What was that battle about, back in St. Petersburg, in Viacheslav Ivanov's "tower", at the turn of the LAST century, between Russian "Symbolists" & "Acmeists"?
& why should this matter to you, bloggiste?
Symbolism was a cultural paradigm, part of the atmosphere, fin-de-siecle. Mallarme one of its chief avatars.
Mallarme took the alienation, the de-centeredness, the Void (drawn in subterranean fashion from Poe) - in itself an inalienable element of human experience (in traditional Christian terms, "fallenness") - and applies it, translates it, into a theory of language. And a script for the social role of Poet.
In this operation, he was percursor of much philosophy, much theory, for the century to follow. Thus the exaltation of Poetry among the philosophers, from Heidegger to Derrida. (Maybe the existentialists, drawing from Kierkegaard, were more realistic about the (in)adequacy of poetry & language as antidote for experiential alienation.)
In Symbolism, the magic of language replaced traditional religion as the skeleton key to the heavenly, otherworldly saferoom.
Acmeism was a struggle against this literary pseudo-religion. Elena Corrigan, in Mandelshtam's Poetics, relates how difficult & longlasting this struggle was for M. in particular. His early poetry was Symbolist in tenor, & suffused with an awareness of the "non-being" of poetic speech, the inherent "displacement" of experience.
The "school", the "theory" of Acmeism was a formulation of literary principles on the level of the essay & the manifesto. One of its basic attitudes was an enmity toward symbolist "stars" & otherworlds. Poetry somehow had to participate in & celebrate the goodness to be found in this world; it was to participate, through "craft", in civilization-building and the continuity of culture.
Such an attitude (stemming from pre-WW I, pre-Revolution Russia) sounds naive in comparison with the subtle obliterations of 20th-cent. post-structuralism & deconstruction, the Mallarmean myths of the empty, de-signified word.
Corrigan describes how Mandelstam's own working theory changed & developed through the 20s & 30s. The notion of literary culture-building molted into a concept of fellowship, "kinship", between reader/writer. Symbolist otherness in poetic speech was absorbed into a larger pattern of "reading" - which begins in catastrophic break or alienation (the text from reality), but metamorphoses into a kind of journey, of kinship & recognition.
It seems to me that underlying these theoretical positions (symbolism, acmeism, affirmation, alienation) are more basic stances or attitudes - psychic responses to positive & negative experience.
Literature can acknowledge, name & identify the terrors of life : it can even (as in the case of Mallarme & symbolism & many of the theoretical discourses that followed) produce a philosophical armature or logic which identifies with, sometimes glorifies in, existential absence, dislocation, meaninglessness.
The anguish of existence is a human predicament, an aspect of experience.
Poe & Whitman might be seen as avatars of these opposing stances : anguish or celebration; denial or affirmation.
But it would be a mistake to channel poetry into a theory of language which sponsors only one or the other stance.
Identity, non-identity. Being, otherness...
Language doesn't merely displace or obliterate or create a phantasm of the thing it represents. The relation is dialectic between word & thing; speech can move toward both denial & affirmation, blindness & recognition. So the theory of poetry based on a language of displacement & non-identity is a partial one, which limits poetry to only one half of the phenomenon.
Every affirmation in words represents a kind of promissory note, a letter of credit - standing for the fact, deed, thing which it affirms. Thus a poetry situated in the language of affirmation is constitutionally modest & humble - it acknowledges its own partiality. It does not replace the flower but depends upon it, stems from it. (Mallarme's recognition of the displacement effect of language also humbles poetry, in another way. It destroys rhetorical bombast. But only so long as it refrains from becoming a technique, a modus operandi, in its own right : a complacent acceptance, a glorification, of alienation.)
Mandelshtam's Acmeism developed not only in conflict with the abstractions of Symbolism, but in conflict with the violence & fraud of the State, and with the constitutional fatalism of Russia. Thus in this context the literary "Word" was pure affirmation - "the Word is bread - it shares the fate of people : suffering" (or something like that). How different from the Mallarmean notion of the Word as purified of worldly corruption! Actually, they share an idealism of poetic speech - but for Mandelshtam this is rooted in "the people" as language-nation, the people as a whole - rather than solely in the poet as scapegoat, (self)sacrifice.
I think you can see in Celan's fascination with Mandelstam a means by which he tried to integrate poetic speech (at the most knowing & sophisticated depth of literary self-alienation) with a kind of silent or unspoken "sense" - of solidarity with the living & the suffering. & to make this fusion a "definition" of poetry.