Someone recently broad-shouldered their way into a decent discussion of a poem by David Blair in order to achieve little else than suggest that those present were taking themselves too seriously with all this high=falutin' nonsense. Predictably, he concluded with the stale bromide Alistair MacLeish that a "poem should not mean but be." That, he supposed , would be the end of it, but those who know MacLeish and his Modernist cousins can sniff a misreading when the aroma seeps under the door. It should be noted that what MacLeish intended (or, let us say, meant is that poetry itself ought not mistake itself as an adjunct of philosophy and render what otherwise be formal
arguments in verse form; the modernism he was apart of, along with Pound, Eliot, and especially WC Williams, was to slough off the preceding Romantic tradition , with it's habit of heroically trying to wrestle the existence into order.
The general concern with the early modernist poets was to treat the poem as if were a hard, malleable material and to write poems that , like paintings , sculpture, photography, would get across human perception, with words and phrases that adhered to the cadence of the speaking voice and which used no linguistic buttressing. "The thing itself is it's own adequate symbol"
I believe how Williams put it. This wasn't , though, a proviso against detailed interpretation of poems--Pound, Eliot, and the others obviously wanted their audiences to see the world in new ways, free of the burden of the past. In keeping with their general desire to improve the language and how it can be used, their aim was also to inspire a more vigorous discussion of the work and, in doing so, about the world we live in