[Nicolai P. Zwar]

Personally, I just made the analogy of art that can be divided into “blueprint” (play, screenplay, score) and execution (play, movie, performance) to make a specific point; I wouldn’t overinterpret or analyze it.
Obviously, they all differ. What they have in common is that they are performance art with a set of instructions. A play has actors performing written parts guided by a director, a symphony has musicians playing written music guided by a conductor.

West Side Story is not Romeo and Julia, though it’s inspired by it. But it’s got it’s own book… however, we’ve got two West Side Stories on film.