Paul Muldoon on Seamus Heaney in The Daily Beast:
If, as Eliot suggested, the mark of a great poet is that she or he will develop the milieu in which her or his work is seen to matter, then Heaney certainly had an educator’s gift for drawing out his readers and transporting them to places where they simply wouldn’t have expected to be. The truth is that he developed into a much more complex poet than anyone might have imagined, one who was increasingly recognized as having insights into not only plows, horses, and frogs, but international politics, human rights, and the attack on the World Trade Center. He was the only poet I can think of who was recognized worldwide as having moral as well as literary authority and, as such, may be the last major poet to even entertain such a possibility.