Perhaps That's What I Feel, An Outside

Perhaps That's What I Feel, An Outside And An Inside And Me In The Middle, Perhaps That's What I Am, The Thing That Divides The World In Two, On The One Side The Outside, On The Other The Inside, That Can Be As Thin As Foil, I'm Neither One Side Nor The Other, I'm In The Middle, I'm The Partition, I've Two Surfaces And No Thickness, Perhaps That's What I Feel, Myself Vibrating, I'm The Tympanum, On The One Hand The Mind, On The Other The World, I Don't Belong To Either.