One case included in the book is a poem called "The Connecticut Wit," written to convince the Connecticut Constitutional Convention to pass the Constitution.
"It isn't often that you find a piece of literature that diversely affected the American political scene," Engell says, adding that the poem was widely quoted and cited during debates over the Constitution.
He says the book shows how literature can be "an instrument for people in other professions."
"I don't think we've done a particularly good job of teaching that in the United States in the past 50 to 75 years," he says.
Now living in Acton, Mass. with his wife of 14 years and their son, Engell's time is under constant demand, which he says makes it difficult for him to focus.
All the same, it's the enjoyability of this productive, albeit hectic, pace that Engell says keeps him at Harvard.
"It is like having 150 cable stations," he says. "The only problem is that all of the stations are good."