Ars Poetica

Archibald MacLeish's short Ars Poetica ends with the rather famous following two lines:

A poem should not mean
But be.

These lines are quoted fairly frequently. For example, they were the basis for an answer on Jeopardy last night. I confess that I don't understand what they mean. Based on the lines themselves, I suppose that's a silly question, since I suppose they just 'are'. Perhaps the point is to make interpretation seem ridiculous, but leaving that aside--what, really, does it mean (gasp) for a poem not to 'mean/ But be'?

The text can be found here or here. More interesting is an image of the original manuscript here.

UPDATE: To put it a little more clearly: a believer in MacLeish's axiom couldn't answer my question on grounds of principle, for to do so would be a violation of the axiom. It seems to be intended as a metapoetic comment on poetry as such, but, given that it comes in a poem, as soon as one extracts the comment--the 'meaning' of part of the poem--to apply it to how we read poems in general, he does violence to the principle that a poem does not 'mean/ But [is]'. Dennis' idea of paradox is a good way of looking at it. For the more cynical, 'nonsense' is another.