The reason I am posting about Burnt Norton is that I've got it nagging at me and I have to write it out, to clear it out of my head somehow.
(I'm not going to keep saying 'it seems to me' and 'I think that', but take it for granted that anything I might say about the poem is just my opinion.)
The first few lines of Burnt Norton were a blunt logical setting out of an argument: the past and future give meaning to the present but they don't exist. If we believe in free will then there is another kind of even more non-existent past - the one that could have happened but didn't.
The present is the pivot or hinge between the past and future. Similarly this verse is pivoted. I am reminded of the double-spiral motif that runs through Le Guin's Always Coming Home (and The left hand of darkness) and of course the Yin/Yang symbol.
Following the sparse logical verbal wing, there will be a soft intuitive wing which is all imagery. Between the two is the pivot which goes like this:
My words echoThus, in your mind.But to what purposeDisturbing the dust on a bowl of rose-leaves
I do not know.
He's concluding the logical section, saying 'This poem is an example of what I'm talking about'. To Eliot his readers are all in the non-existent future, and to me he is in the obliterated past. All that remains of his act of writing is the echo in my mind, this moment, as I read the poem. And he has no control over that. This is the tough-minded tying-up of the first wing.
And then the next line initiates the soft intuitive wing. The Rose is the image of goodness and transcendence (and a pun on rising up) and the leaves are what is left behind, another pun, and the dusty old rose leaves are the dry left overs of a lost visit to the garden, a metaphor for the poem itself. So the words and the image echo each other.
He concludes the pivot with 'I don't know' and that leads into the non-logical wing, which is about him going back and trying to put right what once went wrong, by revisiting the door into the rose garden, and this time going through it.
egretplume said that there was a hint of the parallel worlds theory, and I think that's true, and in the next wing Eliot goes back up what Terry Pratchett would call the trousers of time, and takes the other leg...