Pope's "Epistle to Dr. Arbuthnot" (1735), addressed to his good friend Dr. John Arbuthnot, is both a vitriolic attack on Pope's literary and political enemies--most notably, Joseph Addison and Lord Hervey--and a self-portrait of Pope, the man and poet. As your question implies, Pope uses the poem as a way to dramatize his virtues by contrast with writers like Addison and Lord Hervey ("Sporus") who are satirized in, at times, vitriolic terms. Scholars routinely debate whether the epistle demonstrates Pope's virtues or his vices as a satirist, some arguing that Pope's satire is more Juvenalian (sharp and bitter) than Horatian (gentle).
Early in the epistle, which is essentially a dialogue between Pope and Arbuthnot, Pope describes the origins of his affinity for poetry:
Why did I write? what sin to me unknown
Dipp'd me in ink, my parents', or my own?
As yet a child . . . I lisp'd in numbers, for the numbers came.
I left no calling for this idle trade,
No duty broke, no father disobey'd. . . . To...
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