Frost is saying a poem must be about ideas, otherwise it's just bric-a-brac. Wallace (no slouch as an acclaimed poet) disagrees because for him a poem's "ideas" are not important. "A poem should not mean, but be."

In a similar vein Wittgenstein mused:

"An observation in a poem is overstated if the intellectual points are nakedly exposed, not clothed from the heart.", or in the case of Frost perhaps it's from mind that they must be veiled to allow for a personal discovery or interior experience. Doesn’t written language enter the brain along silent corridors and from these into the mind and then into the blood? (I am thinking of eyes and in the case of braille: fingers) Certainly this is not the same pathway that spoken language; the language of poetry with its vital relationship to sound and music traveled in the past.

Perhaps this accounts for part of the reason why we’ve lost some of the intimate and vital connection that classical Greek audiences are said to have had with poetry and poets.

However, I think Zeus Boy has a point that doesn't necessarily contradict either of these views. I find Wittgenstein's writing to be highly concentrated and "poetic". He wrote somewhere that: “Philosophy ought really to be written only as a poetic composition.” And he said of his philosophy that, “Each of the sentences I write is trying to say the whole thing, i.e. the same thing over and over again; it is as though they were all simply views of one object seen from different angles.”

The idea that ideas are necessarily unnatural and foreign to being is implicit in Wallace's viewpoint. Wittgenstein makes some observations and statements about Shakespeare and his writing that have probably alienated many Shakespeare admirers but seem to coincide in the extreme with Wallace's view. Here is a sampling:

"I do not believe that Shakespeare can be set alongside any other poet. Was he perhaps a creator of language rather than a poet?

"I am deeply suspicious of most of Shakespeare's admirers. The misfortune is, I believe, that he stands by himself, at least in the culture of the west, so that one can only place him by placing him wrongly."

"It is not as though Shakespeare portrayed human types well and were in that respect true to life. He is not true to life. But he has such a supple hand and his brush strokes are so individual, that each one of his characters looks significant.."

"Beethoven's great heart" - "nobody could speak of Shakespeare's great heart. The supple hand that created new natural linguistic forms would seem to me nearer the mark."

A poet cannot really say of himself "I sing as the birds sing"- but perhaps Shakespeare could have said this of himself.

"I do not think that Shakespeare would have been able to reflect on the 'lot of the poet'. Nor could he regard himself as a prophet or as a teacher of mankind. People stare at him in wonderment, almost as at a spectacular natural phenomenon. They do not have the feeling that this brings them into contact with a great human being. Rather with a phenomenon.

"His pieces give me an impression as of enormous sketches rather than of paintings; as though they had been dashed off by someone who can permit himself anything, so to speak. And I understand how someone can admire that and call it supreme art, but I don't like it. - So if someone stands in front of these pieces speechless, I can understand him; but anyone who admires them as one admires, say, Beethoven, seems to me to misunderstand Shakespeare."