young, it's not clear what kind of poet he would have become. Would his work have mellowed to the point of losing its potency, or improved with the practice and wisdom of age? For the speaker, these questions are especially frustrating because of the irreversible and arbitrary nature of death. Oldham's life has ended early, completely by chance, leaving him without the time that Dryden himself has—which would have allowed him either to grow or to decline as a writer.
Poetry
Dryden's analysis of Oldham's work offers an interesting point of view on what constitutes good poetry and in particular good satirical poetry. By explaining that their "souls were near ally'd,...cast in the same poetic mould," Dryden first suggests that writing style is tied to innate personality, meaning that the two satirists share deeper similarities. He later mentions that Oldham's work, despite its wittiness, is somewhat technically imperfect. Yet technical perfection in satire, while a good thing, is far from the most important factor in a poem's quality. Instead, Dryden speaks most highly of sharpness and cleverness in poetry.
