>>24795356
And I agree with the definition, with scale additionally denoting the time scale. Divine Comedy covers everything from Biblical time and the antiquity to Dante's future through prophecy. Between all the mythological references, historical figures from all time periods, Italian politics, symbolism, the litany of saints in Paradiso, medieval cosmology, and theological discussion the Divine Comedy is a very dense poem that you'd be hard-pressed to tackle without annotations due to its sheer density of information.
For me the scope is what the book covers, or how Universal it is to the Human Condition. You have books that are a snapshot of a specific time period, books that cover ideology vast historical forces controlling the human lives, and at the very top there are theological and philosophical books that deal with the human soul directly.
Faust part 2 transforms part 1's deeply personal tragedy and makes it universal. Between Faust dealing with kings, wars, and giant industrial projects and the classical walpurgisnacht, culminating in the eternal-feminine, there are few books with scope as broad as that of Faust. And anyone that made it through the classical walpurgisnacht will tell you that its scale is also massive.
I choose to put zero weight on the characters and the actual plot when talking about scope and scale. Just the pure erudition, the information density, as well as the closeness of themes to philosophy and theology.