What do you think it means that we should be able to touch a poem, but not hear it?
A poem should be wordless
As the flight of birds. (7-8)
We can't hear the flight of birds (unless it's those honkin' geese), but the beauty of them flying is what's really important. Likewise, the beauty and feeling of a poem should be palpable, but we shouldn't have to hear a bunch of noise to go along with it.
A poem should be equal to:
Not true. (17-18)
A poem shouldn't communicate "truths" to us. It should equal something in the sense of a "truth" being felt rather than told. So a poem shouldn't seek to define anything for us but should rather inspire us to think and feel freely.