How does x understand the impulse that motivated y?

A FRIEND GAVE ME a copy of Alfred Schnitke's Choir Concerto last week. After listening to it I wrote him "Oddly it recalls Feldman, whose music is very different, but gets to the same place." Tim responded

Yes, maybe like you, I am all about "how does a work understand the impulse that motivated Feldman's composing" these days.  I have a new release of and by Boulez and the EC which I think would fit into your listening… Feldman and Cage and Ligeti are pertinent…

This kind of thinking is what I had in mind yesterday.

How does x understand the impulse that motivated y?

The intent is always toward the synoptic, toward a comprehension of where we are (since an understanding of it seems unlikely).

Certain of these thinking creators—these composers, writers, painters, artists—have synoptic views themselves, but use them to push through to new understandings; among them the people I listed yesterday.

To take just one case: John Cage said, somewhere, that while he rejects Beethoven (and, I think, the rest of the 19th century), he attends to Mozart, because there is so much going on at the same time in Mozart. How does Cage understand (and that also means "interpret") the impulse that motivated Mozart?

How did the second half of the 20th century understand the impulse (or impulses) that motivated the first half? (Geert Mak's In Europe is "about" that question, among other things.)

Let's list those visionaries, and gather their work as Silliman suggested, and begin a synoptic critical survey with Tim's question in mind.