I had not thought about the persona being blind, though being non-literate had been a thought. It's the line about writing it down so that somebody can read it to him that does it. For me otherwise, it's about a darkness of the soul, a state of near madness 'stop driving me mad', and the need for some other to provide support, almost religious connotations and certainly a moral element 'tell me when I'm lying.' Poignantly relevant to Peter Green's biography (his version is the one I know) in places. 'Odd' is one way of putting it, 'intriguing' another perhaps.