[An original function of language] was to exclude from attention what was unimportant to the task at hand, thereby providing an ordering of the experience of the world. That exclusion, which characterizes rationality and discursiveness, is also useful to poetry, because it is in the balance between order and inclusion that poems are made. As Stevens said, "The poem must resist the intelligence almost successfully. The "blessed rage for order" must win in the end because it is that which allows us to survive. However, if the battle against it is not a raging battle, the poem will seem to have excluded too much.
A Difficult Grace: On Poets, Poetry, and Writing, Michael Ryan