I believe he's some sort of Delta NF and I hazard INFj > ENFp. To be honest, his poetry cuts along a similar curve as my own (back when I used to write). There seems to be a wide-ranging attitude behind it all that's preoccupied far more with what could be in the world and the people in it. His work also exudes Fi, with focuses on knowledge as a tool for growth, rather than a treasure to be gathered for its own sake.