Lately, I have been thinking a lot about this aphorism . It seems to have as many originators as it does permutations. The gist of it is, “good writers borrow; great writers steal.”
I first heard it from a mid-list science fiction writer  who claimed he had stolen it from the guy  who had stolen it from the guy who had stolen it from T.S. Eliot . Eliot stole it from Oscar Wilde , but from whom Wilde had stolen it is anybody’s guess. He, undoubtedly said it more pithily than his predecessor. To show you how these things warp through time (and perhaps how far the literary discourse has devolved)--according to our space-age, algorithmic oracle, Google , the current originator of the saying is one Aaron Sorkin , who may be a heckuva human being, and a man of immense accomplishments, but I, for one, am not sure he has the gravitas to be the bearer, even temporarily, of such awesome power. It's like having Magilla Gorilla  with his finger on The Button .
The point I'm trying to make here (I think) is that influence is inescapable. Poets can't help stealing from all those who came before. Humans, as a species, are born kleptomaniacs . Culture is an endless process of appropriation. Art is an act of theft, whether it be stealing the appearance of two figs and a wine bottle and remaking it as an oil-on-canvas still life, or plucking from the communal store of words to make a sestina . The fact is, we could play Six Degrees  of Francis Bacon  linking any given poet back to the once-reputed author of the works of William Shakespeare  (himself an accomplished thief). Even if a poet has never read the King James Bible , say, he or she has read many poets who have, and whose work is deeply informed by its rhythms and motifs. It is no accident that influence and influenza  come from the same root. Certain poets throughout the ages seem to have been carriers of their own particular and virulent contagion.
Ezra Pound 's smudgy fingerprints are all over Eliot's The Waste Land , but the effects of his strain of literary modernism can be seen in the work of (the unjustly underrated) H.D. , Hemingway  and many others .
The University of Houston's own Tony Hoagland  sees the poet Dean Young  as a veritable Typhoid Mary . (Read the full text of Hoagland's "The Dean Young Effect" from American Poetry Review, Jul/Aug 2009, Vol. 38 Issue 4 by accessing Harris County Public Library's databases: Masterfile Premier .
Finally, for an interesting discussion of influence between mentors and proteges, read 12 x 12: Conversations in 21st-Century Poetry and Poetics .
Photo Credit: Glad Day for Surfin,' after William "Hodad" Blake by Mike Licht , NotionsCapital.com