David Hess blogs nimbly among the concepts, & creates some critical synergy out of comments by Ron, Nada, Jack Kimball, et al. He writes:

"O'Hara's poems always seemed very contemplative to me even though they were
full of what you might call 'action'. It strikes me how (taboo word acoming)
accessible they are despite their range of cultural knowledge/materials. Pound
reassured the reader that they needn't know Greek or Italian to understand his
poetry as he himself believed he didn't need to know Chinese to understand its
ideograms. But since he positions himself as a bestower of culture -- culture as a
repository of knowledge that can just be passed around like a hot potato, like
money really -- one must know it.

In O'Hara expressiveness and contemplativeness are not mutually exclusive.
Thinking is not equated with knowing. You do not need to have heard which
symphony he's talking about to "get it." Poets of knowledge, Eliot and Pound, and
poets of being, O'Hara or Oppen or Reznikoff or Celan. I believe the language
poets, to make a sweeping generalization, never knew which kind they wanted to
become. To be systematizers or anti-systematizers -- the dilemma is at the core
of the question of the avant-garde."

Let's take this dichotomy between knowledge/being, system/anti-system, & think about it for a minute. A poem is basically a set of gestures, speech acts, words, united in some kind of aesthetic system (or form of beauty). Because the system is not always obvious to us doesn't mean it isn't there. (sounds like a quote from Zap Comics) But our perception or response to anything is a response to system or organization or pattern.

O'Hara's presentation of fact & knowledge may seem more accessible than Pound's, precisely because he doesn't have Pound's Olympian-didactic angle of approach. But this doesn't make his poetry less of a "system of knowledge" : it's just less overt. Proust has a system : but his work may be the most successful modernist evocation of "being" of all. These aesthetic systems are just different from discursive or philosophical or scientific systems : their consistency is one of style, leading to wholeness or complexity of presentation.

The crack-up & revolutions & wars of the turn of the 20th century brought an end to many a narrative form. This break-up provided an opportunity for poets: modernist & postmodernist technique provided a lever for poetry to challenge the hegemony of prose fiction. & who emerged as the avatar of poetic knowledge? The uber-systematizer : Dante. Dante's "scaffolding" lies behind Pound's grab-bag and behind Eliot's Christian poetics (the poetics of religious transcendence providing another convenient lever of cultural authority against the fiction writers). Both Joyce & Pound balanced Homer against Dante, recapitulating the conceptual movement of the Renaissance in general : all this recapitulation a sign of the end of the age which began with the Renaissance.

With this sketch of literary history, look again at Hess's concluding sentence. Postmodernism is often juxtaposed with modernism as anti-system against system. Both make claims to represent the future (the avant-garde) - the whole spectrum, from Eliot to Dada. But maybe the real issue is, what follows from the scaffoldings erected in the early 20th-century in response to the opportunity offered by chaos (the end of 19th-century/Renaissance/Enlightenment narrative certainties)? because the scaffoldings were only the overt systems. Joyce himself showed this with Finnegans Wake - here he out-systemed his own systems, & showed that chaos & system were the same thing.

The power of aesthetic effect of any particular work of art is limited & variable - that is, it depends on the power of apprehension by the audience, as well as on the author's own discernment & ability to build complexity into those same limitations (the "implicate universe" of David Bohm). Thus it may take decades, or centuries even, for the implications of an aesthetic system to work their effects, their magic. (As an example, Mandelstam emphasized the future-oriented quality of Dante's poem.) These centuries may develop new constellations of perception & value, so that, for example, O'Hara's cute notion of "Personism" may not be so simple after all : it may be appreciated as an element of an aesthetic system, a worldview, a metaform.

The New doesn't go away : only time-bound versions of the new, scaffoldings & fashionable systematizations, get old. The perpetual death of the "avant-garde" is simply the continual obsolescence of literary fashions which were flimsy surface phenomena to begin with. There is no simple dichotomy of knowledge & being : only genuine, original aesthetic systems (of perception, of expression) vs. hack work & rhetorical sleights-of-hand.

Perhaps the "new" system of critical valuation to be applied to the "post-avant" generation will depend from somewhere between Bakhtin & Mandelstam. It will apprehend the dialogic appropriation of prior poetries, the overlay of thought, feeling, and expression borrowed from previous poets, for the aesthetic necessities of a new person & a new time. It will respond to the individuality of this new voice, rather than hurry to place it within some group regime or political stance. It will measure the range, originality, pitch, loudness, & specific gravity of the individual voice on its own terms, before applying simplistic comparisons.